Copter: allow CH6 tuning of sonar gain

ArduCopter/ArduCopter.pde

@@ -2286,6 +2286,11 @@ static void tuning(){
         // set circle rate
         g.circle_rate.set(g.rc_6.control_in/25-20);     // allow approximately 45 degree turn rate in either direction
         break;
+
+    case CH6_SONAR_GAIN:
+        // set sonar gain
+        g.sonar_gain.set(tuning_value);
+        break;
     }
 }
 

ArduCopter/Parameters.pde

@@ -385,7 +385,7 @@ const AP_Param::Info var_info[] PROGMEM = {
     // @DisplayName: Channel 6 Tuning
     // @Description: Controls which parameters (normally PID gains) are being tuned with transmitter's channel 6 knob
     // @User: Standard
-    // @Values: 0:None,1:Stab Roll/Pitch kP,4:Rate Roll/Pitch kP,5:Rate Roll/Pitch kI,21:Rate Roll/Pitch kD,3:Stab Yaw kP,6:Rate Yaw kP,26:Rate Yaw kD,14:Altitude Hold kP,7:Throttle Rate kP,37:Throttle Rate kD,34:Throttle Accel kP,35:Throttle Accel kI,36:Throttle Accel kD,12:Loiter Pos kP,22:Loiter Rate kP,28:Loiter Rate kI,23:Loiter Rate kD,10:WP Speed,25:Acro RollPitch kP,40:Acro Yaw kP,9:Relay On/Off,13:Heli Ext Gyro,17:OF Loiter kP,18:OF Loiter kI,19:OF Loiter kD,30:AHRS Yaw kP,31:AHRS kP,32:INAV_TC,38:Declination,39:Circle Rate
+    // @Values: 0:None,1:Stab Roll/Pitch kP,4:Rate Roll/Pitch kP,5:Rate Roll/Pitch kI,21:Rate Roll/Pitch kD,3:Stab Yaw kP,6:Rate Yaw kP,26:Rate Yaw kD,14:Altitude Hold kP,7:Throttle Rate kP,37:Throttle Rate kD,34:Throttle Accel kP,35:Throttle Accel kI,36:Throttle Accel kD,12:Loiter Pos kP,22:Loiter Rate kP,28:Loiter Rate kI,23:Loiter Rate kD,10:WP Speed,25:Acro RollPitch kP,40:Acro Yaw kP,9:Relay On/Off,13:Heli Ext Gyro,17:OF Loiter kP,18:OF Loiter kI,19:OF Loiter kD,30:AHRS Yaw kP,31:AHRS kP,32:INAV_TC,38:Declination,39:Circle Rate,41:Sonar Gain
     GSCALAR(radio_tuning, "TUNE",                   0),
 
     // @Param: TUNE_LOW

ArduCopter/defines.h

@@ -178,6 +178,7 @@
 #define CH6_INAV_TC                     32  // inertial navigation baro/accel and gps/accel time constant (1.5 = strong baro/gps correction on accel estimatehas very strong does not correct accel estimate, 7 = very weak correction)
 #define CH6_DECLINATION                 38  // compass declination in radians
 #define CH6_CIRCLE_RATE                 39  // circle turn rate in degrees (hard coded to about 45 degrees in either direction)
+#define CH6_SONAR_GAIN                  41  // sonar gain
 
 // Acro Trainer types
 #define ACRO_TRAINER_DISABLED   0