arducopter.py

#!/usr/bin/env python

# Fly ArduCopter in SITL
from __future__ import print_function
import math
import os
import shutil
import time
import traceback

import pexpect
from pymavlink import mavutil
from pymavlink import mavextra

from pysim import util, rotmat

from common import AutoTest
from common import NotAchievedException, AutoTestTimeoutException, PreconditionFailedException

# get location of scripts
testdir = os.path.dirname(os.path.realpath(__file__))
SITL_START_LOCATION = mavutil.location(-35.362938, 149.165085, 584, 270)
SITL_START_LOCATION_AVC = mavutil.location(40.072842, -105.230575, 1586, 0)


# Flight mode switch positions are set-up in arducopter.param to be
#   switch 1 = Circle
#   switch 2 = Land
#   switch 3 = RTL
#   switch 4 = Auto
#   switch 5 = Loiter
#   switch 6 = Stabilize


class AutoTestCopter(AutoTest):

    def log_name(self):
        return "ArduCopter"

    def test_filepath(self):
         return os.path.realpath(__file__)

    def sitl_start_location(self):
        return SITL_START_LOCATION

    def mavproxy_options(self):
        ret = super(AutoTestCopter, self).mavproxy_options()
        if self.frame != 'heli':
            ret.append('--quadcopter')
        return ret

    def sitl_streamrate(self):
        return 5

    def vehicleinfo_key(self):
        return 'ArduCopter'

    def default_frame(self):
        return "+"

    def uses_vicon(self):
        return True

    def close(self):
        super(AutoTestCopter, self).close()

        # [2014/05/07] FC Because I'm doing a cross machine build
        # (source is on host, build is on guest VM) I cannot hard link
        # This flag tells me that I need to copy the data out
        if self.copy_tlog:
            shutil.copy(self.logfile, self.buildlog)

    def is_copter(self):
        return True

    def get_stick_arming_channel(self):
        return int(self.get_parameter("RCMAP_YAW"))

    def get_disarm_delay(self):
        return int(self.get_parameter("DISARM_DELAY"))

    def set_autodisarm_delay(self, delay):
        self.set_parameter("DISARM_DELAY", delay)

    def user_takeoff(self, alt_min=30):
        '''takeoff using mavlink takeoff command'''
        self.run_cmd(mavutil.mavlink.MAV_CMD_NAV_TAKEOFF,
                     0, # param1
                     0, # param2
                     0, # param3
                     0, # param4
                     0, # param5
                     0, # param6
                     alt_min # param7
                     )
        self.progress("Ran command")
        self.wait_for_alt(alt_min)

    def takeoff(self,
                alt_min=30,
                takeoff_throttle=1700,
                require_absolute=True,
                mode="STABILIZE",
                timeout=30):
        """Takeoff get to 30m altitude."""
        self.progress("TAKEOFF")
        self.change_mode(mode)
        if not self.armed():
            self.wait_ready_to_arm(require_absolute=require_absolute)
            self.zero_throttle()
            self.arm_vehicle()
        self.set_rc(3, takeoff_throttle)
        self.wait_for_alt(alt_min=alt_min, timeout=timeout)
        self.hover()
        self.progress("TAKEOFF COMPLETE")

    def wait_for_alt(self, alt_min=30, timeout=30):
        """Wait for altitude to be reached."""
        m = self.mav.recv_match(type='GLOBAL_POSITION_INT', blocking=True)
        alt = m.relative_alt / 1000.0 # mm -> m
        if alt < alt_min:
            self.wait_altitude(alt_min - 1,
                               (alt_min + 5),
                               relative=True,
                               timeout=timeout)

    def land_and_disarm(self, timeout=60):
        """Land the quad."""
        self.progress("STARTING LANDING")
        self.change_mode("LAND")
        self.wait_altitude(-5, 1, relative=True, timeout=timeout)
        self.progress("LANDING: ok!")
        self.mav.motors_disarmed_wait()

    def hover(self, hover_throttle=1500):
        self.set_rc(3, hover_throttle)

    # loiter - fly south west, then loiter within 5m position and altitude
    def loiter(self, holdtime=10, maxaltchange=5, maxdistchange=5):
        """Hold loiter position."""
        self.takeoff(10, mode="LOITER")

        # first aim south east
        self.progress("turn south east")
        self.set_rc(4, 1580)
        self.wait_heading(170)
        self.set_rc(4, 1500)

        # fly south east 50m
        self.set_rc(2, 1100)
        self.wait_distance(50)
        self.set_rc(2, 1500)

        # wait for copter to slow moving
        self.wait_groundspeed(0, 2)

        m = self.mav.recv_match(type='VFR_HUD', blocking=True)
        start_altitude = m.alt
        start = self.mav.location()
        tstart = self.get_sim_time()
        self.progress("Holding loiter at %u meters for %u seconds" %
                      (start_altitude, holdtime))
        while self.get_sim_time_cached() < tstart + holdtime:
            m = self.mav.recv_match(type='VFR_HUD', blocking=True)
            pos = self.mav.location()
            delta = self.get_distance(start, pos)
            alt_delta = math.fabs(m.alt - start_altitude)
            self.progress("Loiter Dist: %.2fm, alt:%u" % (delta, m.alt))
            if alt_delta > maxaltchange:
                raise NotAchievedException(
                    "Loiter alt shifted %u meters (> limit %u)" %
                    (alt_delta, maxaltchange))
            if delta > maxdistchange:
                raise NotAchievedException(
                    "Loiter shifted %u meters (> limit of %u)" %
                    (delta, maxdistchange))
        self.progress("Loiter OK for %u seconds" % holdtime)

        self.progress("Climb to 30m")
        self.change_alt(30)

        self.progress("Descend to 20m")
        self.change_alt(20)

        self.do_RTL()

    def watch_altitude_maintained(self, min_alt, max_alt, timeout=10):
        '''watch alt, relative alt must remain between min_alt and max_alt'''
        tstart = self.get_sim_time_cached()
        while True:
            if self.get_sim_time_cached() - tstart > timeout:
                return
            m = self.mav.recv_match(type='VFR_HUD', blocking=True)
            if m.alt <= min_alt:
                raise NotAchievedException("Altitude not maintained: want >%f got=%f" % (min_alt, m.alt))

    def test_mode_ALT_HOLD(self):
        self.takeoff(10, mode="ALT_HOLD")
        self.watch_altitude_maintained(9, 11, timeout=5)
        # feed in full elevator and aileron input and make sure we
        # retain altitude:
        self.set_rc(1, 1000)
        self.set_rc(2, 1000)
        self.watch_altitude_maintained(9, 11, timeout=5)
        self.set_rc(1, 1500)
        self.set_rc(2, 1500)
        self.do_RTL()

    def change_alt(self, alt_min, climb_throttle=1920, descend_throttle=1080):
        """Change altitude."""
        m = self.mav.recv_match(type='GLOBAL_POSITION_INT', blocking=True)
        alt = m.relative_alt / 1000.0 # mm -> m
        if alt < alt_min:
            self.progress("Rise to alt:%u from %u" % (alt_min, alt))
            self.set_rc(3, climb_throttle)
            self.wait_altitude(alt_min, (alt_min + 5), relative=True)
        else:
            self.progress("Lower to alt:%u from %u" % (alt_min, alt))
            self.set_rc(3, descend_throttle)
            self.wait_altitude((alt_min - 5), alt_min, relative=True)
        self.hover()

    #################################################
    #   TESTS FLY
    #################################################

    # fly a square in alt_hold mode
    def fly_square(self, side=50, timeout=300):

        self.clear_mission()

        self.takeoff(10)

        """Fly a square, flying N then E ."""
        tstart = self.get_sim_time()

        # ensure all sticks in the middle
        self.set_rc(1, 1500)
        self.set_rc(2, 1500)
        self.set_rc(3, 1500)
        self.set_rc(4, 1500)

        # switch to loiter mode temporarily to stop us from rising
        self.change_mode('LOITER')

        # first aim north
        self.progress("turn right towards north")
        self.set_rc(4, 1580)
        self.wait_heading(10)
        self.set_rc(4, 1500)

        # save bottom left corner of box as waypoint
        self.progress("Save WP 1 & 2")
        self.save_wp()

        # switch back to stabilize mode
        self.change_mode('STABILIZE')

        # increase throttle a bit because we're about to pitch:
        self.set_rc(3, 1525)

        # pitch forward to fly north
        self.progress("Going north %u meters" % side)
        self.set_rc(2, 1300)
        self.wait_distance(side)
        self.set_rc(2, 1500)

        # save top left corner of square as waypoint
        self.progress("Save WP 3")
        self.save_wp()

        # roll right to fly east
        self.progress("Going east %u meters" % side)
        self.set_rc(1, 1700)
        self.wait_distance(side)
        self.set_rc(1, 1500)

        # save top right corner of square as waypoint
        self.progress("Save WP 4")
        self.save_wp()

        # pitch back to fly south
        self.progress("Going south %u meters" % side)
        self.set_rc(2, 1700)
        self.wait_distance(side)
        self.set_rc(2, 1500)

        # save bottom right corner of square as waypoint
        self.progress("Save WP 5")
        self.save_wp()

        # roll left to fly west
        self.progress("Going west %u meters" % side)
        self.set_rc(1, 1300)
        self.wait_distance(side)
        self.set_rc(1, 1500)

        # save bottom left corner of square (should be near home) as waypoint
        self.progress("Save WP 6")
        self.save_wp()

        # reduce throttle again
        self.set_rc(3, 1500)

        # descend to 10m
        self.progress("Descend to 10m in Loiter")
        self.mavproxy.send('switch 5\n')  # loiter mode
        self.wait_mode('LOITER')
        self.set_rc(3, 1300)
        time_left = timeout - (self.get_sim_time() - tstart)
        self.progress("timeleft = %u" % time_left)
        if time_left < 20:
            time_left = 20
        self.wait_altitude(-10, 10, time_left, relative=True)
        self.set_rc(3, 1500)
        self.save_wp()

        # save the stored mission to file
        num_wp = self.save_mission_to_file(os.path.join(testdir,
                                                        "ch7_mission.txt"))
        if not num_wp:
            self.fail_list.append("save_mission_to_file")
            self.progress("save_mission_to_file failed")

        self.progress("test: Fly a mission from 1 to %u" % num_wp)
        self.mavproxy.send('wp set 1\n')
        self.change_mode('AUTO')
        self.wait_waypoint(0, num_wp-1, timeout=500)
        self.progress("test: MISSION COMPLETE: passed!")
        self.change_mode('LAND')
        self.mav.motors_disarmed_wait()

    # enter RTL mode and wait for the vehicle to disarm
    def do_RTL(self, timeout=250):
        """Return, land."""
        self.change_mode("RTL")
        self.set_rc(3, 1500)
        tstart = self.get_sim_time()
        while self.get_sim_time_cached() < tstart + timeout:
            m = self.mav.recv_match(type='GLOBAL_POSITION_INT', blocking=True)
            alt = m.relative_alt / 1000.0 # mm -> m
            home_distance = self.distance_to_home(use_cached_home=True)
            home = ""
            if alt <= 1 and home_distance < 10:
                home = "HOME"
            self.progress("Alt: %.02f  HomeDist: %.02f %s" %
                          (alt, home_distance, home))
            # our post-condition is that we are disarmed:
            if not self.armed():
                if home == "":
                    raise NotAchievedException("Did not get home")
                # success!
                return
        raise AutoTestTimeoutException("Did not get home and disarm")

    def fly_loiter_to_alt(self):
        """loiter to alt"""

        self.context_push()

        ex = None
        try:

            self.set_parameter("PLND_ENABLED", 1)
            self.fetch_parameters()
            self.set_parameter("PLND_TYPE", 4)

            self.set_parameter("RNGFND1_TYPE", 1)
            self.set_parameter("RNGFND1_MIN_CM", 0)
            self.set_parameter("RNGFND1_MAX_CM", 4000)
            self.set_parameter("RNGFND1_PIN", 0)
            self.set_parameter("RNGFND1_SCALING", 12.12)

            self.reboot_sitl()

            self.load_mission("copter_loiter_to_alt.txt")

            self.mavproxy.send('switch 5\n')
            self.wait_mode('LOITER')

            self.wait_ready_to_arm()

            self.arm_vehicle()

            self.mavproxy.send('mode auto\n')
            self.wait_mode('AUTO')

            self.set_rc(3, 1550)

            self.wait_current_waypoint(2)

            self.set_rc(3, 1500)

            self.mav.motors_disarmed_wait()
        except Exception as e:
            ex = e

        self.context_pop()
        self.reboot_sitl()

        if ex is not None:
            raise ex

    def fly_throttle_failsafe(self, side=60, timeout=180):
        """Fly east, Failsafe, return, land."""

        self.takeoff(10)

        # switch to loiter mode temporarily to stop us from rising
        self.change_mode('LOITER')

        # first aim east
        self.progress("turn east")
        self.set_rc(4, 1580)
        self.wait_heading(135)
        self.set_rc(4, 1500)

        # raise throttle slightly to avoid hitting the ground
        pos = self.mav.location(relative_alt=True)
        if pos.alt > 25:
            self.set_rc(3, 1300)
            self.wait_altitude(20, 25, relative=True)
        if pos.alt < 20:
            self.set_rc(3, 1800)
            self.wait_altitude(20, 25, relative=True)
        self.hover()

        self.change_mode("STABILIZE")

        self.hover()

        # fly east 60 meters
        self.progress("# Going forward %u meters" % side)
        self.set_rc(2, 1350)
        self.wait_distance(side, 5, 60)
        self.set_rc(2, 1500)

        # pull throttle low
        self.progress("# Enter Failsafe by setting very low throttle")
        self.set_rc(3, 900)

        tstart = self.get_sim_time()
        homeloc = self.poll_home_position()
        home = mavutil.location(homeloc.latitude/1e7,
                                homeloc.longitude/1e7,
                                homeloc.altitude/1e3,
                                0)
        while self.get_sim_time_cached() < tstart + timeout:
            m = self.mav.recv_match(type='GLOBAL_POSITION_INT', blocking=True)
            alt = m.relative_alt / 1000.0 # mm -> m
            pos = self.mav.location()
            home_distance = self.get_distance(home, pos )
            self.progress("Alt: %.02f  HomeDist: %.0f" % (alt, home_distance))
            # check if we've reached home
            if alt <= 1 and home_distance < 10:
                # reduce throttle
                self.set_rc(3, 1100)
                # switch back to stabilize
                self.change_mode("LAND")
                self.progress("Waiting for disarm")
                self.mav.motors_disarmed_wait()
                self.progress("Reached failsafe home OK")
                self.change_mode('STABILIZE')
                self.zero_throttle()
                return

        self.reboot_sitl()

        raise AutoTestTimeoutException(
            ("Failed to land and disarm on failsafe RTL - "
             "timed out after %u seconds" % timeout))

    def fly_battery_failsafe(self, timeout=300):
        self.takeoff(10, mode='LOITER')

        # enable battery failsafe
        self.set_parameter('BATT_FS_LOW_ACT', 1)

        # trigger low voltage
        self.set_parameter('SIM_BATT_VOLTAGE', 10)

        # wait for LAND mode. If unsuccessful an exception will be raised
        self.wait_mode('LAND', timeout=timeout)

        self.progress("Successfully entered LAND after battery failsafe")
        self.mav.motors_disarmed_wait()
        self.reboot_sitl()

    # fly_stability_patch - fly south, then hold loiter within 5m
    # position and altitude and reduce 1 motor to 60% efficiency
    def fly_stability_patch(self,
                            holdtime=30,
                            maxaltchange=5,
                            maxdistchange=10):

        self.takeoff(10, mode="LOITER")

        # first south
        self.progress("turn south")
        self.set_rc(4, 1580)
        self.wait_heading(180)
        self.set_rc(4, 1500)

        # fly west 80m
        self.set_rc(2, 1100)
        self.wait_distance(80)
        self.set_rc(2, 1500)

        # wait for copter to slow moving
        self.wait_groundspeed(0, 2)

        m = self.mav.recv_match(type='VFR_HUD', blocking=True)
        start_altitude = m.alt
        start = self.mav.location()
        tstart = self.get_sim_time()
        self.progress("Holding loiter at %u meters for %u seconds" %
                      (start_altitude, holdtime))

        # cut motor 1 to 55% efficiency
        self.progress("Cutting motor 1 to 60% efficiency")
        self.set_parameter("SIM_ENGINE_MUL", 0.60)

        while self.get_sim_time_cached() < tstart + holdtime:
            m = self.mav.recv_match(type='VFR_HUD', blocking=True)
            pos = self.mav.location()
            delta = self.get_distance(start, pos)
            alt_delta = math.fabs(m.alt - start_altitude)
            self.progress("Loiter Dist: %.2fm, alt:%u" % (delta, m.alt))
            if alt_delta > maxaltchange:
                raise NotAchievedException(
                    "Loiter alt shifted %u meters (> limit %u)" %
                    (alt_delta, maxaltchange))
            if delta > maxdistchange:
                raise NotAchievedException(
                    ("Loiter shifted %u meters (> limit of %u)" %
                     (delta, maxdistchange)))

        # restore motor 1 to 100% efficiency
        self.set_parameter("SIM_ENGINE_MUL", 1.0)

        self.progress("Stability patch and Loiter OK for %us" % holdtime)

        self.progress("RTL after stab patch")
        self.do_RTL()

    def debug_arming_issue(self):
        while True:
            self.send_mavlink_arm_command()
            m = self.mav.recv_match(blocking=True, timeout=1)
            if m is None:
                continue
            if m.get_type() in ["STATUSTEXT", "COMMAND_ACK"]:
                print("Got: %s" % str(m))
            if self.mav.motors_armed():
                self.progress("Armed")
                return

    # fly_fence_test - fly east until you hit the horizontal circular fence
    def fly_fence_test(self, timeout=180):
        # enable fence, disable avoidance
        self.set_parameter("FENCE_ENABLE", 1)
        self.set_parameter("AVOID_ENABLE", 0)

        self.change_mode("LOITER")
        self.wait_ready_to_arm()

        # fence requires home to be set:
        m = self.poll_home_position()
        if m is None:
            raise NotAchievedException("Did not receive HOME_POSITION")
        self.progress("home: %s" % str(m))

        self.start_subtest("ensure we can't arm if ouside fence")
        fence = os.path.join(self.mission_directory(),
                             "fence-in-middle-of-nowhere.txt")
        self.mavproxy.send('fence load %s\n' % fence)
        self.mavproxy.expect("Loaded 6 geo-fence")
        self.delay_sim_time(5) # let fence check run so it loads-from-eeprom
        seen_statustext = False
        seen_command_ack = False

        tstart = self.get_sim_time_cached()
        while True:
            self.send_mavlink_arm_command()
            if seen_command_ack and seen_statustext:
                break
            if self.get_sim_time_cached() - tstart > 5:
                raise NotAchievedException("Did not see failure-to-arm messages (statustext=%s command_ack=%s" % (seen_statustext, seen_command_ack))
            m = self.mav.recv_match(blocking=True, timeout=1)
            if m is None:
                continue
            if m.get_type() == "STATUSTEXT":
                if "vehicle outside fence" in m.text:
                    self.progress("Got: %s" % str(m))
                    seen_statustext = True
                elif "PreArm" in m.text:
                    self.progress("Got: %s" % str(m))
                    raise NotAchievedException("Unexpected prearm failure (%s)" % m.text)

            if m.get_type() == "COMMAND_ACK":
                print("Got: %s" % str(m))
                if m.command == mavutil.mavlink.MAV_CMD_COMPONENT_ARM_DISARM:
                    if m.result != 4:
                        raise NotAchievedException("command-ack says we didn't fail to arm")
                    self.progress("Got: %s" % str(m))
                    seen_command_ack = True
            if self.mav.motors_armed():
                raise NotAchievedException("Armed when we shouldn't have")

        self.progress("Failed to arm outside fence (good!)")
        self.drain_mav()
        self.mavproxy.send('fence clear\n')
        self.delay_sim_time(2)
        self.mavproxy.send('fence list\n')
        self.mavproxy.expect("No geo-fence points")

        self.start_subtest("Check breach-fence behaviour")
        self.set_parameter("FENCE_TYPE", 2)
        self.takeoff(10, mode="LOITER")

        # first east
        self.progress("turn east")
        self.set_rc(4, 1580)
        self.wait_heading(160)
        self.set_rc(4, 1500)

        fence_radius = self.get_parameter("FENCE_RADIUS")

        self.progress("flying forward (east) until we hit fence")
        pitching_forward = True
        self.set_rc(2, 1100)

        self.progress("Waiting for fence breach")
        tstart = self.get_sim_time()
        while not self.mode_is("RTL"):
            if self.get_sim_time_cached() - tstart > 30:
                self.NotAchievedException("Did not breach fence")

            m = self.mav.recv_match(type='GLOBAL_POSITION_INT', blocking=True)
            alt = m.relative_alt / 1000.0 # mm -> m
            home_distance = self.distance_to_home(use_cached_home=True)
            self.progress("Alt: %.02f  HomeDistance: %.02f (fence radius=%f)" %
                          (alt, home_distance, fence_radius))

        self.progress("Waiting until we get home and disarm")
        tstart = self.get_sim_time()
        while self.get_sim_time_cached() < tstart + timeout:
            m = self.mav.recv_match(type='GLOBAL_POSITION_INT', blocking=True)
            alt = m.relative_alt / 1000.0 # mm -> m
            home_distance = self.distance_to_home(use_cached_home=True)
            self.progress("Alt: %.02f  HomeDistance: %.02f" %
                          (alt, home_distance))
            # recenter pitch sticks once we're home so we don't fly off again
            if pitching_forward and home_distance < 50:
                pitching_forward = False
                self.set_rc(2, 1475)
                # disable fence
                self.set_parameter("FENCE_ENABLE", 0)
            if (alt <= 1 and home_distance < 10) or (not self.armed() and home_distance < 10):
                # reduce throttle
                self.zero_throttle()
                self.change_mode("LAND")
                self.progress("Waiting for disarm")
                self.mav.motors_disarmed_wait()
                self.progress("Reached home OK")
                self.zero_throttle()
                return

        # give we're testing RTL, doing one here probably doesn't make sense
        home_distance = self.distance_to_home(use_cached_home=True)
        raise AutoTestTimeoutException(
            "Fence test failed to reach home (%fm distance) - "
            "timed out after %u seconds" % (home_distance, timeout,))

    # fly_alt_fence_test - fly up until you hit the fence
    def fly_alt_max_fence_test(self):
        self.takeoff(10, mode="LOITER")
        """Hold loiter position."""
        self.mavproxy.send('switch 5\n')  # loiter mode
        self.wait_mode('LOITER')

        # enable fence, disable avoidance
        self.set_parameter("FENCE_ENABLE", 1)
        self.set_parameter("AVOID_ENABLE", 0)
        self.set_parameter("FENCE_TYPE", 1)

        self.change_alt(10)

        # first east
        self.progress("turn east")
        self.set_rc(4, 1580)
        self.wait_heading(160)
        self.set_rc(4, 1500)

        # fly forward (east) at least 20m
        self.set_rc(2, 1100)
        self.wait_distance(20)

        # stop flying forward and start flying up:
        self.set_rc(2, 1500)
        self.set_rc(3, 1800)

        # wait for fence to trigger
        self.wait_mode('RTL', timeout=120)

        self.progress("Waiting for disarm")
        self.mav.motors_disarmed_wait()

        self.zero_throttle()

    def fly_gps_glitch_loiter_test(self, timeout=30, max_distance=20):
        """fly_gps_glitch_loiter_test. Fly south east in loiter and test
        reaction to gps glitch."""
        self.takeoff(10, mode="LOITER")

        # turn on simulator display of gps and actual position
        if self.use_map:
            self.show_gps_and_sim_positions(True)

        # set-up gps glitch array
        glitch_lat = [0.0002996,
                      0.0006958,
                      0.0009431,
                      0.0009991,
                      0.0009444,
                      0.0007716,
                      0.0006221]
        glitch_lon = [0.0000717,
                      0.0000912,
                      0.0002761,
                      0.0002626,
                      0.0002807,
                      0.0002049,
                      0.0001304]
        glitch_num = len(glitch_lat)
        self.progress("GPS Glitches:")
        for i in range(1, glitch_num):
            self.progress("glitch %d %.7f %.7f" %
                          (i, glitch_lat[i], glitch_lon[i]))

        # turn south east
        self.progress("turn south east")
        self.set_rc(4, 1580)
        try:
            self.wait_heading(150)
            self.set_rc(4, 1500)
            # fly forward (south east) at least 60m
            self.set_rc(2, 1100)
            self.wait_distance(60)
            self.set_rc(2, 1500)
            # wait for copter to slow down
        except Exception as e:
            if self.use_map:
                self.show_gps_and_sim_positions(False)
            raise e

        # record time and position
        tstart = self.get_sim_time()
        tnow = tstart
        start_pos = self.sim_location()

        # initialise current glitch
        glitch_current = 0
        self.progress("Apply first glitch")
        self.mavproxy.send('param set SIM_GPS_GLITCH_X %.7f\n' %
                           glitch_lat[glitch_current])
        self.mavproxy.send('param set SIM_GPS_GLITCH_Y %.7f\n' %
                           glitch_lon[glitch_current])

        # record position for 30 seconds
        while tnow < tstart + timeout:
            tnow = self.get_sim_time_cached()
            desired_glitch_num = int((tnow - tstart) * 2.2)
            if desired_glitch_num > glitch_current and glitch_current != -1:
                glitch_current = desired_glitch_num
                # turn off glitching if we've reached the end of glitch list
                if glitch_current >= glitch_num:
                    glitch_current = -1
                    self.progress("Completed Glitches")
                    self.set_parameter("SIM_GPS_GLITCH_X", 0)
                    self.set_parameter("SIM_GPS_GLITCH_Y", 0)
                else:
                    self.progress("Applying glitch %u" % glitch_current)
                    # move onto the next glitch
                    self.mavproxy.send('param set SIM_GPS_GLITCH_X %.7f\n' %
                                       glitch_lat[glitch_current])
                    self.mavproxy.send('param set SIM_GPS_GLITCH_Y %.7f\n' %
                                       glitch_lon[glitch_current])

            # start displaying distance moved after all glitches applied
            if glitch_current == -1:
                m = self.mav.recv_match(type='GLOBAL_POSITION_INT',
                                        blocking=True)
                alt = m.alt/1000.0 # mm -> m
                curr_pos = self.sim_location()
                moved_distance = self.get_distance(curr_pos, start_pos)
                self.progress("Alt: %.02f  Moved: %.0f" %
                              (alt, moved_distance))
                if moved_distance > max_distance:
                    raise NotAchievedException(
                        "Moved over %u meters, Failed!" % max_distance)
            else:
                self.drain_mav()

        # disable gps glitch
        if glitch_current != -1:
            self.set_parameter("SIM_GPS_GLITCH_X", 0)
            self.set_parameter("SIM_GPS_GLITCH_Y", 0)
        if self.use_map:
            self.show_gps_and_sim_positions(False)

        self.progress("GPS glitch test passed!"
                      "  stayed within %u meters for %u seconds" %
                      (max_distance, timeout))
        self.do_RTL()
        # re-arming is problematic because the GPS is glitching!
        self.reboot_sitl()

    # fly_gps_glitch_auto_test - fly mission and test reaction to gps glitch
    def fly_gps_glitch_auto_test(self, timeout=180):
        # set-up gps glitch array
        glitch_lat = [0.0002996,
                      0.0006958,
                      0.0009431,
                      0.0009991,
                      0.0009444,
                      0.0007716,
                      0.0006221]
        glitch_lon = [0.0000717,
                      0.0000912,
                      0.0002761,
                      0.0002626,
                      0.0002807,
                      0.0002049,
                      0.0001304]
        glitch_num = len(glitch_lat)
        self.progress("GPS Glitches:")
        for i in range(1, glitch_num):
            self.progress("glitch %d %.7f %.7f" %
                          (i, glitch_lat[i], glitch_lon[i]))

        # Fly mission #1
        self.progress("# Load copter_glitch_mission")
        # load the waypoint count
        num_wp = self.load_mission("copter_glitch_mission.txt")
        if not num_wp:
            raise NotAchievedException("load copter_glitch_mission failed")

        # turn on simulator display of gps and actual position
        if self.use_map:
            self.show_gps_and_sim_positions(True)

        self.progress("test: Fly a mission from 1 to %u" % num_wp)
        self.mavproxy.send('wp set 1\n')

        self.change_mode("STABILIZE")
        self.wait_ready_to_arm()
        self.zero_throttle()
        self.arm_vehicle()

        # switch into AUTO mode and raise throttle
        self.mavproxy.send('switch 4\n')  # auto mode
        self.wait_mode('AUTO')
        self.set_rc(3, 1500)

        # wait until 100m from home
        try:
            self.wait_distance(100, 5, 90)
        except Exception as e:
            if self.use_map:
                self.show_gps_and_sim_positions(False)
            raise e

        # record time and position
        tstart = self.get_sim_time()

        # initialise current glitch
        glitch_current = 0
        self.progress("Apply first glitch")
        self.mavproxy.send('param set SIM_GPS_GLITCH_X %.7f\n' %
                           glitch_lat[glitch_current])
        self.mavproxy.send('param set SIM_GPS_GLITCH_Y %.7f\n' %
                           glitch_lon[glitch_current])

        # record position for 30 seconds
        while glitch_current < glitch_num:
            tnow = self.get_sim_time()
            desired_glitch_num = int((tnow - tstart) * 2.2)
            if desired_glitch_num > glitch_current and glitch_current != -1:
                glitch_current = desired_glitch_num
                # apply next glitch
                if glitch_current < glitch_num:
                    self.progress("Applying glitch %u" % glitch_current)
                    self.mavproxy.send('param set SIM_GPS_GLITCH_X %.7f\n' %
                                       glitch_lat[glitch_current])
                    self.mavproxy.send('param set SIM_GPS_GLITCH_Y %.7f\n' %
                                       glitch_lon[glitch_current])

        # turn off glitching
        self.progress("Completed Glitches")
        self.set_parameter("SIM_GPS_GLITCH_X", 0)
        self.set_parameter("SIM_GPS_GLITCH_Y", 0)

        # continue with the mission
        self.wait_waypoint(0, num_wp-1, timeout=500)

        # wait for arrival back home
        self.mav.recv_match(type='VFR_HUD', blocking=True)
        while self.distance_to_home(use_cached_home=True) > 5:
            if self.get_sim_time_cached() > (tstart + timeout):
                raise AutoTestTimeoutException(
                    ("GPS Glitch testing failed"
                     "- exceeded timeout %u seconds" % timeout))

            self.mav.recv_match(type='VFR_HUD', blocking=True)
            self.progress("Dist from home: %.02f" % self.distance_to_home(use_cached_home=True))

        # turn off simulator display of gps and actual position
        if self.use_map:
            self.show_gps_and_sim_positions(False)

        self.progress("GPS Glitch test Auto completed: passed!")
        self.mav.motors_disarmed_wait()
        # re-arming is problematic because the GPS is glitching!
        self.reboot_sitl()

    #   fly_simple - assumes the simple bearing is initialised to be
    #   directly north flies a box with 100m west, 15 seconds north,
    #   50 seconds east, 15 seconds south
    def fly_simple(self, side=50):
        self.takeoff(10, mode="LOITER")
        # hold position in loiter
        self.mavproxy.send('switch 5\n')  # loiter mode
        self.wait_mode('LOITER')

        # set SIMPLE mode for all flight modes
        self.set_parameter("SIMPLE", 63)

        # switch to stabilize mode
        self.mavproxy.send('switch 6\n')
        self.wait_mode('STABILIZE')
        self.set_rc(3, 1500)

        # fly south 50m
        self.progress("# Flying south %u meters" % side)
        self.set_rc(1, 1300)
        self.wait_distance(side, 5, 60)
        self.set_rc(1, 1500)

        # fly west 8 seconds
        self.progress("# Flying west for 8 seconds")
        self.set_rc(2, 1300)
        tstart = self.get_sim_time()
        while self.get_sim_time_cached() < (tstart + 8):
            self.mav.recv_match(type='VFR_HUD', blocking=True)
        self.set_rc(2, 1500)

        # fly north 25 meters
        self.progress("# Flying north %u meters" % (side/2.0))
        self.set_rc(1, 1700)
        self.wait_distance(side/2, 5, 60)
        self.set_rc(1, 1500)

        # fly east 8 seconds
        self.progress("# Flying east for 8 seconds")
        self.set_rc(2, 1700)
        tstart = self.get_sim_time()
        while self.get_sim_time_cached() < (tstart + 8):
            self.mav.recv_match(type='VFR_HUD', blocking=True)
        self.set_rc(2, 1500)

        # hover in place
        self.hover()

        self.do_RTL()

    # fly_super_simple - flies a circle around home for 45 seconds
    def fly_super_simple(self, timeout=45):
        self.takeoff(10, mode="LOITER")

        # fly forward 20m
        self.progress("# Flying forward 20 meters")
        self.set_rc(2, 1300)
        self.wait_distance(20, 5, 60)
        self.set_rc(2, 1500)

        # set SUPER SIMPLE mode for all flight modes
        self.set_parameter("SUPER_SIMPLE", 63)

        # switch to stabilize mode
        self.change_mode("STABILIZE")
        self.set_rc(3, 1500)

        # start copter yawing slowly
        self.set_rc(4, 1550)

        # roll left for timeout seconds
        self.progress("# rolling left from pilot's POV for %u seconds"
                      % timeout)
        self.set_rc(1, 1300)
        tstart = self.get_sim_time()
        while self.get_sim_time_cached() < (tstart + timeout):
            self.mav.recv_match(type='VFR_HUD', blocking=True)

        # stop rolling and yawing
        self.set_rc(1, 1500)
        self.set_rc(4, 1500)

        # restore simple mode parameters to default
        self.set_parameter("SUPER_SIMPLE", 0)

        # hover in place
        self.hover()

        self.do_RTL()

    # fly_circle - flies a circle with 20m radius
    def fly_circle(self, holdtime=36):
        self.takeoff(10, mode="LOITER")

        # face west
        self.progress("turn west")
        self.set_rc(4, 1580)
        self.wait_heading(270)
        self.set_rc(4, 1500)

        # set CIRCLE radius
        self.set_parameter("CIRCLE_RADIUS", 3000)

        # fly forward (east) at least 100m
        self.set_rc(2, 1100)
        self.wait_distance(100)
        # return pitch stick back to middle
        self.set_rc(2, 1500)

        # set CIRCLE mode
        self.mavproxy.send('switch 1\n')  # circle mode
        self.wait_mode('CIRCLE')

        # wait
        m = self.mav.recv_match(type='VFR_HUD', blocking=True)
        start_altitude = m.alt
        tstart = self.get_sim_time()
        self.progress("Circle at %u meters for %u seconds" %
                      (start_altitude, holdtime))
        while self.get_sim_time_cached() < tstart + holdtime:
            m = self.mav.recv_match(type='VFR_HUD', blocking=True)
            self.progress("heading %d" % m.heading)

        self.progress("CIRCLE OK for %u seconds" % holdtime)

        self.do_RTL()

    def wait_attitude(self, desroll=None, despitch=None, timeout=2, tolerance=10):
        '''wait for an attitude (degrees)'''
        if desroll is None and despitch is None:
            raise ValueError("despitch or desroll must be supplied")
        tstart = self.get_sim_time()
        while True:
            if self.get_sim_time_cached() - tstart > 2:
                raise AutoTestTimeoutException("Failed to achieve attitude")
            m = self.mav.recv_match(type='ATTITUDE', blocking=True)
            roll_deg = math.degrees(m.roll)
            pitch_deg = math.degrees(m.pitch)
            self.progress("wait_att: roll=%f desroll=%s pitch=%f despitch=%s" %
                          (roll_deg, desroll, pitch_deg, despitch))
            if desroll is not None and abs(roll_deg - desroll) > tolerance:
                continue
            if despitch is not None and abs(pitch_deg - despitch) > tolerance:
                continue
            return

    def fly_flip(self):
        ex = None
        try:
            self.mavproxy.send("set streamrate -1\n")
            self.set_message_rate_hz(mavutil.mavlink.MAVLINK_MSG_ID_ATTITUDE, 100)

            self.takeoff(20)
            self.hover()
            old_speedup = self.get_parameter("SIM_SPEEDUP")
            self.set_parameter('SIM_SPEEDUP', 1)
            self.progress("Flipping in roll")
            self.set_rc(1, 1700)
            self.mavproxy.send('mode FLIP\n') # don't wait for heartbeat!
            self.wait_attitude(despitch=0, desroll=45, tolerance=30)
            self.wait_attitude(despitch=0, desroll=90, tolerance=30)
            self.wait_attitude(despitch=0, desroll=-45, tolerance=30)
            self.progress("Waiting for level")
            self.set_rc(1, 1500) # can't change quickly enough!
            self.wait_attitude(despitch=0, desroll=0, tolerance=5)

            self.progress("Regaining altitude")
            self.change_mode('STABILIZE')
            self.set_rc(3, 1800)
            self.wait_for_alt(20)
            self.hover()

            self.progress("Flipping in pitch")
            self.set_rc(2, 1700)
            self.mavproxy.send('mode FLIP\n') # don't wait for heartbeat!
            self.wait_attitude(despitch=45, desroll=0, tolerance=30)
            # can't check roll here as it flips from 0 to -180..
            self.wait_attitude(despitch=90, tolerance=30)
            self.wait_attitude(despitch=-45, tolerance=30)
            self.progress("Waiting for level")
            self.set_rc(1, 1500) # can't change quickly enough!
            self.wait_attitude(despitch=0, desroll=0, tolerance=5)
            self.set_parameter('SIM_SPEEDUP', old_speedup)
            self.change_mode('RTL')
            self.mav.motors_disarmed_wait()
        except Exception as e:
            ex = e
        self.set_message_rate_hz(mavutil.mavlink.MAVLINK_MSG_ID_ATTITUDE, 0)
        sr = self.sitl_streamrate()
        self.mavproxy.send("set streamrate %u\n" % sr)
        if ex is not None:
            raise ex

    # fly_optical_flow_limits - test EKF navigation limiting
    def fly_optical_flow_limits(self):
        ex = None
        self.context_push()
        try:

            self.set_parameter("SIM_FLOW_ENABLE", 1)
            self.set_parameter("FLOW_TYPE", 10)

            self.set_parameter("RNGFND1_TYPE", 1)
            self.set_parameter("RNGFND1_MIN_CM", 0)
            self.set_parameter("RNGFND1_MAX_CM", 4000)
            self.set_parameter("RNGFND1_PIN", 0)
            self.set_parameter("RNGFND1_SCALING", 12.12, epsilon=0.01)

            self.set_parameter("SIM_GPS_DISABLE", 1)
            self.set_parameter("SIM_TERRAIN", 0)

            self.reboot_sitl()

            self.takeoff(alt_min=2, require_absolute=False)

            self.mavproxy.send('mode loiter\n')
            self.wait_mode('LOITER')

            # speed should be limited to <10m/s
            self.set_rc(2, 1000)

            tstart = self.get_sim_time()
            timeout = 60
            while self.get_sim_time_cached() - tstart < timeout:
                m = self.mav.recv_match(type='VFR_HUD', blocking=True)
                spd = m.groundspeed
                max_speed = 8
                self.progress("%0.1f: Low Speed: %f (want <= %u)" %
                              (self.get_sim_time_cached() - tstart,
                               spd,
                               max_speed))
                if spd > max_speed:
                    raise NotAchievedException(("Speed should be limited by"
                                                "EKF optical flow limits"))

            self.progress("Moving higher")
            self.change_alt(60)

            self.wait_groundspeed(10, 100, timeout=60)
        except Exception as e:
            ex = e

        self.set_rc(2, 1500)
        self.context_pop()
        self.disarm_vehicle(force=True)
        self.reboot_sitl()

        if ex is not None:
            raise ex

    # fly_autotune - autotune the virtual vehicle
    def fly_autotune(self):

        self.takeoff(10)

        # hold position in loiter
        self.mavproxy.send('mode autotune\n')
        self.wait_mode('AUTOTUNE')

        tstart = self.get_sim_time()
        sim_time_expected = 5000
        deadline = tstart + sim_time_expected
        while self.get_sim_time_cached() < deadline:
            now = self.get_sim_time_cached()
            m = self.mav.recv_match(type='STATUSTEXT',
                                    blocking=True,
                                    timeout=1)
            if m is None:
                continue
            self.progress("STATUSTEXT (%u<%u): %s" % (now, deadline, m.text))
            if "AutoTune: Success" in m.text:
                self.progress("AUTOTUNE OK (%u seconds)" % (now - tstart))
                # near enough for now:
                self.change_mode('LAND')
                self.mav.motors_disarmed_wait()
                return

        raise NotAchievedException("AUTOTUNE failed (%u seconds)" %
                                   (self.get_sim_time() - tstart))

    # fly_auto_test - fly mission which tests a significant number of commands
    def fly_auto_test(self):
        # Fly mission #1
        self.progress("# Load copter_mission")
        # load the waypoint count
        num_wp = self.load_mission("copter_mission.txt")
        if not num_wp:
            raise NotAchievedException("load copter_mission failed")

        self.progress("test: Fly a mission from 1 to %u" % num_wp)
        self.mavproxy.send('wp set 1\n')

        self.change_mode("LOITER")
        self.wait_ready_to_arm()
        self.arm_vehicle()

        # switch into AUTO mode and raise throttle
        self.change_mode("AUTO")
        self.set_rc(3, 1500)

        # fly the mission
        self.wait_waypoint(0, num_wp-1, timeout=500)

        # set throttle to minimum
        self.zero_throttle()

        # wait for disarm
        self.mav.motors_disarmed_wait()
        self.progress("MOTORS DISARMED OK")

        self.progress("Auto mission completed: passed!")

    def fly_motor_fail(self, fail_servo=0, fail_mul=0.0, holdtime=30):
        """Test flight with reduced motor efficiency"""

        # we only expect an octocopter to survive ATM:
        servo_counts = {
            # 2: 6, # hexa
            3: 8,  # octa
            # 5: 6, # Y6
        }
        frame_class = int(self.get_parameter("FRAME_CLASS"))
        if frame_class not in servo_counts:
            self.progress("Test not relevant for frame_class %u" % frame_class)
            return

        servo_count = servo_counts[frame_class]

        if fail_servo < 0 or fail_servo > servo_count:
            raise ValueError('fail_servo outside range for frame class')

        self.takeoff(10, mode="LOITER")

        self.change_alt(alt_min=50)

        # Get initial values
        start_hud = self.mav.recv_match(type='VFR_HUD', blocking=True)
        start_attitude = self.mav.recv_match(type='ATTITUDE', blocking=True)

        hover_time = 5
        try:
            tstart = self.get_sim_time()
            int_error_alt = 0
            int_error_yaw_rate = 0
            int_error_yaw = 0
            self.progress("Hovering for %u seconds" % hover_time)
            failed = False
            while True:
                now = self.get_sim_time_cached()
                if now - tstart > holdtime + hover_time:
                    break

                servo = self.mav.recv_match(type='SERVO_OUTPUT_RAW',
                                            blocking=True)
                hud = self.mav.recv_match(type='VFR_HUD', blocking=True)
                attitude = self.mav.recv_match(type='ATTITUDE', blocking=True)

                if not failed and now - tstart > hover_time:
                    self.progress("Killing motor %u (%u%%)" %
                                  (fail_servo+1, fail_mul))
                    self.set_parameter("SIM_ENGINE_FAIL", fail_servo)
                    self.set_parameter("SIM_ENGINE_MUL", fail_mul)
                    failed = True

                if failed:
                    self.progress("Hold Time: %f/%f" % (now-tstart, holdtime))

                servo_pwm = [servo.servo1_raw,
                             servo.servo2_raw,
                             servo.servo3_raw,
                             servo.servo4_raw,
                             servo.servo5_raw,
                             servo.servo6_raw,
                             servo.servo7_raw,
                             servo.servo8_raw]

                self.progress("PWM output per motor")
                for i, pwm in enumerate(servo_pwm[0:servo_count]):
                    if pwm > 1900:
                        state = "oversaturated"
                    elif pwm < 1200:
                        state = "undersaturated"
                    else:
                        state = "OK"

                    if failed and i == fail_servo:
                        state += " (failed)"

                    self.progress("servo %u [pwm=%u] [%s]" % (i+1, pwm, state))

                alt_delta = hud.alt - start_hud.alt
                yawrate_delta = attitude.yawspeed - start_attitude.yawspeed
                yaw_delta = attitude.yaw - start_attitude.yaw

                self.progress("Alt=%fm (delta=%fm)" % (hud.alt, alt_delta))
                self.progress("Yaw rate=%f (delta=%f) (rad/s)" %
                              (attitude.yawspeed, yawrate_delta))
                self.progress("Yaw=%f (delta=%f) (deg)" %
                              (attitude.yaw, yaw_delta))

                dt = self.get_sim_time() - now
                int_error_alt += abs(alt_delta/dt)
                int_error_yaw_rate += abs(yawrate_delta/dt)
                int_error_yaw += abs(yaw_delta/dt)
                self.progress("## Error Integration ##")
                self.progress("  Altitude: %fm" % int_error_alt)
                self.progress("  Yaw rate: %f rad/s" % int_error_yaw_rate)
                self.progress("  Yaw: %f deg" % int_error_yaw)
                self.progress("----")

                if int_error_yaw_rate > 0.1:
                    raise NotAchievedException("Vehicle is spinning")

                if alt_delta < -20:
                    raise NotAchievedException("Vehicle is descending")

            self.set_parameter("SIM_ENGINE_FAIL", 0)
            self.set_parameter("SIM_ENGINE_MUL", 1.0)
        except Exception as e:
            self.set_parameter("SIM_ENGINE_FAIL", 0)
            self.set_parameter("SIM_ENGINE_MUL", 1.0)
            raise e

        self.do_RTL()

    def fly_vision_position(self):
        """Disable GPS navigation, enable Vicon input."""
        # scribble down a location we can set origin to:

        self.progress("Waiting for location")
        self.mavproxy.send('switch 6\n')  # stabilize mode
        self.wait_heartbeat()
        self.wait_mode('STABILIZE')
        self.wait_ready_to_arm()

        old_pos = self.mav.recv_match(type='GLOBAL_POSITION_INT', blocking=True)
        print("old_pos=%s" % str(old_pos))

        self.context_push()

        ex = None
        try:
            self.set_parameter("GPS_TYPE", 0)
            self.set_parameter("EK2_GPS_TYPE", 3)
            self.set_parameter("SERIAL5_PROTOCOL", 1)
            self.reboot_sitl()
            # without a GPS or some sort of external prompting, AP
            # doesn't send system_time messages.  So prompt it:
            self.mav.mav.system_time_send(int(time.time() * 1000000), 0)
            self.mav.mav.set_gps_global_origin_send(1,
                                                    old_pos.lat,
                                                    old_pos.lon,
                                                    old_pos.alt)
            self.progress("Waiting for non-zero-lat")
            tstart = self.get_sim_time()
            while True:
                gpi = self.mav.recv_match(type='GLOBAL_POSITION_INT',
                                          blocking=True)
                # self.progress("gpi=%s" % str(gpi))
                if gpi.lat != 0:
                    break

                if self.get_sim_time_cached() - tstart > 20:
                    raise AutoTestTimeoutException("Did not get non-zero lat")

            self.takeoff()
            self.set_rc(1, 1600)
            tstart = self.get_sim_time()
            while True:
                vicon_pos = self.mav.recv_match(type='VICON_POSITION_ESTIMATE',
                                                blocking=True)
                # print("vpe=%s" % str(vicon_pos))
                self.mav.recv_match(type='GLOBAL_POSITION_INT',
                                    blocking=True)
                # self.progress("gpi=%s" % str(gpi))
                if vicon_pos.x > 40:
                    break

                if self.get_sim_time_cached() - tstart > 100:
                    raise AutoTestTimeoutException("Vicon showed no movement")

            # recenter controls:
            self.set_rc(1, 1500)
            self.progress("# Enter RTL")
            self.mavproxy.send('switch 3\n')
            self.set_rc(3, 1500)
            tstart = self.get_sim_time()
            while True:
                if self.get_sim_time_cached() - tstart > 200:
                    raise NotAchievedException("Did not disarm")
                self.mav.recv_match(type='GLOBAL_POSITION_INT',
                                    blocking=True)
                # print("gpi=%s" % str(gpi))
                self.mav.recv_match(type='SIMSTATE',
                                    blocking=True)
                # print("ss=%s" % str(ss))
                # wait for RTL disarm:
                if not self.armed():
                    break

        except Exception as e:
            self.progress("Exception caught")
            ex = e

        self.context_pop()
        self.zero_throttle()
        self.reboot_sitl()

        if ex is not None:
            raise ex

    def fly_rtl_speed(self):
        """Test RTL Speed parameters"""
        rtl_speed_ms = 7
        wpnav_speed_ms = 4
        wpnav_accel_mss = 3
        tolerance = 0.5
        self.load_mission("copter_rtl_speed.txt")
        self.set_parameter('WPNAV_ACCEL', wpnav_accel_mss * 100)
        self.set_parameter('RTL_SPEED', rtl_speed_ms * 100)
        self.set_parameter('WPNAV_SPEED', wpnav_speed_ms * 100)
        self.change_mode('LOITER')
        self.wait_ready_to_arm()
        self.arm_vehicle()
        self.change_mode('AUTO')
        self.set_rc(3, 1600)
        self.wait_altitude(19, 25, relative=True)
        self.wait_groundspeed(wpnav_speed_ms-tolerance, wpnav_speed_ms+tolerance)
        self.monitor_groundspeed(wpnav_speed_ms, timeout=20)
        self.change_mode('RTL')
        self.wait_groundspeed(rtl_speed_ms-tolerance, rtl_speed_ms+tolerance)
        self.monitor_groundspeed(rtl_speed_ms, timeout=5)
        self.change_mode('AUTO')
        self.wait_groundspeed(0-tolerance, 0+tolerance)
        self.wait_groundspeed(wpnav_speed_ms-tolerance, wpnav_speed_ms+tolerance)
        self.monitor_groundspeed(wpnav_speed_ms, timeout=5)
        self.change_mode('RTL')
        self.mav.motors_disarmed_wait()

    def fly_nav_delay(self):
        """Fly a simple mission that has a delay in it."""

        self.load_mission("copter_nav_delay.txt")

        self.set_parameter("DISARM_DELAY", 0)

        self.change_mode("LOITER")
        self.wait_ready_to_arm()

        self.arm_vehicle()
        self.change_mode("AUTO")
        self.set_rc(3, 1600)
        count_start = -1
        count_stop = -1
        tstart = self.get_sim_time()
        last_mission_current_msg = 0
        last_seq = None
        while self.armed(): # we RTL at end of mission
            now = self.get_sim_time_cached()
            if now - tstart > 120:
                raise AutoTestTimeoutException("Did not disarm as expected")
            m = self.mav.recv_match(type='MISSION_CURRENT', blocking=True)
            at_delay_item = ""
            if m.seq == 3:
                at_delay_item = "(At delay item)"
                if count_start == -1:
                    count_start = now
            if ((now - last_mission_current_msg) > 1 or m.seq != last_seq):
                dist = None
                x = self.mav.messages.get("NAV_CONTROLLER_OUTPUT", None)
                if x is not None:
                    dist = x.wp_dist
                    self.progress("MISSION_CURRENT.seq=%u dist=%s %s" %
                                  (m.seq, dist, at_delay_item))
                last_mission_current_msg = self.get_sim_time_cached()
                last_seq = m.seq
            if m.seq > 3:
                if count_stop == -1:
                    count_stop = now
        calculated_delay = count_stop - count_start
        want_delay = 59 # should reflect what's in the mission file
        self.progress("Stopped for %u seconds (want >=%u seconds)" %
                      (calculated_delay, want_delay))
        if calculated_delay < want_delay:
            raise NotAchievedException("Did not delay for long enough")

    def test_rangefinder(self):
        ex = None
        self.context_push()
        self.progress("Making sure we don't ordinarily get RANGEFINDER")
        try:
            m = self.mav.recv_match(type='RANGEFINDER',
                                    blocking=True,
                                    timeout=5)
        except Exception as e:
            print("Caught exception %s" % str(e))

        if m is not None:
            raise NotAchievedException("Received unexpected RANGEFINDER msg")

        # may need to force a rotation if some other test has used the
        # rangefinder...
        self.progress("Ensure no RFND messages in log")
        if self.current_onboard_log_contains_message("RFND"):
            raise NotAchievedException("Found unexpected RFND message")

        try:
            self.set_parameter("RNGFND1_TYPE", 1)
            self.set_parameter("RNGFND1_MIN_CM", 0)
            self.set_parameter("RNGFND1_MAX_CM", 4000)
            self.set_parameter("RNGFND1_PIN", 0)
            self.set_parameter("RNGFND1_SCALING", 12.12)
            self.set_parameter("RC9_OPTION", 10) # rangefinder
            self.set_rc(9, 2000)

            self.reboot_sitl()

            self.progress("Making sure we now get RANGEFINDER messages")
            m = self.mav.recv_match(type='RANGEFINDER',
                                    blocking=True,
                                    timeout=10)
            if m is None:
                raise NotAchievedException("Did not get expected RANGEFINDER msg")

            self.progress("Checking RangeFinder is marked as enabled in mavlink")
            m = self.mav.recv_match(type='SYS_STATUS',
                                    blocking=True,
                                    timeout=10)
            flags = m.onboard_control_sensors_enabled
            if not flags & mavutil.mavlink.MAV_SYS_STATUS_SENSOR_LASER_POSITION:
                raise NotAchievedException("Laser not enabled in SYS_STATUS")
            self.progress("Disabling laser using switch")
            self.set_rc(9, 1000)
            self.delay_sim_time(1)
            self.progress("Checking RangeFinder is marked as disabled in mavlink")
            m = self.mav.recv_match(type='SYS_STATUS',
                                    blocking=True,
                                    timeout=10)
            flags = m.onboard_control_sensors_enabled
            if flags & mavutil.mavlink.MAV_SYS_STATUS_SENSOR_LASER_POSITION:
                raise NotAchievedException("Laser enabled in SYS_STATUS")

            self.progress("Re-enabling rangefinder")
            self.set_rc(9, 2000)
            self.delay_sim_time(1)
            m = self.mav.recv_match(type='SYS_STATUS',
                                    blocking=True,
                                    timeout=10)
            flags = m.onboard_control_sensors_enabled
            if not flags & mavutil.mavlink.MAV_SYS_STATUS_SENSOR_LASER_POSITION:
                raise NotAchievedException("Laser not enabled in SYS_STATUS")

            self.takeoff(10, mode="LOITER")

            m_r = self.mav.recv_match(type='RANGEFINDER',
                                      blocking=True)
            m_p = self.mav.recv_match(type='GLOBAL_POSITION_INT',
                                      blocking=True)

            if abs(m_r.distance - m_p.relative_alt/1000) > 1:
                raise NotAchievedException("rangefinder/global position int mismatch")

            self.land_and_disarm()

            if not self.current_onboard_log_contains_message("RFND"):
                raise NotAchievedException("Did not see expected RFND message")

        except Exception as e:
            self.progress("Exception caught")
            ex = e
        self.context_pop()
        self.reboot_sitl()
        if ex is not None:
            raise ex

    def test_parachute(self):

        self.set_rc(9, 1000)
        self.set_parameter("CHUTE_ENABLED", 1)
        self.set_parameter("CHUTE_TYPE", 10)
        self.set_parameter("SERVO9_FUNCTION", 27)
        self.set_parameter("SIM_PARA_ENABLE", 1)
        self.set_parameter("SIM_PARA_PIN", 9)

        self.progress("Test triggering parachute in mission")
        self.load_mission("copter_parachute_mission.txt")
        self.change_mode('LOITER')
        self.wait_ready_to_arm()
        self.arm_vehicle()
        self.change_mode('AUTO')
        self.set_rc(3, 1600)
        self.mavproxy.expect('BANG')
        self.reboot_sitl()

        self.progress("Test triggering with mavlink message")
        self.takeoff(20)
        self.run_cmd(mavutil.mavlink.MAV_CMD_DO_PARACHUTE,
                     2, # release
                     0,
                     0,
                     0,
                     0,
                     0,
                     0)
        self.mavproxy.expect('BANG')
        self.reboot_sitl()

        self.progress("Testing three-position switch")
        self.set_parameter("RC9_OPTION", 23) # parachute 3pos

        self.progress("Test manual triggering")
        self.takeoff(20)
        self.set_rc(9, 2000)
        self.mavproxy.expect('BANG')
        self.set_rc(9, 1000)
        self.reboot_sitl()

        self.context_push()
        self.progress("Crashing with 3pos switch in enable position")
        self.takeoff(40)
        self.set_rc(9, 1500)
        self.set_parameter("SIM_ENGINE_MUL", 0)
        self.set_parameter("SIM_ENGINE_FAIL", 1)
        self.mavproxy.expect('BANG')
        self.set_rc(9, 1000)
        self.reboot_sitl()
        self.context_pop();

        self.progress("Crashing with 3pos switch in disable position")
        loiter_alt = 10
        self.takeoff(loiter_alt, mode='LOITER')
        self.set_rc(9, 1100)
        self.set_parameter("SIM_ENGINE_MUL", 0)
        self.set_parameter("SIM_ENGINE_FAIL", 1)
        tstart = self.get_sim_time()
        while self.get_sim_time_cached() < tstart + 5:
            m = self.mav.recv_match(type='STATUSTEXT', blocking=True, timeout=1)
            if m is None:
                continue
            if "BANG" in m.text:
                self.set_rc(9, 1000)
                self.reboot_sitl()
                raise NotAchievedException("Parachute deployed when disabled")
        self.set_rc(9, 1000)
        self.reboot_sitl()

    def fly_precision_sitl(self):
        """Use SITL PrecLand backend precision messages to land aircraft."""

        self.context_push()

        ex = None
        try:
            self.set_parameter("PLND_ENABLED", 1)
            self.fetch_parameters()
            self.set_parameter("PLND_TYPE", 4)

            self.set_parameter("RNGFND1_TYPE", 1)
            self.set_parameter("RNGFND1_MIN_CM", 0)
            self.set_parameter("RNGFND1_MAX_CM", 4000)
            self.set_parameter("RNGFND1_PIN", 0)
            self.set_parameter("RNGFND1_SCALING", 12)
            self.set_parameter("SIM_SONAR_SCALE", 12)

            start = self.mav.location()
            target = start
            (target.lat, target.lng) = mavextra.gps_offset(start.lat, start.lng, 4, -4)
            self.progress("Setting target to %f %f" % (target.lat, target.lng))

            self.set_parameter("SIM_PLD_ENABLE", 1)
            self.set_parameter("SIM_PLD_LAT", target.lat)
            self.set_parameter("SIM_PLD_LON", target.lng)
            self.set_parameter("SIM_PLD_HEIGHT", 0)
            self.set_parameter("SIM_PLD_ALT_LMT", 15)
            self.set_parameter("SIM_PLD_DIST_LMT", 10)

            self.reboot_sitl()

            self.progress("Waiting for location")
            old_pos = self.mav.location()
            self.zero_throttle()
            self.takeoff(10, 1800)
            self.change_mode("LAND")
            self.mav.motors_disarmed_wait()
            self.mav.recv_match(type='GLOBAL_POSITION_INT', blocking=True)
            new_pos = self.mav.location()
            delta = self.get_distance(target, new_pos)
            self.progress("Landed %f metres from target position" % delta)
            max_delta = 1
            if delta > max_delta:
                raise NotAchievedException("Did not land close enough to target position (%fm > %fm" % (delta, max_delta))

            if not self.current_onboard_log_contains_message("PL"):
                raise NotAchievedException("Did not see expected PL message")

        except Exception as e:
            self.progress("Exception caught (%s)" % str(e))
            ex = e

        self.zero_throttle()
        self.context_pop()
        self.reboot_sitl()
        self.progress("All done")

        if ex is not None:
            raise ex

    def get_system_clock_utc(self, time_seconds):
        # this is a copy of ArduPilot's AP_RTC function!
        # separate time into ms, sec, min, hour and days but all expressed
        # in milliseconds
        time_ms = time_seconds * 1000
        ms = time_ms % 1000
        sec_ms = (time_ms % (60 * 1000)) - ms
        min_ms = (time_ms % (60 * 60 * 1000)) - sec_ms - ms
        hour_ms = (time_ms % (24 * 60 * 60 * 1000)) - min_ms - sec_ms - ms

        # convert times as milliseconds into appropriate units
        secs = sec_ms / 1000
        mins = min_ms / (60 * 1000)
        hours = hour_ms / (60 * 60 * 1000)
        return (hours, mins, secs, 0)

    def calc_delay(self, seconds):
        # delay-for-seconds has to be long enough that we're at the
        # waypoint before that time.  Otherwise we'll try to wait a
        # day....
        (hours,
         mins,
         secs,
         ms) = self.get_system_clock_utc(seconds)
        self.progress("Now is %uh %um %us" % (hours, mins, secs))
        secs += 17 # add seventeen seconds
        if secs >= 60:
            secs %= 60
            mins += 1 # add sixty seconds
        mins += 1
        if mins >= 60:
            mins %= 60
            hours += 1
        if hours >= 24:
            hours %= 24
        return (hours, mins, secs, 0)

    def reset_delay_item_seventyseven(self, seq):
        while True:
            self.progress("Requesting request for seq %u" % (seq,))
            self.mav.mav.mission_write_partial_list_send(1, # target system
                                                         1, # target component
                                                         seq, # start index
                                                         seq)
            req = self.mav.recv_match(type='MISSION_REQUEST',
                                      blocking=True,
                                      timeout=1)
            if req is not None and req.seq == seq:
                if req.get_srcSystem() == 255:
                    self.progress("Shutup MAVProxy")
                    continue
                # notionally this might be in the message cache before
                # we prompt for it... *shrug*
                break

        # we have received a request for the item.  Supply it:

        frame = mavutil.mavlink.MAV_FRAME_GLOBAL_RELATIVE_ALT_INT
        command = mavutil.mavlink.MAV_CMD_NAV_DELAY
        # retrieve mission item and check it:
        tried_set = False
        hours = None
        mins = None
        secs = None
        while True:
            self.progress("Requesting item")
            self.mav.mav.mission_request_send(1,
                                              1,
                                              seq)
            st = self.mav.recv_match(type='MISSION_ITEM',
                                     blocking=True,
                                     timeout=1)
            if st is None:
                continue

            print("Item: %s" % str(st))
            have_match = (tried_set and
                          st.seq == seq and
                          st.command == command and
                          st.param2 == hours and
                          st.param3 == mins and
                          st.param4 == secs)
            if have_match:
                return

            self.progress("Mission mismatch")

            m = None
            tstart = self.get_sim_time()
            while True:
                if self.get_sim_time_cached() - tstart > 3:
                    raise NotAchievedException(
                        "Did not receive MISSION_REQUEST")
                self.mav.mav.mission_write_partial_list_send(1,
                                                             1,
                                                             seq,
                                                             seq)
                m = self.mav.recv_match(type='MISSION_REQUEST',
                                        blocking=True,
                                        timeout=1)
                if m is None:
                    continue
                if m.seq != st.seq:
                    continue
                break

            self.progress("Sending absolute-time mission item")

            # we have to change out the delay time...
            now = self.mav.messages["SYSTEM_TIME"]
            if now is None:
                raise PreconditionFailedException("Never got SYSTEM_TIME")
            if now.time_unix_usec == 0:
                raise PreconditionFailedException("system time is zero")
            (hours, mins, secs, ms) = self.calc_delay(
                now.time_unix_usec/1000000)

            self.progress("Delay until %uh %um %us" %
                          (hours, mins, secs))

            self.mav.mav.mission_item_send(
                1, # target system
                1, # target component
                seq, # seq
                frame, # frame
                command, # command
                0, # current
                1, # autocontinue
                0, # p1 (relative seconds)
                hours, # p2
                mins, # p3
                secs, # p4
                0, # p5
                0, # p6
                0) # p7
            tried_set = True
            ack = self.mav.recv_match(type='MISSION_ACK',
                                      blocking=True,
                                      timeout=1)
            self.progress("Received ack: %s" % str(ack))

    def fly_nav_delay_abstime(self):
        """fly a simple mission that has a delay in it"""

        self.load_mission("copter_nav_delay.txt")

        self.change_mode("LOITER")

        self.wait_ready_to_arm()

        delay_item_seq = 3
        self.reset_delay_item_seventyseven(delay_item_seq)
        delay_for_seconds = 77
        reset_at_m = self.mav.recv_match(type='SYSTEM_TIME', blocking=True)
        reset_at = reset_at_m.time_unix_usec/1000000

        self.arm_vehicle()
        self.change_mode("AUTO")
        self.set_rc(3, 1600)
        count_stop = -1
        tstart = self.get_sim_time()
        while self.armed(): # we RTL at end of mission
            now = self.get_sim_time_cached()
            if now - tstart > 120:
                raise AutoTestTimeoutException("Did not disarm as expected")
            m = self.mav.recv_match(type='MISSION_CURRENT', blocking=True)
            at_delay_item = ""
            if m.seq == delay_item_seq:
                at_delay_item = "(delay item)"
            self.progress("MISSION_CURRENT.seq=%u %s" % (m.seq, at_delay_item))
            if m.seq > delay_item_seq:
                if count_stop == -1:
                    count_stop_m = self.mav.recv_match(type='SYSTEM_TIME',
                                                       blocking=True)
                    count_stop = count_stop_m.time_unix_usec/1000000
        calculated_delay = count_stop - reset_at
        error = abs(calculated_delay - delay_for_seconds)
        self.progress("Stopped for %u seconds (want >=%u seconds)" %
                      (calculated_delay, delay_for_seconds))
        if error > 2:
            raise NotAchievedException("delay outside expectations")

    def fly_nav_takeoff_delay_abstime(self):
        """make sure taking off at a specific time works"""
        self.load_mission("copter_nav_delay_takeoff.txt")

        self.change_mode("LOITER")
        self.wait_ready_to_arm()

        delay_item_seq = 2
        self.reset_delay_item_seventyseven(delay_item_seq)
        delay_for_seconds = 77
        reset_at = self.get_sim_time_cached()

        self.arm_vehicle()
        self.change_mode("AUTO")

        self.set_rc(3, 1600)

        # should not take off for about least 77 seconds
        tstart = self.get_sim_time()
        took_off = False
        while self.armed():
            now = self.get_sim_time_cached()
            if now - tstart > 200:
                # timeout
                break
            m = self.mav.recv_match(type='MISSION_CURRENT', blocking=True)
            now = self.get_sim_time_cached()
            self.progress("%s" % str(m))
            if m.seq > delay_item_seq:
                if not took_off:
                    took_off = True
                    delta_time = now - reset_at
                    if abs(delta_time - delay_for_seconds) > 2:
                        raise NotAchievedException((
                            "Did not take off on time "
                            "measured=%f want=%f" %
                            (delta_time, delay_for_seconds)))

        if not took_off:
            raise NotAchievedException("Did not take off")

    def fly_zigzag_mode(self):
        '''test zigzag mode'''

        # set channel 8 for zigzag savewp and recentre it
        self.set_parameter("RC8_OPTION", 61)

        self.takeoff(alt_min=5, mode='LOITER')

        ZIGZAG = 24
        j=0
        while j<4:  # conduct test for all 4 directions
            self.set_rc(8, 1500)
            self.set_rc(4, 1420)
            self.wait_heading(352-j*90)  # align heading with the run-way
            self.set_rc(4, 1500)
            self.change_mode(ZIGZAG)
            self.set_rc(8, 1100)  # record point A
            self.set_rc(1, 1700)  # fly side-way for 20m
            self.wait_distance(20)
            self.set_rc(1, 1500)
            self.wait_groundspeed(0, 0.20)   # wait until the copter slows down
            self.set_rc(8, 1500)    # pilot always have to cross mid position when changing for low to high position
            self.set_rc(8, 1900)    # record point B

            i=1
            while i<2:                 # run zigzag A->B and B->A for 5 times
                self.set_rc(2, 1300)    # fly forward for 10 meter
                self.wait_distance(10)
                self.set_rc(2, 1500)    # re-centre pitch rc control
                self.wait_groundspeed(0, 0.2)   #wait until the copter slows down
                self.set_rc(8, 1500)    # switch to mid position
                self.set_rc(8, 1100)    # auto execute vector BA
                self.wait_distance(17)  # wait for it to finish
                self.wait_groundspeed(0, 0.2)   #wait until the copter slows down

                self.set_rc(2, 1300)    # fly forward for 10 meter
                self.wait_distance(10)
                self.set_rc(2, 1500)    # re-centre pitch rc control
                self.wait_groundspeed(0, 0.2)   #wait until the copter slows down
                self.set_rc(8, 1500)    # switch to mid position
                self.set_rc(8, 1900)    # auto execute vector AB
                self.wait_distance(17)  # wait for it to finish
                self.wait_groundspeed(0, 0.2)   #wait until the copter slows down
                i=i+1
            # test the case when pilot switch to manual control during the auto flight
            self.set_rc(2, 1300)    # fly forward for 10 meter
            self.wait_distance(10)
            self.set_rc(2, 1500)    # re-centre pitch rc control
            self.wait_groundspeed(0, 0.2)   #wait until the copter slows down
            self.set_rc(8, 1500)    # switch to mid position
            self.set_rc(8, 1100)    # switch to low position, auto execute vector BA
            self.wait_distance(8)   # purposely switch to manual halfway
            self.set_rc(8, 1500)
            self.wait_groundspeed(0, 0.2)   # copter should slow down here
            self.set_rc(2, 1300)    # manual control to fly forward
            self.wait_distance(8)
            self.set_rc(2, 1500)    # re-centre pitch rc control
            self.wait_groundspeed(0, 0.2)   # wait until the copter slows down
            self.set_rc(8, 1100)    # copter should continue mission here
            self.wait_distance(8)   # wait for it to finish rest of BA
            self.wait_groundspeed(0, 0.2)   #wait until the copter slows down
            self.set_rc(8, 1500)    # switch to mid position
            self.set_rc(8, 1900)    # switch to execute AB again
            self.wait_distance(17)  # wait for it to finish
            self.wait_groundspeed(0, 0.2)   # wait until the copter slows down
            self.change_mode('LOITER')
            j=j+1

        self.do_RTL()


    def test_setting_modes_via_modeswitch(self):
        self.context_push()
        ex = None
        try:
            fltmode_ch = 5
            self.set_parameter("FLTMODE_CH", fltmode_ch)
            self.set_rc(fltmode_ch, 1000) # PWM for mode1
            testmodes = [("FLTMODE1", 4, "GUIDED", 1165),
                         ("FLTMODE2", 13, "SPORT", 1295),
                         ("FLTMODE3", 6, "RTL", 1425),
                         ("FLTMODE4", 7, "CIRCLE", 1555),
                         ("FLTMODE5", 1, "ACRO", 1685),
                         ("FLTMODE6", 17, "BRAKE", 1815),
                         ]
            for mode in testmodes:
                (parm, parm_value, name, pwm) = mode
                self.set_parameter(parm, parm_value)

            for mode in reversed(testmodes):
                (parm, parm_value, name, pwm) = mode
                self.set_rc(fltmode_ch, pwm)
                self.wait_mode(name)

            for mode in testmodes:
                (parm, parm_value, name, pwm) = mode
                self.set_rc(fltmode_ch, pwm)
                self.wait_mode(name)

            for mode in reversed(testmodes):
                (parm, parm_value, name, pwm) = mode
                self.set_rc(fltmode_ch, pwm)
                self.wait_mode(name)

            self.mavproxy.send('switch 6\n')
            self.wait_mode("BRAKE")
            self.mavproxy.send('switch 5\n')
            self.wait_mode("ACRO")

        except Exception as e:
            self.progress("Exception caught")
            ex = e

        self.context_pop()

        if ex is not None:
            raise ex

    def test_setting_modes_via_auxswitch(self):
        self.context_push()
        ex = None
        try:
            fltmode_ch = int(self.get_parameter("FLTMODE_CH"))
            self.set_rc(fltmode_ch, 1000)
            self.wait_mode("CIRCLE")
            self.set_rc(9, 1000)
            self.set_rc(10, 1000)
            self.set_parameter("RC9_OPTION", 18) # land
            self.set_parameter("RC10_OPTION", 55) # guided
            self.set_rc(9, 1900)
            self.wait_mode("LAND")
            self.set_rc(10, 1900)
            self.wait_mode("GUIDED")
            self.set_rc(10, 1000) # this re-polls the mode switch
            self.wait_mode("CIRCLE")
        except Exception as e:
            self.progress("Exception caught")
            ex = e

        self.context_pop()

        if ex is not None:
            raise ex

    def fly_guided_stop(self,
                        timeout=20,
                        groundspeed_tolerance=0.05,
                        climb_tolerance=0.001):
        """stop the vehicle moving in guided mode"""
        self.progress("Stopping vehicle")
        tstart = self.get_sim_time()
        while True:
            if self.get_sim_time_cached() - tstart > timeout:
                raise NotAchievedException("Vehicle did not stop")
            # send a position-control command
            self.mav.mav.set_position_target_local_ned_send(
                0, # timestamp
                1, # target system_id
                1, # target component id
                mavutil.mavlink.MAV_FRAME_BODY_NED,
                0b1111111111111000, # mask specifying use-only-x-y-z
                0, # x
                0, # y
                0, # z
                0, # vx
                0, # vy
                0, # vz
                0, # afx
                0, # afy
                0, # afz
                0, # yaw
                0, # yawrate
            )
            m = self.mav.recv_match(type='VFR_HUD', blocking=True)
            print("%s" % str(m))
            if (m.groundspeed < groundspeed_tolerance and
                m.climb < climb_tolerance):
                break

    def fly_guided_move_global_relative_alt(self, lat, lon, alt):
        startpos = self.mav.recv_match(type='GLOBAL_POSITION_INT',
                                       blocking=True)

        tstart = self.get_sim_time()
        while True:
            if self.get_sim_time_cached() - tstart > 200:
                raise NotAchievedException("Did not move far enough")
            # send a position-control command
            self.mav.mav.set_position_target_global_int_send(
                0, # timestamp
                1, # target system_id
                1, # target component id
                mavutil.mavlink.MAV_FRAME_GLOBAL_RELATIVE_ALT_INT,
                0b1111111111111000, # mask specifying use-only-lat-lon-alt
                lat, # lat
                lon, # lon
                alt, # alt
                0, # vx
                0, # vy
                0, # vz
                0, # afx
                0, # afy
                0, # afz
                0, # yaw
                0, # yawrate
            )
            pos = self.mav.recv_match(type='GLOBAL_POSITION_INT',
                                      blocking=True)
            delta = self.get_distance_int(startpos, pos)
            self.progress("delta=%f (want >10)" % delta)
            if delta > 10:
                break

    def fly_guided_move_local(self, x, y, z_up, timeout=100):
        """move the vehicle using MAVLINK_MSG_ID_SET_POSITION_TARGET_LOCAL_NED"""
        startpos = self.mav.recv_match(type='LOCAL_POSITION_NED', blocking=True)
        self.progress("startpos=%s" % str(startpos))

        tstart = self.get_sim_time()
        while True:
            if self.get_sim_time_cached() - tstart > timeout:
                raise NotAchievedException("Did not start to move")
            # send a position-control command
            self.mav.mav.set_position_target_local_ned_send(
                0, # timestamp
                1, # target system_id
                1, # target component id
                mavutil.mavlink.MAV_FRAME_LOCAL_NED,
                0b1111111111111000, # mask specifying use-only-x-y-z
                x, # x
                y, # y
                -z_up,# z
                0, # vx
                0, # vy
                0, # vz
                0, # afx
                0, # afy
                0, # afz
                0, # yaw
                0, # yawrate
            )
            m = self.mav.recv_match(type='VFR_HUD', blocking=True)
            print("%s" % m)
            if m.groundspeed > 0.5:
                break

        self.progress("Waiting for vehicle to stop...")
        self.wait_groundspeed(1, 100, timeout=timeout)

        stoppos = self.mav.recv_match(type='LOCAL_POSITION_NED', blocking=True)
        self.progress("stop_pos=%s" % str(stoppos))

        x_achieved = stoppos.x - startpos.x
        if x_achieved - x > 1:
            raise NotAchievedException("Did not achieve x position: want=%f got=%f" % (x, x_achieved))

        y_achieved = stoppos.y - startpos.y
        if y_achieved - y > 1:
            raise NotAchievedException("Did not achieve y position: want=%f got=%f" % (y, y_achieved))

        z_achieved = stoppos.z - startpos.z
        if z_achieved - z_up > 1:
            raise NotAchievedException("Did not achieve z position: want=%f got=%f" % (z_up, z_achieved))

    def test_guided_local_position_target(self, x, y, z_up):
        """ Check target position being received by vehicle """
        # set POSITION_TARGET_LOCAL_NED message rate using SET_MESSAGE_INTERVAL
        self.progress("Setting local target in NED: (%f, %f, %f)" % (x, y, -z_up))
        self.progress("Setting rate to 1 Hz")
        self.set_message_rate_hz(mavutil.mavlink.MAVLINK_MSG_ID_POSITION_TARGET_LOCAL_NED, 1)
        # set position target
        self.mav.mav.set_position_target_local_ned_send(
                0, # timestamp
                1, # target system_id
                1, # target component id
                mavutil.mavlink.MAV_FRAME_LOCAL_NED,
                0b1111111111111000, # mask specifying use only xyz
                x, # x
                y, # y
                -z_up, # z
                0, # vx
                0, # vy
                0, # vz
                0, # afx
                0, # afy
                0, # afz
                0, # yaw
                0, # yawrate
            )
        m = self.mav.recv_match(type='POSITION_TARGET_LOCAL_NED', blocking=True, timeout=2)
        self.progress("Received local target: %s" % str(m))
        
        if not (m.type_mask == 0xFFF8 or m.type_mask == 0x0FF8):
            raise NotAchievedException("Did not receive proper mask: expected=65528 or 4088, got=%u" % m.type_mask)

        if x - m.x > 0.1:
            raise NotAchievedException("Did not receive proper target position x: wanted=%f got=%f" % (x, m.x))

        if y - m.y > 0.1:
            raise NotAchievedException("Did not receive proper target position y: wanted=%f got=%f" % (y, m.y))

        if z_up - (-m.z) > 0.1:
            raise NotAchievedException("Did not receive proper target position z: wanted=%f got=%f" % (z_up, -m.z))

    def test_guided_local_velocity_target(self, vx, vy, vz_up, timeout=3):
        " Check local target velocity being recieved by vehicle "
        self.progress("Setting local NED velocity target: (%f, %f, %f)" %(vx, vy, -vz_up))
        self.progress("Setting POSITION_TARGET_LOCAL_NED message rate to 10Hz")
        self.set_message_rate_hz(mavutil.mavlink.MAVLINK_MSG_ID_POSITION_TARGET_LOCAL_NED, 10)

        # Drain old messages and ignore the ramp-up to the required target velocity
        tstart = self.get_sim_time()
        while self.get_sim_time_cached() - tstart < timeout:
            # send velocity-control command
            self.mav.mav.set_position_target_local_ned_send(
                    0, # timestamp
                    1, # target system_id
                    1, # target component id
                    mavutil.mavlink.MAV_FRAME_LOCAL_NED,
                    0b1111111111000111, # mask specifying use only vx,vy,vz
                    0, # x
                    0, # y
                    0, # z
                    vx, # vx
                    vy, # vy
                    -vz_up, # vz
                    0, # afx
                    0, # afy
                    0, # afz
                    0, # yaw
                    0, # yawrate
                )
            m = self.mav.recv_match(type='POSITION_TARGET_LOCAL_NED', blocking=True, timeout=1)

            if m is None:
                raise NotAchievedException("Did not receive any message for 1 sec")

            self.progress("Received local target: %s" % str(m))

        # Check the last received message
        if not (m.type_mask == 0xFFC7 or m.type_mask == 0x0FC7):
            raise NotAchievedException("Did not receive proper mask: expected=65479 or 4039, got=%u" % m.type_mask)

        if vx - m.vx > 0.1:
            raise NotAchievedException("Did not receive proper target velocity vx: wanted=%f got=%f" % (vx, m.vx))

        if vy - m.vy > 0.1:
            raise NotAchievedException("Did not receive proper target velocity vy: wanted=%f got=%f" % (vy, m.vy))

        if vz_up - (-m.vz) > 0.1:
            raise NotAchievedException("Did not receive proper target velocity vz: wanted=%f got=%f" % (vz_up, -m.vz))

        self.progress("Received proper target velocity commands")

    def test_position_target_message_mode(self):
        " Ensure that POSITION_TARGET_LOCAL_NED messages are sent in Guided Mode only "
        self.hover()
        self.change_mode('LOITER')
        self.progress("Setting POSITION_TARGET_LOCAL_NED message rate to 10Hz")
        self.set_message_rate_hz(mavutil.mavlink.MAVLINK_MSG_ID_POSITION_TARGET_LOCAL_NED, 10)

        tstart = self.get_sim_time()
        while self.get_sim_time_cached() < tstart + 5:
            m = self.mav.recv_match(type='POSITION_TARGET_LOCAL_NED', blocking=True, timeout=1)
            if m is None:
                continue

            raise NotAchievedException("Received POSITION_TARGET message in LOITER mode: %s" % str(m))

        self.progress("Did not receive any POSITION_TARGET_LOCAL_NED message in LOITER mode. Success")

    def earth_to_body(self, vector):
        m = self.mav.messages["ATTITUDE"]
        x = rotmat.Vector3(m.roll, m.pitch, m.yaw)
#        print('r=%f p=%f y=%f' % (m.roll, m.pitch, m.yaw))
        return vector - x

    def loiter_to_ne(self, x, y, z, timeout=30):
        dest = rotmat.Vector3(x, y, z)
        tstart = self.get_sim_time()
        while True:
            if self.get_sim_time_cached() - tstart > timeout:
                raise NotAchievedException("Did not loiter to ne!")
            m_pos = self.mav.recv_match(type='LOCAL_POSITION_NED',
                                        blocking=True)
            pos = rotmat.Vector3(m_pos.x, m_pos.y, m_pos.z)
            delta_ef = pos - dest
            dist = math.sqrt(delta_ef.x * delta_ef.x + delta_ef.y * delta_ef.y)
            dist_max = 2
            self.progress("dist=%f want <%f" % (dist, dist_max))
            if dist < dist_max:
                break
            delta_bf = self.earth_to_body(delta_ef)
            angle_x = math.atan2(delta_bf.x, delta_bf.z)
            angle_y = math.atan2(delta_bf.y, delta_bf.z)
            distance = math.sqrt(delta_bf.x * delta_bf.x +
                                 delta_bf.y * delta_bf.y +
                                 delta_bf.z * delta_bf.z)
            self.mav.mav.landing_target_send(
                0, # time_usec
                1, # target_num
                mavutil.mavlink.MAV_FRAME_GLOBAL, # frame; AP ignores
                angle_x, # angle x (radians)
                angle_y, # angle y (radians)
                distance, # distance to target
                0.01, # size of target in radians, X-axis
                0.01 # size of target in radians, Y-axis
            )

        tstart = self.get_sim_time()
        while self.get_sim_time_cached() - tstart < 10:
            m_pos = self.mav.recv_match(type='LOCAL_POSITION_NED',
                                        blocking=True)
            pos = rotmat.Vector3(m_pos.x, m_pos.y, m_pos.z)
            delta_ef = pos - dest
            dist = math.sqrt(delta_ef.x * delta_ef.x + delta_ef.y * delta_ef.y)
            self.progress("dist=%f" % (dist,))

    def fly_payload_place_mission(self):
        """Test payload placing in auto."""
        self.context_push()

        ex = None
        try:
            self.set_parameter("RNGFND1_TYPE", 1)
            self.set_parameter("RNGFND1_MIN_CM", 0)
            self.set_parameter("RNGFND1_MAX_CM", 4000)
            self.set_parameter("RNGFND1_PIN", 0)
            self.set_parameter("RNGFND1_SCALING", 12.12)
            self.set_parameter("GRIP_ENABLE", 1)
            self.set_parameter("GRIP_TYPE", 1)
            self.set_parameter("SIM_GRPS_ENABLE", 1)
            self.set_parameter("SIM_GRPS_PIN", 8)
            self.set_parameter("SERVO8_FUNCTION", 28)
            self.set_parameter("RC9_OPTION", 19)
            self.reboot_sitl()
            self.set_rc(9, 2000)
            # load the mission:
            self.load_mission("copter_payload_place.txt")

            self.progress("Waiting for location")
            self.mav.location()
            self.zero_throttle()
            self.mavproxy.send('switch 6\n')  # stabilize mode
            self.wait_heartbeat()
            self.wait_mode('STABILIZE')
            self.wait_ready_to_arm()

            self.arm_vehicle()

            self.mavproxy.send('switch 4\n')  # auto mode
            self.wait_heartbeat()
            self.wait_mode('AUTO')

            self.set_rc(3, 1500)
            self.wait_text("Gripper load releas", timeout=90)

            self.mav.motors_disarmed_wait()

        except Exception as e:
            self.progress("Exception caught")
            ex = e

        self.context_pop()
        self.reboot_sitl()
        self.progress("All done")

        if ex is not None:
            raise ex

    def fly_guided_change_submode(self):
        """"Ensure we can move around in guided after a takeoff command."""

        '''start by disabling GCS failsafe, otherwise we immediately disarm
        due to (apparently) not receiving traffic from the GCS for
        too long.  This is probably a function of --speedup'''
        self.set_parameter("FS_GCS_ENABLE", 0)
        self.set_parameter("DISARM_DELAY", 0) # until traffic problems are fixed
        self.change_mode("GUIDED")
        self.wait_ready_to_arm()
        self.arm_vehicle()

        self.user_takeoff(alt_min=10)

        """yaw through absolute angles using MAV_CMD_CONDITION_YAW"""
        self.guided_achieve_heading(45)
        self.guided_achieve_heading(135)

        """move the vehicle using set_position_target_global_int"""
        self.fly_guided_move_global_relative_alt(5, 5, 10)

        """move the vehicle using MAVLINK_MSG_ID_SET_POSITION_TARGET_LOCAL_NED"""
        self.fly_guided_stop()
        self.fly_guided_move_local(5, 5, 10)

        """ Check target position received by vehicle using SET_MESSAGE_INTERVAL """
        self.test_guided_local_position_target(5, 5, 10)
        self.test_guided_local_velocity_target(2, 2, 1)
        self.test_position_target_message_mode()

        self.do_RTL()

    def test_gripper_mission(self):
        self.context_push()
        ex = None
        try:
            self.load_mission("copter-gripper-mission.txt")
            self.mavproxy.send('mode loiter\n')
            self.wait_ready_to_arm()
            self.arm_vehicle()
            self.mavproxy.send('mode auto\n')
            self.wait_mode('AUTO')
            self.set_rc(3, 1500)
            self.mavproxy.expect("Gripper Grabbed")
            self.mavproxy.expect("Gripper Released")
        except Exception as e:
            self.progress("Exception caught: %s" % str(e))
            self.mavproxy.send('mode land\n')
            ex = e
        self.context_pop()
        self.mav.motors_disarmed_wait()
        if ex is not None:
            raise ex

    def fly_manual_throttle_mode_change(self):
        self.set_parameter("FS_GCS_ENABLE", 0) # avoid GUIDED instant disarm
        self.change_mode("STABILIZE")
        self.wait_ready_to_arm()
        self.arm_vehicle()
        self.change_mode("ACRO")
        self.change_mode("STABILIZE")
        self.change_mode("GUIDED")
        self.set_rc(3, 1700)
        self.watch_altitude_maintained(-1, 0.2) # should not take off in guided
        self.run_cmd_do_set_mode(
            "ACRO",
            want_result=mavutil.mavlink.MAV_RESULT_UNSUPPORTED) # should fix this result code!
        self.run_cmd_do_set_mode(
            "STABILIZE",
            want_result=mavutil.mavlink.MAV_RESULT_UNSUPPORTED) # should fix this result code!
        self.run_cmd_do_set_mode(
            "DRIFT",
            want_result=mavutil.mavlink.MAV_RESULT_UNSUPPORTED) # should fix this result code!
        self.set_rc(3, 1000)
        self.run_cmd_do_set_mode("ACRO")
        self.mav.motors_disarmed_wait()

    def test_mount_pitch(self, despitch, despitch_tolerance, timeout=10):
        tstart = self.get_sim_time()
        while True:
            if self.get_sim_time_cached() - tstart > timeout:
                raise NotAchievedException("Mount pitch not achieved")

            m = self.mav.recv_match(type='MOUNT_STATUS',
                                    blocking=True,
                                    timeout=5)
#            self.progress("pitch=%f roll=%f yaw=%f" %
#                          (m.pointing_a, m.pointing_b, m.pointing_c))
            mount_pitch = m.pointing_a/100.0 # centidegrees to degrees
            if abs(despitch - mount_pitch) > despitch_tolerance:
                self.progress("Mount pitch incorrect: %f != %f" %
                              (mount_pitch, despitch))
                continue
            self.progress("Mount pitch correct: %f degrees == %f" %
                          (mount_pitch, despitch))
            return

    def do_pitch(self, pitch):
        '''pitch aircraft in guided/angle mode'''
        self.mav.mav.set_attitude_target_send(
            0, # time_boot_ms
            1, # target sysid
            1, # target compid
            0, # bitmask of things to ignore
            mavextra.euler_to_quat([0, math.radians(pitch), 0]), # att
            0, # roll rate (rad/s)
            1, # pitch rate
            0, # yaw rate
            0.5) # thrust, 0 to 1, translated to a climb/descent rate

    def test_mount(self):
        ex = None
        self.context_push()
        try:
            '''start by disabling GCS failsafe, otherwise we immediately disarm
            due to (apparently) not receiving traffic from the GCS for
            too long.  This is probably a function of --speedup'''
            self.set_parameter("FS_GCS_ENABLE", 0)

            self.progress("Setting up servo mount")
            roll_servo = 5
            pitch_servo = 6
            yaw_servo = 7
            self.set_parameter("MNT_TYPE", 1)
            self.set_parameter("SERVO%u_FUNCTION" % roll_servo, 8) # roll
            self.set_parameter("SERVO%u_FUNCTION" % pitch_servo, 7) # pitch
            self.set_parameter("SERVO%u_FUNCTION" % yaw_servo, 6) # yaw
            self.reboot_sitl() # to handle MNT_TYPE changing

            # make sure we're getting mount status and gimbal reports
            self.mav.recv_match(type='MOUNT_STATUS',
                                blocking=True,
                                timeout=5)
            self.mav.recv_match(type='GIMBAL_REPORT',
                                blocking=True,
                                timeout=5)

            # test pitch isn't stabilising:
            m = self.mav.recv_match(type='MOUNT_STATUS',
                                    blocking=True,
                                    timeout=5)
            if m.pointing_a != 0 or m.pointing_b != 0 or m.pointing_c != 0:
                raise NotAchievedException("Mount stabilising when not requested")

            self.mavproxy.send('mode guided\n')
            self.wait_mode('GUIDED')
            self.wait_ready_to_arm()
            self.arm_vehicle()

            self.user_takeoff()

            despitch = 10
            despitch_tolerance = 3

            self.progress("Pitching vehicle")
            self.do_pitch(despitch) # will time out!

            self.wait_pitch(despitch, despitch_tolerance)

            # check we haven't modified:
            m = self.mav.recv_match(type='MOUNT_STATUS',
                                    blocking=True,
                                    timeout=5)
            if m.pointing_a != 0 or m.pointing_b != 0 or m.pointing_c != 0:
                raise NotAchievedException("Mount stabilising when not requested")

            self.progress("Enable pitch stabilization using MOUNT_CONFIGURE")
            self.mav.mav.mount_configure_send(
                1, # target system
                1, # target component
                mavutil.mavlink.MAV_MOUNT_MODE_RC_TARGETING,
                0, # stab-roll
                1, # stab-pitch
                0)

            self.do_pitch(despitch)
            self.test_mount_pitch(-despitch, 1)

            self.progress("Disable pitch using MAV_CMD_DO_MOUNT_CONFIGURE")
            self.do_pitch(despitch)
            self.run_cmd(mavutil.mavlink.MAV_CMD_DO_MOUNT_CONFIGURE,
                         mavutil.mavlink.MAV_MOUNT_MODE_RC_TARGETING,
                         0,
                         0,
                         0,
                         0,
                         0,
                         0,
                         )
            self.test_mount_pitch(0, 0)

            self.progress("Point somewhere using MOUNT_CONTROL (ANGLE)")
            self.do_pitch(despitch)
            self.run_cmd(mavutil.mavlink.MAV_CMD_DO_MOUNT_CONFIGURE,
                         mavutil.mavlink.MAV_MOUNT_MODE_MAVLINK_TARGETING,
                         0,
                         0,
                         0,
                         0,
                         0,
                         0,
                         )
            self.mav.mav.mount_control_send(
                1, # target system
                1, # target component
                20 * 100, # pitch
                20 * 100, # roll (centidegrees)
                0,  # yaw
                0   # save position
            )
            self.test_mount_pitch(20, 1)

            self.progress("Point somewhere using MOUNT_CONTROL (GPS)")
            self.do_pitch(despitch)
            self.run_cmd(mavutil.mavlink.MAV_CMD_DO_MOUNT_CONFIGURE,
                         mavutil.mavlink.MAV_MOUNT_MODE_GPS_POINT,
                         0,
                         0,
                         0,
                         0,
                         0,
                         0,
                         )
            start = self.mav.location()
            self.progress("start=%s" % str(start))
            (t_lat, t_lon) = mavextra.gps_offset(start.lat, start.lng, 10, 20)
            t_alt = 0

            self.progress("loc %f %f %f" % (start.lat, start.lng, start.alt))
            self.progress("targetting %f %f %f" % (t_lat, t_lon, t_alt))
            self.do_pitch(despitch)
            self.mav.mav.mount_control_send(
                1, # target system
                1, # target component
                int(t_lat * 1e7), # lat
                int(t_lon * 1e7), # lon
                t_alt * 100, # alt
                0  # save position
            )
            self.test_mount_pitch(-52, 5)

            # now test RC targetting
            self.progress("Testing mount RC targetting")

            # this is a one-off; ArduCopter *will* time out this directive!
            self.progress("Levelling aircraft")
            self.mav.mav.set_attitude_target_send(
                0, # time_boot_ms
                1, # target sysid
                1, # target compid
                0, # bitmask of things to ignore
                mavextra.euler_to_quat([0, 0, 0]), # att
                1, # roll rate (rad/s)
                1, # pitch rate
                1, # yaw rate
                0.5) # thrust, 0 to 1, translated to a climb/descent rate

            self.run_cmd(mavutil.mavlink.MAV_CMD_DO_MOUNT_CONFIGURE,
                         mavutil.mavlink.MAV_MOUNT_MODE_RC_TARGETING,
                         0,
                         0,
                         0,
                         0,
                         0,
                         0,
                         )
            try:
                self.context_push()
                self.set_parameter('MNT_RC_IN_ROLL', 11)
                self.set_parameter('MNT_RC_IN_TILT', 12)
                self.set_parameter('MNT_RC_IN_PAN', 13)
                self.progress("Testing RC angular control")
                self.set_rc(11, 1500)
                self.set_rc(12, 1500)
                self.set_rc(13, 1500)
                self.test_mount_pitch(0, 1)
                self.set_rc(12, 1400)
                self.test_mount_pitch(-11.25, 0.01)
                self.set_rc(12, 1800)
                self.test_mount_pitch(33.75, 0.01)
                self.set_rc(11, 1500)
                self.set_rc(12, 1500)
                self.set_rc(13, 1500)

                self.progress("Testing RC rate control")
                self.set_parameter('MNT_JSTICK_SPD', 10)
                self.test_mount_pitch(0, 1)
                self.set_rc(12, 1300)
                self.test_mount_pitch(-5, 1)
                self.test_mount_pitch(-10, 1)
                self.test_mount_pitch(-15, 1)
                self.test_mount_pitch(-20, 1)
                self.set_rc(12, 1700)
                self.test_mount_pitch(-15, 1)
                self.test_mount_pitch(-10, 1)
                self.test_mount_pitch(-5, 1)
                self.test_mount_pitch(0, 1)
                self.test_mount_pitch(5, 1)

                self.progress("Reverting to angle mode")
                self.set_parameter('MNT_JSTICK_SPD', 0)
                self.set_rc(12, 1500)
                self.test_mount_pitch(0, 0.1)

                self.context_pop()

            except Exception:
                self.context_pop()
                raise

            self.progress("Testing mount ROI behaviour")
            self.test_mount_pitch(0, 0.1)
            start = self.mav.location()
            self.progress("start=%s" % str(start))
            (roi_lat, roi_lon) = mavextra.gps_offset(start.lat,
                                                     start.lng,
                                                     10,
                                                     20)
            roi_alt = 0
            self.progress("Using MAV_CMD_DO_SET_ROI_LOCATION")
            self.run_cmd(mavutil.mavlink.MAV_CMD_DO_SET_ROI_LOCATION,
                         0,
                         0,
                         0,
                         0,
                         roi_lat,
                         roi_lon,
                         roi_alt,
                         )
            self.test_mount_pitch(-52, 5)

            start = self.mav.location()
            (roi_lat, roi_lon) = mavextra.gps_offset(start.lat,
                                                     start.lng,
                                                     -100,
                                                     -200)
            roi_alt = 0
            self.progress("Using MAV_CMD_DO_SET_ROI")
            self.run_cmd(mavutil.mavlink.MAV_CMD_DO_SET_ROI,
                         0,
                         0,
                         0,
                         0,
                         roi_lat,
                         roi_lon,
                         roi_alt,
                         )
            self.test_mount_pitch(-7.5, 1)

            self.progress("checking ArduCopter yaw-aircraft-for-roi")
            try:
                self.context_push()

                m = self.mav.recv_match(type='VFR_HUD', blocking=True)
                self.progress("current heading %u" % m.heading)
                self.set_parameter("SERVO%u_FUNCTION" % yaw_servo, 0) # yaw
                self.progress("Waiting for check_servo_map to do its job")
                self.wait_seconds(5)
                start = self.mav.location()
                self.progress("Moving to guided/position controller")
                self.fly_guided_move_global_relative_alt(1, 0, 0)
                self.guided_achieve_heading(0)
                (roi_lat, roi_lon) = mavextra.gps_offset(start.lat,
                                                         start.lng,
                                                         -100,
                                                         -200)
                roi_alt = 0
                self.progress("Using MAV_CMD_DO_SET_ROI")
                self.run_cmd(mavutil.mavlink.MAV_CMD_DO_SET_ROI,
                             0,
                             0,
                             0,
                             0,
                             roi_lat,
                             roi_lon,
                             roi_alt,
                             )

                self.wait_heading(110, timeout=600)

                self.context_pop()
            except Exception:
                self.context_pop()
                raise

        except Exception as e:
            ex = e
        self.context_pop()

        self.disarm_vehicle(force=True)
        self.reboot_sitl() # to handle MNT_TYPE changing

        if ex is not None:
            raise ex

    def fly_throw_mode(self):
        # test boomerang mode:
        self.progress("Throwing vehicle away")
        self.set_parameter("THROW_NEXTMODE", 6)
        self.set_parameter("SIM_SHOVE_Z", -30)
        self.set_parameter("SIM_SHOVE_X", -20)
        self.change_mode('THROW')
        self.wait_ready_to_arm()
        self.arm_vehicle()
        try:
            self.set_parameter("SIM_SHOVE_TIME", 500)
        except ValueError as e:
            # the shove resets this to zero
            pass

        tstart = self.get_sim_time()
        self.wait_mode('RTL')
        max_good_tdelta = 15
        tdelta = self.get_sim_time() - tstart
        self.progress("Vehicle in RTL")
        self.mav.motors_disarmed_wait()
        self.progress("Vehicle disarmed")
        if tdelta > max_good_tdelta:
            raise NotAchievedException("Took too long to enter RTL: %fs > %fs" %
                                       (tdelta, max_good_tdelta))
        self.progress("Vehicle returned")

    def test_onboard_compass_calibration(self, timeout=240):
        twist_x = 2.1
        twist_y = 2.2
        twist_z = 2.3
        ex = None
        self.context_push()
        try:
            self.set_parameter("SIM_GND_BEHAV", 0)
            self.set_parameter("AHRS_EKF_TYPE", 10)
            self.reboot_sitl()

            report = self.mav.messages.get("MAG_CAL_REPORT", None)
            if report is not None:
                raise PreconditionFailedException("MAG_CAL_REPORT found")

            self.run_cmd(mavutil.mavlink.MAV_CMD_DO_START_MAG_CAL,
                         1, # bitmask of compasses to calibrate
                         0,
                         0,
                         0,
                         0,
                         0,
                         0,
                         timeout=1)
            tstart = self.get_sim_time()
            last_twist_time = 0
            while True:
                now = self.get_sim_time_cached()
                if now - tstart > timeout:
                    raise NotAchievedException("timeout before cal complete")
                report = self.mav.messages.get("MAG_CAL_REPORT", None)
                if report is not None:
                    print("Report: %s" % str(report))
                    break
                if now - last_twist_time > 5:
                    last_twist_time = now
                    twist_x *= 1.1
                    twist_y *= 1.2
                    twist_z *= 1.3
                    if abs(twist_x) > 10:
                        twist_x /= -2
                    if abs(twist_y) > 10:
                        twist_y /= -2
                    if abs(twist_z) > 10:
                        twist_z /= -2
                    self.set_parameter("SIM_TWIST_X", twist_x)
                    self.set_parameter("SIM_TWIST_Y", twist_y)
                    self.set_parameter("SIM_TWIST_Z", twist_z)
                    try:
                        self.set_parameter("SIM_TWIST_TIME", 100)
                    except ValueError as e:
                        # the shove resets this to zero
                        pass

                m = self.mav.recv_match(type="MAG_CAL_PROGRESS", timeout=1)
                self.progress("progress: %s" % str(m))
                if m is None:
                    continue
                att = self.mav.messages.get("ATTITUDE", None)
                self.progress("Attitude: %f %f %f" %
                              (math.degrees(att.roll), math.degrees(att.pitch), math.degrees(att.yaw)))
        except Exception as e:
            print("Exception caught: %s" % str(e))
            ex = e

        self.context_pop()
        self.reboot_sitl()
        if ex is not None:
            raise ex

    def fly_brake_mode(self):
        # test brake mode
        self.progress("Testing brake mode")
        self.takeoff(10, mode="LOITER")

        self.progress("Ensuring RC inputs have no effect in brake mode")
        self.change_mode("STABILIZE")
        self.set_rc(3, 1500)
        self.set_rc(2, 1200)
        self.wait_groundspeed(5, 1000)

        self.change_mode("BRAKE")
        self.wait_groundspeed(0, 1)

        self.set_rc(2, 1500)

        self.do_RTL()
        self.progress("Ran brake  mode")

    def fly_precision_companion(self):
        """Use Companion PrecLand backend precision messages to loiter."""

        self.context_push()

        ex = None
        try:
            self.set_parameter("PLND_ENABLED", 1)
            self.fetch_parameters()
            # enable companion backend:
            self.set_parameter("PLND_TYPE", 1)

            self.set_parameter("RNGFND1_TYPE", 1)
            self.set_parameter("RNGFND1_MIN_CM", 0)
            self.set_parameter("RNGFND1_MAX_CM", 4000)
            self.set_parameter("RNGFND1_PIN", 0)
            self.set_parameter("RNGFND1_SCALING", 12.12)

            # set up a channel switch to enable precision loiter:
            self.set_parameter("RC7_OPTION", 39)

            self.reboot_sitl()

            self.progress("Waiting for location")
            self.mav.location()
            self.zero_throttle()
            self.mavproxy.send('switch 6\n')  # stabilize mode
            self.wait_heartbeat()
            self.wait_mode('STABILIZE')
            self.wait_ready_to_arm()

            # we should be doing precision loiter at this point
            start = self.mav.recv_match(type='LOCAL_POSITION_NED',
                                        blocking=True)

            self.arm_vehicle()
            self.set_rc(3, 1800)
            alt_min = 10
            self.wait_altitude(alt_min,
                               (alt_min + 5),
                               relative=True)
            self.set_rc(3, 1500)
            # move away a little
            self.set_rc(2, 1550)
            self.wait_distance(5)
            self.set_rc(2, 1500)
            self.mavproxy.send('mode loiter\n')
            self.wait_mode('LOITER')

            # turn precision loiter on:
            self.set_rc(7, 2000)

            # try to drag aircraft to a position 5 metres north-east-east:
            self.loiter_to_ne(start.x + 5, start.y + 10, start.z + 10)
            self.loiter_to_ne(start.x + 5, start.y - 10, start.z + 10)

        except Exception as e:
            self.progress("Exception caught: %s" % self.get_exception_stacktrace(e))
            ex = e

        self.context_pop()
        self.zero_throttle()
        self.disarm_vehicle(force=True)
        self.reboot_sitl()
        self.progress("All done")

        if ex is not None:
            raise ex

    def loiter_requires_position(self):
        # ensure we can't switch to LOITER without position
        self.progress("Ensure we can't enter LOITER without position")
        self.context_push()
        self.set_parameter("GPS_TYPE", 0)
        self.reboot_sitl()
        self.change_mode('STABILIZE')
        self.wait_ekf_flags((mavutil.mavlink.ESTIMATOR_ATTITUDE |
                             mavutil.mavlink.ESTIMATOR_VELOCITY_VERT |
                             mavutil.mavlink.ESTIMATOR_POS_VERT_ABS |
                             mavutil.mavlink.ESTIMATOR_CONST_POS_MODE |
                             mavutil.mavlink.ESTIMATOR_PRED_POS_HORIZ_REL),
                            0,
                            timeout=120)
        self.arm_vehicle()
        self.mavproxy.send("mode LOITER\n")
        self.mavproxy.expect("requires position")
        self.disarm_vehicle()
        self.context_pop()
        self.reboot_sitl()

    def test_arm_feature(self):
        self.loiter_requires_position()

        super(AutoTestCopter, self).test_arm_feature()

    def test_parameter_checks(self):
        self.test_parameter_checks_poscontrol("PSC")

    def fly_poshold_takeoff(self):
        """ensure vehicle stays put until it is ready to fly"""
        self.context_push()

        ex = None
        try:
            self.set_parameter("PILOT_TKOFF_ALT", 700)
            self.mavproxy.send('mode POSHOLD\n')
            self.wait_mode('POSHOLD')
            self.set_rc(3, 1000)
            self.wait_ready_to_arm()
            self.arm_vehicle()
            self.wait_seconds(2)
            # check we are still on the ground...
            m = self.mav.recv_match(type='GLOBAL_POSITION_INT', blocking=True)
            if abs(m.relative_alt) > 100:
                raise NotAchievedException("Took off prematurely")

            self.progress("Pushing throttle up")
            self.set_rc(3, 1710)
            self.wait_seconds(0.5)
            self.progress("Bringing back to hover throttle")
            self.set_rc(3, 1500)

            # make sure we haven't already reached alt:
            m = self.mav.recv_match(type='GLOBAL_POSITION_INT', blocking=True)
            max_initial_alt = 500
            if abs(m.relative_alt) > max_initial_alt:
                raise NotAchievedException("Took off too fast (%f > %f" %
                                           (abs(m.relative_alt), max_initial_alt))

            self.progress("Monitoring takeoff-to-alt")
            self.wait_altitude(6.9, 8, relative=True)

            self.progress("Making sure we stop at our takeoff altitude")
            tstart = self.get_sim_time()
            while self.get_sim_time() - tstart < 5:
                m = self.mav.recv_match(type='GLOBAL_POSITION_INT', blocking=True)
                delta = abs(7000 - m.relative_alt)
                self.progress("alt=%f delta=%f" % (m.relative_alt/1000,
                                                   delta/1000))
                if delta > 1000:
                    raise NotAchievedException("Failed to maintain takeoff alt")
            self.progress("takeoff OK")
        except Exception as e:
            ex = e

        self.mavproxy.send('mode LAND\n')
        self.wait_mode('LAND')
        self.mav.motors_disarmed_wait()
        self.set_rc(8, 1000)

        self.context_pop()

        if ex is not None:
            raise ex

    def initial_mode(self):
        return "STABILIZE"

    def initial_mode_switch_mode(self):
        return "STABILIZE"

    def default_mode(self):
        return "STABILIZE"

    def rc_defaults(self):
        ret = super(AutoTestCopter, self).rc_defaults()
        ret[3] = 1000
        ret[5] = 1800 # mode switch
        return ret

    def test_manual_control(self):
        '''test manual_control mavlink message'''
        self.change_mode('STABILIZE')
        self.takeoff(10)

        tstart = self.get_sim_time_cached()
        want_pitch_degrees = -20
        while True:
            if self.get_sim_time_cached() - tstart > 10:
                raise AutoTestTimeoutException("Did not reach pitch")
            self.progress("Sending pitch-forward")
            self.mav.mav.manual_control_send(
                1, # target system
                500, # x (pitch)
                32767, # y (roll)
                32767, # z (thrust)
                32767, # r (yaw)
                0) # button mask
            m = self.mav.recv_match(type='ATTITUDE', blocking=True, timeout=1)
            print("m=%s" % str(m))
            if m is None:
                continue
            p = math.degrees(m.pitch)
            self.progress("pitch=%f want<=%f" % (p, want_pitch_degrees))
            if p <= want_pitch_degrees:
                break
        self.mav.mav.manual_control_send(
            1, # target system
            32767, # x (pitch)
            32767, # y (roll)
            32767, # z (thrust)
            32767, # r (yaw)
            0) # button mask
        self.do_RTL()

    def tests(self):
        '''return list of all tests'''
        ret = super(AutoTestCopter, self).tests()
        ret.extend([

            ("NavDelayTakeoffAbsTime",
             "Fly Nav Delay (takeoff)",
             self.fly_nav_takeoff_delay_abstime),

            ("NavDelayAbsTime",
             "Fly Nav Delay (AbsTime)",
             self.fly_nav_delay_abstime),

            ("NavDelay",
             "Fly Nav Delay",
             self.fly_nav_delay),

            ("GuidedSubModeChange",
             "Test submode change",
             self.fly_guided_change_submode),

            ("LoiterToAlt",
             "Loiter-To-Alt",
             self.fly_loiter_to_alt),

            ("PayLoadPlaceMission",
             "Payload Place Mission",
             self.fly_payload_place_mission),

            ("PrecisionLoiterCompanion",
             "Precision Loiter (Companion)",
             self.fly_precision_companion),

            ("PrecisionLandingSITL",
             "Precision Landing (SITL)",
             self.fly_precision_sitl),

            ("SetModesViaModeSwitch",
             "Set modes via modeswitch",
             self.test_setting_modes_via_modeswitch),

            ("SetModesViaAuxSwitch",
             "Set modes via auxswitch",
             self.test_setting_modes_via_auxswitch),

            ("AutoTune", "Fly AUTOTUNE mode", self.fly_autotune),

            ("ThrowMode", "Fly Throw Mode", self.fly_throw_mode),

            ("BrakeMode", "Fly Brake Mode", self.fly_brake_mode),

            ("RecordThenPlayMission",
             "Use switches to toggle in mission, then fly it",
             self.fly_square),

            ("ThrottleFailsafe",
             "Test Throttle Failsafe",
             self.fly_throttle_failsafe),

            ("BatteryFailsafe",
             "Fly Battery Failsafe",
             self.fly_battery_failsafe),

            ("StabilityPatch",
             "Fly stability patch",
             lambda: self.fly_stability_patch(30)),

            ("HorizontalFence",
             "Test horizontal fence",
             self.fly_fence_test),

            ("MaxAltFence",
             "Test Max Alt Fence",
             self.fly_alt_max_fence_test),

            ("GPSGlitchLoiter",
             "GPS Glitch Loiter Test",
             self.fly_gps_glitch_loiter_test),

            ("GPSGlitchAuto",
             "GPS Glitch Auto Test",
             self.fly_gps_glitch_auto_test),

            ("ModeAltHold",
             "Test AltHold Mode",
             self.test_mode_ALT_HOLD),

            ("ModeLoiter",
             "Test Loiter Mode",
             self.loiter),

            ("SimpleMode",
             "Fly in SIMPLE mode",
             self.fly_simple),

            ("SuperSimpleCircle",
             "Fly a circle in SUPER SIMPLE mode",
             self.fly_super_simple),

            ("ModeCircle",
             "Fly CIRCLE mode",
             self.fly_circle),

            ("OpticalFlowLimits",
             "Fly Optical Flow limits",
             self.fly_optical_flow_limits),

            ("MotorFail",
             "Fly motor failure test",
             self.fly_motor_fail),

            ("Flip",
             "Fly Flip Mode",
             self.fly_flip),

            ("CopterMission",
             "Fly copter mission",
             self.fly_auto_test),

            # Gripper test
            ("Gripper",
             "Test gripper",
             self.test_gripper),

            ("TestGripperMission",
             "Test Gripper mission items",
             self.test_gripper_mission),

            ("VisionPosition",
             "Fly Vision Position",
             self.fly_vision_position),

            ("RTLSpeed",
             "Fly RTL Speed",
             self.fly_rtl_speed),

            ("Mount",
             "Test Camera/Antenna Mount",
             self.test_mount),

            ("RangeFinder",
             "Test RangeFinder Basic Functionality",
             self.test_rangefinder),

            ("Parachute",
             "Test Parachute Functionality",
             self.test_parachute),

            ("ParameterChecks",
             "Test Arming Parameter Checks",
             self.test_parameter_checks),

            ("ManualThrottleModeChange",
             "Check manual throttle mode changes denied on high throttle",
             self.fly_manual_throttle_mode_change),

            ("MANUAL_CONTROL",
             "Test mavlink MANUAL_CONTROL",
             self.test_manual_control),

            # Zigzag mode test
            ("ZigZag", "Fly ZigZag Mode", self.fly_zigzag_mode),

            ("PosHoldTakeOff",
             "Fly POSHOLD takeoff",
             self.fly_poshold_takeoff),

            ("OnboardCompassCalibration",
             "Test onboard compass calibration",
             self.test_onboard_compass_calibration),

            ("LogDownLoad",
             "Log download",
             lambda: self.log_download(
                 self.buildlogs_path("ArduCopter-log.bin"),
                 upload_logs=len(self.fail_list) > 0))
        ])
        return ret

    def disabled_tests(self):
        return {
            "Parachute": "See https://github.com/ArduPilot/ardupilot/issues/4702",
        }

class AutoTestHeli(AutoTestCopter):

    def log_name(self):
        return "HeliCopter"

    def default_frame(self):
        return "heli"

    def sitl_start_location(self):
        return SITL_START_LOCATION_AVC

    def is_heli(self):
        return True

    def rc_defaults(self):
        ret = super(AutoTestHeli, self).rc_defaults()
        ret[8] = 1000
        ret[3] = 1000 # collective
        return ret

    def loiter_requires_position(self):
        self.progress("Skipping loiter-requires-position for heli; rotor runup issues")

    # fly_avc_test - fly AVC mission
    def fly_avc_test(self):
        # Arm
        self.mavproxy.send('switch 6\n')  # stabilize mode
        self.wait_mode('STABILIZE')
        self.wait_ready_to_arm()

        self.arm_vehicle()
        self.progress("Raising rotor speed")
        self.set_rc(8, 2000)

        # upload mission from file
        self.progress("# Load copter_AVC2013_mission")
        # load the waypoint count
        num_wp = self.load_mission("copter_AVC2013_mission.txt")
        if not num_wp:
            raise NotAchievedException("load copter_AVC2013_mission failed")

        self.progress("Fly AVC mission from 1 to %u" % num_wp)
        self.mavproxy.send('wp set 1\n')

        # wait for motor runup
        self.wait_seconds(20)

        # switch into AUTO mode and raise throttle
        self.mavproxy.send('switch 4\n')  # auto mode
        self.wait_mode('AUTO')
        self.set_rc(3, 1500)

        # fly the mission
        self.wait_waypoint(0, num_wp-1, timeout=500)

        # set throttle to minimum
        self.zero_throttle()

        # wait for disarm
        self.mav.motors_disarmed_wait()
        self.progress("MOTORS DISARMED OK")

        self.progress("Lowering rotor speed")
        self.set_rc(8, 1000)

        self.progress("AVC mission completed: passed!")

    def fly_heli_poshold_takeoff(self):
        """ensure vehicle stays put until it is ready to fly"""
        self.context_push()

        ex = None
        try:
            self.set_parameter("PILOT_TKOFF_ALT", 700)
            self.mavproxy.send('mode POSHOLD\n')
            self.wait_mode('POSHOLD')
            self.set_rc(3, 1000)
            self.set_rc(8, 1000)
            self.wait_ready_to_arm()
            self.arm_vehicle()
            self.set_rc(8, 2000)
            self.progress("wait for rotor runup to complete")
            self.wait_servo_channel_value(8, 1900, timeout=10)
            self.wait_seconds(20)
            # check we are still on the ground...
            m = self.mav.recv_match(type='GLOBAL_POSITION_INT', blocking=True)
            if abs(m.relative_alt) > 100:
                raise NotAchievedException("Took off prematurely")
            self.progress("Pushing throttle past half-way")
            self.set_rc(3, 1600)
            self.wait_seconds(0.5)
            self.progress("Bringing back to hover throttle")
            self.set_rc(3, 1500)

            # make sure we haven't already reached alt:
            m = self.mav.recv_match(type='GLOBAL_POSITION_INT', blocking=True)
            if abs(m.relative_alt) > 500:
                raise NotAchievedException("Took off too fast")

            self.progress("Monitoring takeoff-to-alt")
            self.wait_altitude(6.9, 8, relative=True)

            self.progress("Making sure we stop at our takeoff altitude")
            tstart = self.get_sim_time()
            while self.get_sim_time() - tstart < 5:
                m = self.mav.recv_match(type='GLOBAL_POSITION_INT', blocking=True)
                delta = abs(7000 - m.relative_alt)
                self.progress("alt=%f delta=%f" % (m.relative_alt/1000,
                                                   delta/1000))
                if delta > 1000:
                    raise NotAchievedException("Failed to maintain takeoff alt")
            self.progress("takeoff OK")
        except Exception as e:
            ex = e

        self.mavproxy.send('mode LAND\n')
        self.wait_mode('LAND')
        self.mav.motors_disarmed_wait()
        self.set_rc(8, 1000)

        self.context_pop()

        if ex is not None:
            raise ex

    def fly_spline_waypoint(self):
        """ensure basic spline functionality works"""
        self.load_mission("copter_spline_mission.txt")
        self.change_mode("LOITER")
        self.wait_ready_to_arm()
        self.arm_vehicle()
        self.progress("Raising rotor speed")
        self.set_rc(8, 2000)
        self.wait_seconds(20)
        self.change_mode("AUTO")
        self.set_rc(3, 1500)
        tstart = self.get_sim_time()
        while True:
            if not self.armed():
                break
            remaining = self.get_sim_time() - tstart
            if remaining <= 0:
                raise AutoTestTimeoutException("Vehicle did not disarm after mission")
            self.delay_sim_time(1)
        self.progress("Lowering rotor speed")
        self.set_rc(8, 1000)

    def set_rc_default(self):
        super(AutoTestCopter, self).set_rc_default()
        self.progress("Lowering rotor speed")
        self.set_rc(8, 1000)

    def tests(self):
        '''return list of all tests'''
        ret = super(AutoTestCopter, self).tests()
        ret.extend([
            ("AVCMission", "Fly AVC mission", self.fly_avc_test),

            ("PosHoldTakeOff",
             "Fly POSHOLD takeoff",
             self.fly_heli_poshold_takeoff),

            ("SplineWaypoint",
             "Fly Spline Waypoints",
             self.fly_spline_waypoint),

            ("LogDownLoad",
             "Log download",
             lambda: self.log_download(
                 self.buildlogs_path("ArduCopter-log.bin"),
                 upload_logs=len(self.fail_list) > 0))
        ])
        return ret