Rover: balancebot_pitch_control method removes unused armed arg

Also remove constraint on throttle output (this is handle in the AP_MotorsUGV library
Also move balance bot declarations to alphabetical order within Rover.h

APMrover2/Rover.h

@@ -388,6 +388,10 @@ private:
     void update_GPS(void);
     void update_current_mode(void);
 
+    // balance_bot.cpp
+    void balancebot_pitch_control(float &throttle);
+    bool is_balancebot() const;
+
     // capabilities.cpp
     void init_capabilities(void);
 
@@ -552,11 +556,6 @@ private:
 public:
     void mavlink_delay_cb();
     void failsafe_check();
-
-    // BalanceBot.cpp
-    void balancebot_pitch_control(float &, bool);
-    bool is_balancebot() const;
-
     void update_soft_armed();
     // Motor test
     void motor_test_output();

APMrover2/balance_bot.cpp

@@ -2,16 +2,13 @@
 #include "Rover.h"
 
 // Function to set a desired pitch angle according to throttle
-void Rover::balancebot_pitch_control(float &throttle, bool armed)
+void Rover::balancebot_pitch_control(float &throttle)
 {
     // calculate desired pitch angle
     const float demanded_pitch = radians(-throttle * 0.01f * g2.bal_pitch_max);
 
     // calculate required throttle using PID controller
-    const float balance_throttle = g2.attitude_control.get_throttle_out_from_pitch(demanded_pitch, g2.motors.limit.throttle_lower, g2.motors.limit.throttle_upper, G_Dt) * 100.0f;
-
-    // constrain throttle between -100 and 100
-    throttle = constrain_float(balance_throttle, -100.0f, 100.0f);
+    throttle = g2.attitude_control.get_throttle_out_from_pitch(demanded_pitch, g2.motors.limit.throttle_lower, g2.motors.limit.throttle_upper, G_Dt) * 100.0f;
 }
 
 // returns true if vehicle is a balance bot

APMrover2/mode.cpp

@@ -267,7 +267,7 @@ void Mode::calc_throttle(float target_speed, bool nudge_allowed, bool avoidance_
 
     // if vehicle is balance bot, calculate actual throttle required for balancing
     if (rover.is_balancebot()) {
-        rover.balancebot_pitch_control(throttle_out, rover.arming.is_armed());
+        rover.balancebot_pitch_control(throttle_out);
     }
 
     // send to motor
@@ -283,7 +283,7 @@ bool Mode::stop_vehicle()
 
     // if vehicle is balance bot, calculate actual throttle required for balancing
     if (rover.is_balancebot()) {
-        rover.balancebot_pitch_control(throttle_out, rover.arming.is_armed());
+        rover.balancebot_pitch_control(throttle_out);
     }
 
     // send to motor

APMrover2/mode_hold.cpp

@@ -7,7 +7,7 @@ void ModeHold::update()
 
     // if vehicle is balance bot, calculate actual throttle required for balancing
     if (rover.is_balancebot()) {
-        rover.balancebot_pitch_control(throttle, rover.arming.is_armed());
+        rover.balancebot_pitch_control(throttle);
     }
 
     // hold position - stop motors and center steering

APMrover2/mode_manual.cpp

@@ -15,7 +15,7 @@ void ModeManual::update()
 
     // if vehicle is balance bot, calculate actual throttle required for balancing
     if (rover.is_balancebot()) {
-        rover.balancebot_pitch_control(desired_throttle, rover.arming.is_armed());
+        rover.balancebot_pitch_control(desired_throttle);
     }
 
     // copy RC scaled inputs to outputs