AC_AttitudeControl: add comments

libraries/AC_AttitudeControl/AC_AttitudeControl.cpp

@@ -878,11 +878,13 @@ float AC_AttitudeControl::input_shaping_ang_vel(float target_ang_vel, float desi
     }
 }
 
-// calculates the accleration correction from an rate error. The angular acceleration is limited.
+// calculates the accleration correction from an rate error. The angular acceleration and deceleration is limited.
 float AC_AttitudeControl::input_shaping_rate(float error_rate, float input_tc, float accel_max, float target_ang_vel, float dt)
 {
+    // Calculate the acceleration to smoothly achieve rate. Jerk is not limited.
     float desired_ang_accel = sqrt_controller(error_rate, 1.0f / MAX(input_tc, 0.01f), 0.0f, dt);
 
+    // limit acceleration or deceleration
     if (is_positive(accel_max)) {
         desired_ang_accel = constrain_float(desired_ang_accel, -accel_max, accel_max);
     }

libraries/AC_AttitudeControl/AC_AttitudeControl.h

@@ -309,6 +309,7 @@ public:
     // limits the acceleration and deceleration of a velocity request
     static float input_shaping_ang_vel(float target_ang_vel, float desired_ang_vel, float accel_max, float dt);
 
+    // calculates the accleration correction from an rate error. The angular acceleration and deceleration is limited.
     static float input_shaping_rate(float error_rate, float input_tc, float accel_max, float target_ang_vel, float dt);
 
     // calculates the expected angular velocity correction from an angle error based on the AC_AttitudeControl settings.

libraries/AC_AttitudeControl/AC_CommandModel.cpp

@@ -1,6 +1,9 @@
 #include "AC_CommandModel.h"
 #include <AP_HAL/AP_HAL.h>
 
+// The Commmand Model class holds parameters that shape the pilot desired angular rate input.  This class can 
+// be expanded to hold the methods that shape the pilot desired input.
+
 extern const AP_HAL::HAL& hal;
 
 // table of user settable parameters

libraries/AC_AttitudeControl/AC_CommandModel.h

@@ -16,19 +16,21 @@ public:
             AP_Param::setup_object_defaults(this, var_info);
         }
 
+    // Accessors for parameters
     float get_rate_tc() { return rate_tc; }
     float get_rate() { return rate; }
     float get_expo() { return expo; }
 
+    // Set the max rate
     void set_rate(float input) { rate = input; }
 
     // var_info for holding Parameter information
     static const struct AP_Param::GroupInfo var_info[];
 
 protected:
-    AP_Float rate_tc;
-    AP_Float rate;
-    AP_Float expo;
+    AP_Float rate_tc;       // rate time constant
+    AP_Float rate;          // maximum rate
+    AP_Float expo;          // expo shaping
 
 };