Copter: Add additional check to Throttle Mix/Comp

ArduCopter/ArduCopter.pde

@@ -919,7 +919,7 @@ static void throttle_loop()
     read_inertial_altitude();
 
     // update throttle_low_comp value (controls priority of throttle vs attitude control)
-    update_throttle_low_comp();
+    update_throttle_thr_mix();
 
     // check auto_armed status
     update_auto_armed();

ArduCopter/land_detector.pde

@@ -22,7 +22,7 @@ static void update_land_detector()
     // input throttle :                     in slow land the input throttle may be only slightly less than hover
 
     // check that the average throttle output is near minimum (less than 12.5% hover throttle)
-    bool motor_at_lower_limit = motors.limit.throttle_lower && (motors.get_throttle_low_comp() < 0.125f);
+    bool motor_at_lower_limit = motors.limit.throttle_lower && motors.is_throttle_mix_min();
     Vector3f accel_ef = ahrs.get_accel_ef_blended();
     accel_ef.z += GRAVITY_MSS;
 
@@ -55,39 +55,41 @@ static void update_land_detector()
     set_land_complete_maybe(land_detector >= LAND_DETECTOR_MAYBE_TRIGGER_SEC*MAIN_LOOP_RATE);
 }
 
-// update_throttle_low_comp - sets motors throttle_low_comp value depending upon vehicle state
+// update_throttle_thr_mix - sets motors throttle_low_comp value depending upon vehicle state
 //  low values favour pilot/autopilot throttle over attitude control, high values favour attitude control over throttle
 //  has no effect when throttle is above hover throttle
-static void update_throttle_low_comp()
+static void update_throttle_thr_mix()
 {
     if (mode_has_manual_throttle(control_mode)) {
         // manual throttle
         if(!motors.armed() || g.rc_3.control_in <= 0) {
-            motors.set_throttle_low_comp(0.1f);
+            motors.set_throttle_mix_min();
         } else {
-            motors.set_throttle_low_comp(0.5f);
+            motors.set_throttle_mix_mid();
         }
     } else {
         // autopilot controlled throttle
 
-        // check for aggressive flight requests
+        // check for aggressive flight requests - requested roll or pitch angle below 15 degrees
         const Vector3f angle_target = attitude_control.angle_ef_targets();
         bool large_angle_request = (pythagorous2(angle_target.x, angle_target.y) > 1500.0f);
 
-        // check for large external disturbance
+        // check for large external disturbance - angle error over 30 degrees
         const Vector3f angle_error = attitude_control.angle_bf_error();
         bool large_angle_error = (pythagorous2(angle_error.x, angle_error.y) > 3000.0f);
 
-        // check for large acceleration ( falling )
+        // check for large acceleration - falling or high turbulence
         Vector3f accel_ef = ahrs.get_accel_ef_blended();
         accel_ef.z += GRAVITY_MSS;
         bool accel_moving = (accel_ef.length() > 3.0f);
 
-        if ( large_angle_request || large_angle_error || accel_moving) {
+        // check for requested decent
-            // if target lean angle is over 15 degrees set high
+        bool descent_not_demanded = pos_control.get_desired_velocity().z >= 0.0f;
-            motors.set_throttle_low_comp(0.9f);
+
+        if ( large_angle_request || large_angle_error || accel_moving || descent_not_demanded) {
+            motors.set_throttle_mix_max();
         } else {
-            motors.set_throttle_low_comp(0.1f);
+            motors.set_throttle_mix_min();
         }
     }
 }