urx is a python library to control the robots from Universal Robots. It is published under the LGPL license and comes with absolutely no guarantee.
It is meant as an easy to use module for pick and place operations, although it has been used for welding and other sensor based applications that do not require high control frequency.
Both the 'secondary port' interface and the real-time/matlab interface of the UR controller are used. urx can optionally use the python-math3d(GPL) library to receive and send transformation matrices to the robot urx is known to work with all release robots from Universal Robot.
The easiest is probably to use pip:
pip install urx
import urx rob = urx.Robot("192.168.0.100") rob.set_tcp((0, 0, 0.1, 0, 0, 0)) rob.set_payload(2, (0, 0, 0.1)) sleep(0.2) #leave some time to robot to process the setup commands rob.movej((1, 2, 3, 4, 5, 6), a, v) rob.movel((x, y, z, rx, ry, rz), a, v) print "Current tool pose is: ", rob.getl() rob.movel((0.1, 0, 0, 0, 0, 0), a, v, relative=true) # move relative to current pose rob.translate((0.1, 0, 0), a, v) #move tool and keep orientation rob.stopj(a) robot.movel(x, y, z, rx, ry, rz), wait=False) while True : sleep(0.1) #sleep first since the robot may not have processed the command yet if robot.is_program_running(): break robot.movel(x, y, z, rx, ry, rz), wait=False) while.robot.getForce() < 50: sleep(0.01) if not robot.is_program_running(): break robot.stopl() try: robot.movel((0,0,0.1,0,0,0), relative=True) except RobotError, ex: print("Robot could not execute move (emergency stop for example), do something", ex)
Development using Transform objects from math3d library:
from urx import Robot import math3d as m3d robot = Robot("192.168.1.1") mytcp = m3d.Transform() # create a matrix for our tool tcp mytcp.pos.z = 0.18 mytcp.orient.rotate_zb(pi/3) robot.set_tcp(mytcp) time.sleep(0.2) # get current pose, transform it and move robot to new pose trans = robot.get_pose() # get current transformation matrix (tool to base) trans.pos.z += 0.3 trans.orient.rotate_yb(pi/2) robot.set_pose(trans, acc=0.5, vel=0.2) # apply the new pose #or only work with orientation part o = robot.get_orientation() o.rotate_yb(pi) robot.set_orientation(o)
Other interactive methods/properties
from urx import Robot rob = Robot("192.168.1.1") rob.x # returns current x rob.rx # returns 0 (could return x component of axis vector, but it is not very usefull rob.rx -= 0.1 # rotate tool around X axis rob.z_t += 0.01 # move robot in tool z axis for +1cm csys = rob.new_csys_from_xpy() # generate a new csys from 3 points: X, origin, Y rob.set_csys(csys)
urx can also control a Robotiq gripper attached to the UR robot. The robotiq class was primarily developed by Mark Silliman.
import sys import urx from urx.robotiq_two_finger_gripper import Robotiq_Two_Finger_Gripper if __name__ == '__main__': rob = urx.Robot("192.168.0.100") robotiqgrip = Robotiq_Two_Finger_Gripper() if(len(sys.argv) != 2): print "false" sys.exit() if(sys.argv == "close") : robotiqgrip.close_gripper() if(sys.argv == "open") : robotiqgrip.open_gripper() rob.send_program(robotiqgrip.ret_program_to_run()) rob.close() print "true" sys.exit()