VTOL control back transition ramp up time

src/modules/vtol_att_control/standard.cpp

@@ -64,6 +64,7 @@ Standard::Standard(VtolAttitudeControl *attc) :
 
 	_params_handles_standard.front_trans_dur = param_find("VT_F_TRANS_DUR");
 	_params_handles_standard.back_trans_dur = param_find("VT_B_TRANS_DUR");
+	_params_handles_standard.back_trans_ramp = param_find("VT_B_TRANS_RAMP");
 	_params_handles_standard.pusher_trans = param_find("VT_TRANS_THR");
 	_params_handles_standard.airspeed_blend = param_find("VT_ARSP_BLEND");
 	_params_handles_standard.airspeed_trans = param_find("VT_ARSP_TRANS");
@@ -97,6 +98,10 @@ Standard::parameters_update()
 	param_get(_params_handles_standard.back_trans_dur, &v);
 	_params_standard.back_trans_dur = math::constrain(v, 0.0f, 20.0f);
 
+	/* MC ramp up during back transition to mc mode */
+	param_get(_params_handles_standard.back_trans_ramp, &v);
+	_params_standard.back_trans_ramp = math::constrain(v, 0.0f, _params_standard.back_trans_dur);
+
 	/* target throttle value for pusher motor during the transition to fw mode */
 	param_get(_params_handles_standard.pusher_trans, &v);
 	_params_standard.pusher_trans = math::constrain(v, 0.0f, 5.0f);
@@ -355,9 +360,9 @@ void Standard::update_transition_state()
 		}
 
 		// continually increase mc attitude control as we transition back to mc mode
-		if (_params_standard.back_trans_dur > FLT_EPSILON) {
+		if (_params_standard.back_trans_ramp > FLT_EPSILON) {
 			float weight = (float)hrt_elapsed_time(&_vtol_schedule.transition_start) /
-				       ((_params_standard.back_trans_dur / 2) * 1000000.0f);
+				       ((_params_standard.back_trans_ramp) * 1000000.0f);
 			weight = math::constrain(weight, 0.0f, 1.0f);
 			_mc_roll_weight = weight;
 			_mc_pitch_weight = weight;

src/modules/vtol_att_control/standard.h

@@ -69,6 +69,7 @@ private:
 	struct {
 		float front_trans_dur;
 		float back_trans_dur;
+		float back_trans_ramp;
 		float pusher_trans;
 		float airspeed_blend;
 		float airspeed_trans;
@@ -86,6 +87,7 @@ private:
 	struct {
 		param_t front_trans_dur;
 		param_t back_trans_dur;
+		param_t back_trans_ramp;
 		param_t pusher_trans;
 		param_t airspeed_blend;
 		param_t airspeed_trans;

src/modules/vtol_att_control/standard_params.c

@@ -72,3 +72,15 @@ PARAM_DEFINE_FLOAT(VT_DWN_PITCH_MAX, 5.0f);
  * @group VTOL Attitude Control
  */
 PARAM_DEFINE_FLOAT(VT_FWD_THRUST_SC, 0.0f);
+
+/**
+ * Back transition MC motor ramp up time
+ *
+ * This sets the duration during wich the MC motors ramp up to the commanded thrust during the back transition stage.
+ *
+ * @unit s
+ * @min 0.0
+ * @max 20.0
+ * @group VTOL Attitude Control
+ */
+PARAM_DEFINE_FLOAT(VT_B_TRANS_RAMP, 3.0f);