AP_Motors: Rename and move Throttle Mix / Comp

libraries/AP_Motors/AP_MotorsMatrix.cpp

@@ -240,7 +240,7 @@ void AP_MotorsMatrix::output_armed_stabilizing()
     //      We will choose #1 (the best throttle for yaw control) if that means reducing throttle to the motors (i.e. we favour reducing throttle *because* it provides better yaw control)
     //      We will choose #2 (a mix of pilot and hover throttle) only when the throttle is quite low.  We favour reducing throttle instead of better yaw control because the pilot has commanded it
     int16_t motor_mid = (rpy_low+rpy_high)/2;
-    out_best_thr_pwm = min(out_mid_pwm - motor_mid, max(_rc_throttle.radio_out, _rc_throttle.radio_out*max(0,1.0f-_throttle_low_comp)+get_hover_throttle_as_pwm()*_throttle_low_comp));
+    out_best_thr_pwm = min(out_mid_pwm - motor_mid, max(_rc_throttle.radio_out, _rc_throttle.radio_out*max(0,1.0f-_throttle_thr_mix)+get_hover_throttle_as_pwm()*_throttle_thr_mix));
 
     // calculate amount of yaw we can fit into the throttle range
     // this is always equal to or less than the requested yaw from the pilot or rate controller

libraries/AP_Motors/AP_Motors_Class.cpp

@@ -93,6 +93,13 @@ const AP_Param::GroupInfo AP_Motors::var_info[] PROGMEM = {
     // @User: Advanced
     AP_GROUPINFO("CURR_MAX", 12, AP_Motors, _batt_current_max, AP_MOTORS_CURR_MAX_DEFAULT),
 
+    // @Param: THR_MIX_MIN
+    // @DisplayName: Throttle Mix Minimum
+    // @Description: Minimum ratio that the average throttle can increase above the desired throttle after roll, pitch and yaw are mixed
+    // @Range: 0.1 0.25
+    // @User: Advanced
+    AP_GROUPINFO("THR_MIX_MIN", 13, AP_Motors, _thr_mix_min, AP_MOTORS_THR_MIX_MIN_DEFAULT),
+
     AP_GROUPEND
 };
 
@@ -108,8 +115,8 @@ AP_Motors::AP_Motors(RC_Channel& rc_roll, RC_Channel& rc_pitch, RC_Channel& rc_t
     _max_throttle(AP_MOTORS_DEFAULT_MAX_THROTTLE),
     _hover_out(AP_MOTORS_DEFAULT_MID_THROTTLE),
     _spin_when_armed_ramped(0),
-    _throttle_low_comp(AP_MOTORS_THR_LOW_CMP_DEFAULT),
-    _throttle_low_comp_desired(AP_MOTORS_THR_LOW_CMP_DEFAULT),
+    _throttle_thr_mix(AP_MOTORS_THR_LOW_CMP_DEFAULT),
+    _throttle_thr_mix_desired(AP_MOTORS_THR_LOW_CMP_DEFAULT),
     _batt_voltage(0.0f),
     _batt_voltage_resting(0.0f),
     _batt_current(0.0f),
@@ -187,7 +194,7 @@ void AP_Motors::output()
     update_lift_max_from_batt_voltage();
 
     // move throttle_low_comp towards desired throttle low comp
-    update_throttle_low_comp();
+    update_throttle_thr_mix();
 
     if (_flags.armed) {
         if (!_flags.interlock) {
@@ -354,18 +361,18 @@ void AP_Motors::update_battery_resistance()
     }
 }
 
-// update_throttle_low_comp - slew set_throttle_low_comp to requested value
-void AP_Motors::update_throttle_low_comp()
+// update_throttle_thr_mix - slew set_throttle_thr_mix to requested value
+void AP_Motors::update_throttle_thr_mix()
 {
-    // slew _throttle_low_comp to _throttle_low_comp_desired
-    if (_throttle_low_comp < _throttle_low_comp_desired) {
+    // slew _throttle_thr_mix to _throttle_thr_mix_desired
+    if (_throttle_thr_mix < _throttle_thr_mix_desired) {
         // increase quickly (i.e. from 0.1 to 0.9 in 0.4 seconds)
-        _throttle_low_comp += min(2.0f/_loop_rate, _throttle_low_comp_desired-_throttle_low_comp);
-    } else if (_throttle_low_comp > _throttle_low_comp_desired) {
+        _throttle_thr_mix += min(2.0f/_loop_rate, _throttle_thr_mix_desired-_throttle_thr_mix);
+    } else if (_throttle_thr_mix > _throttle_thr_mix_desired) {
         // reduce more slowly (from 0.9 to 0.1 in 1.6 seconds)
-        _throttle_low_comp -= min(0.5f/_loop_rate, _throttle_low_comp-_throttle_low_comp_desired);
+        _throttle_thr_mix -= min(0.5f/_loop_rate, _throttle_thr_mix-_throttle_thr_mix_desired);
     }
-    _throttle_low_comp = constrain_float(_throttle_low_comp, 0.1f, 1.0f);
+    _throttle_thr_mix = constrain_float(_throttle_thr_mix, 0.1f, 1.0f);
 }
 
 float AP_Motors::get_compensation_gain() const

libraries/AP_Motors/AP_Motors_Class.h

@@ -63,6 +63,9 @@
 #define AP_MOTORS_THST_BAT_MIN_DEFAULT  0.0f
 #define AP_MOTORS_CURR_MAX_DEFAULT      0.0f    // current limiting max default
 #define AP_MOTORS_BATT_VOLT_FILT_HZ     0.5f    // battery voltage filtered at 0.5hz
+#define AP_MOTORS_THR_MIX_MIN_DEFAULT   0.1f    // minimum throttle mix
+#define AP_MOTORS_THR_MIX_MID_DEFAULT   0.5f    // manual throttle mix
+#define AP_MOTORS_THR_MIX_MAX_DEFAULT   0.9f    // maximum throttle mix
 
 // bit mask for recording which limits we have reached when outputting to motors
 #define AP_MOTOR_NO_LIMITS_REACHED  0x00
@@ -165,13 +168,15 @@ public:
     // set_density_ratio - sets air density as a proportion of sea level density
     void                set_air_density_ratio(float ratio) { _air_density_ratio = ratio; }
 
-    // set_throttle_low_comp - set desired throttle_low_comp (actual throttle_low_comp is slewed towards this value over 1~2 seconds)
+    // set_throttle_thr_mix - set desired throttle_thr_mix (actual throttle_thr_mix is slewed towards this value over 1~2 seconds)
     //  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
-    void                set_throttle_low_comp(float throttle_low_comp) { _throttle_low_comp_desired = throttle_low_comp; }
+    void                set_throttle_mix_min() { _throttle_thr_mix_desired = _thr_mix_min; }
+    void                set_throttle_mix_mid() { _throttle_thr_mix_desired = AP_MOTORS_THR_MIX_MID_DEFAULT; }
+    void                set_throttle_mix_max() { _throttle_thr_mix_desired = AP_MOTORS_THR_MIX_MAX_DEFAULT; }
 
-    // get_throttle_low_comp - get low throttle compensation value
-    float               get_throttle_low_comp() { return _throttle_low_comp; }
+    // get_throttle_thr_mix - get low throttle compensation value
+    float               is_throttle_mix_min() { return (_throttle_thr_mix < 1.25f*_thr_mix_min); }
 
     // get_lift_max - get maximum lift ratio
     float               get_lift_max() { return _lift_max; }
@@ -235,8 +240,8 @@ protected:
     // update_battery_resistance - calculate battery resistance when throttle is above hover_out
     void                update_battery_resistance();
 
-    // update_throttle_low_comp - updates thr_low_comp value towards the target
-    void                update_throttle_low_comp();
+    // update_throttle_thr_mix - updates thr_low_comp value towards the target
+    void                update_throttle_thr_mix();
 
     // return gain scheduling gain based on voltage and air density
     float               get_compensation_gain() const;
@@ -266,6 +271,7 @@ protected:
     AP_Float            _batt_voltage_max;      // maximum voltage used to scale lift
     AP_Float            _batt_voltage_min;      // minimum voltage used to scale lift
     AP_Float            _batt_current_max;      // current over which maximum throttle is limited
+    AP_Float            _thr_mix_min;           // current over which maximum throttle is limited
 
     // internal variables
     RC_Channel&         _rc_roll;               // roll input in from users is held in servo_out
@@ -278,8 +284,8 @@ protected:
     int16_t             _max_throttle;          // the maximum throttle to be sent to the motors (sometimes limited by slow start)
     int16_t             _hover_out;             // the estimated hover throttle as pct * 10 (i.e. 0 ~ 1000)
     int16_t             _spin_when_armed_ramped;// equal to _spin_when_armed parameter but slowly ramped up from zero
-    float               _throttle_low_comp;     // mix between throttle and hover throttle for 0 to 1 and ratio above hover throttle for >1
-    float               _throttle_low_comp_desired; // desired throttle_low_comp value, actual throttle_low_comp is slewed towards this value over 1~2 seconds
+    float               _throttle_thr_mix;      // mix between throttle and hover throttle for 0 to 1 and ratio above hover throttle for >1
+    float               _throttle_thr_mix_desired; // desired throttle_low_comp value, actual throttle_low_comp is slewed towards this value over 1~2 seconds
 
     // battery voltage compensation variables
     float               _batt_voltage;          // latest battery voltage reading