Copter: fixed RC failsafe handling for no RC receiver

ArduCopter/Attitude.cpp

@@ -4,6 +4,10 @@
 // returns desired yaw rate in centi-degrees per second
 float Copter::get_pilot_desired_yaw_rate(int16_t stick_angle)
 {
+    // throttle failsafe check
+    if (failsafe.radio || !ap.rc_receiver_present) {
+        return 0.0f;
+    }
     float yaw_request;
 
     // calculate yaw rate request
@@ -75,7 +79,7 @@ void Copter::set_throttle_takeoff()
 float Copter::get_pilot_desired_climb_rate(float throttle_control)
 {
     // throttle failsafe check
-    if (failsafe.radio) {
+    if (failsafe.radio || !ap.rc_receiver_present) {
         return 0.0f;
     }
 

ArduCopter/mode.cpp

@@ -351,6 +351,12 @@ void Mode::update_navigation()
 // returns desired angle in centi-degrees
 void Mode::get_pilot_desired_lean_angles(float &roll_out, float &pitch_out, float angle_max, float angle_limit) const
 {
+    // throttle failsafe check
+    if (copter.failsafe.radio || !copter.ap.rc_receiver_present) {
+        roll_out = 0;
+        pitch_out = 0;
+        return;
+    }
     // fetch roll and pitch inputs
     roll_out = channel_roll->get_control_in();
     pitch_out = channel_pitch->get_control_in();

ArduCopter/radio.cpp

@@ -94,11 +94,8 @@ void Copter::read_radio()
         set_throttle_and_failsafe(channel_throttle->get_radio_in());
         set_throttle_zero_flag(channel_throttle->get_control_in());
 
-        if (!ap.rc_receiver_present) {
-            // RC receiver must be attached if we've just got input and
-            // there are no overrides
-            ap.rc_receiver_present = !RC_Channels::has_active_overrides();
-        }
+        // RC receiver must be attached if we've just got input
+        ap.rc_receiver_present = true;
 
         // pass pilot input through to motors (used to allow wiggling servos while disarmed on heli, single, coax copters)
         radio_passthrough_to_motors();