Rover: rename calc_nav_steer to calc_steering_from_lateral_acceleration

rename calc_lateral_acceleration to calc_steering_to_waypoint
calc_steering_to_waypoint internally calls calc_steering_from_lateral_acceleration
non-functional change

APMrover2/mode.cpp

@@ -190,7 +190,7 @@ float Mode::calc_reduced_speed_for_turn_or_distance(float desired_speed)
 
 // calculate the lateral acceleration target to cause the vehicle to drive along the path from origin to destination
 // this function update lateral_acceleration and _yaw_error_cd members
-void Mode::calc_lateral_acceleration(const struct Location &origin, const struct Location &destination, bool reversed)
+void Mode::calc_steering_to_waypoint(const struct Location &origin, const struct Location &destination, bool reversed)
 {
     // Calculate the required turn of the wheels
     // negative error = left turn
@@ -210,12 +210,15 @@ void Mode::calc_lateral_acceleration(const struct Location &origin, const struct
             lateral_acceleration = -g.turn_max_g * GRAVITY_MSS;
         }
     }
+
+    // call lateral acceleration to steering controller
+    calc_steering_from_lateral_acceleration(reversed);
 }
 
 /*
-    calculate steering angle given lateral_acceleration
+    calculate steering output given lateral_acceleration
 */
-void Mode::calc_nav_steer(bool reversed)
+void Mode::calc_steering_from_lateral_acceleration(bool reversed)
 {
     // add obstacle avoidance response to lateral acceleration target
     if (!reversed) {

APMrover2/mode.h

@@ -92,10 +92,10 @@ protected:
     virtual void _exit() { return; }
 
     // calculate steering angle given a desired lateral acceleration
-    void calc_nav_steer(bool reversed = false);
+    void calc_steering_from_lateral_acceleration(bool reversed = false);
 
-    // calculate desired lateral acceleration
-    void calc_lateral_acceleration(const struct Location &origin, const struct Location &destination, bool reversed = false);
+    // calculate steering output to drive along line from origin to destination waypoint
+    void calc_steering_to_waypoint(const struct Location &origin, const struct Location &destination, bool reversed = false);
 
     // calculates the amount of throttle that should be output based
     // on things like proximity to corners and current speed
@@ -114,7 +114,7 @@ protected:
     float calc_speed_nudge(float target_speed, float cruise_speed, float cruise_throttle);
 
     // calculated a reduced speed(in m/s) based on yaw error and lateral acceleration and/or distance to a waypoint
-    // should be called after calc_lateral_acceleration and before calc_throttle
+    // should be called after calc_steering_to_waypoint and before calc_throttle
     // relies on these internal members being updated: lateral_acceleration, _yaw_error_cd, _distance_to_destination
     float calc_reduced_speed_for_turn_or_distance(float desired_speed);
 

APMrover2/mode_auto.cpp

@@ -54,8 +54,7 @@ void ModeAuto::update()
             bool active_at_destination = _reached_destination && _stay_active_at_dest && (_distance_to_destination > rover.g.waypoint_radius);
             if (!_reached_destination || active_at_destination) {
                 // continue driving towards destination
-                calc_lateral_acceleration(active_at_destination ? rover.current_loc : _origin, _destination, _reversed);
-                calc_nav_steer(_reversed);
+                calc_steering_to_waypoint(active_at_destination ? rover.current_loc : _origin, _destination, _reversed);
                 calc_throttle(calc_reduced_speed_for_turn_or_distance(_reversed ? -_desired_speed : _desired_speed), true);
             } else {
                 // we have reached the destination so stop

APMrover2/mode_guided.cpp

@@ -30,8 +30,7 @@ void ModeGuided::update()
                     rover.gcs().send_mission_item_reached_message(0);
                 }
                 // drive towards destination
-                calc_lateral_acceleration(_origin, _destination);
-                calc_nav_steer();
+                calc_steering_to_waypoint(_origin, _destination);
                 calc_throttle(calc_reduced_speed_for_turn_or_distance(_desired_speed), true);
             } else {
                 stop_vehicle();

APMrover2/mode_rtl.cpp

@@ -29,8 +29,7 @@ void ModeRTL::update()
             gcs().send_text(MAV_SEVERITY_INFO, "Reached destination");
         }
         // continue driving towards destination
-        calc_lateral_acceleration(_origin, _destination);
-        calc_nav_steer();
+        calc_steering_to_waypoint(_origin, _destination);
         calc_throttle(calc_reduced_speed_for_turn_or_distance(_desired_speed), true);
     } else {
         // we've reached destination so stop

APMrover2/mode_steering.cpp

@@ -49,8 +49,8 @@ void ModeSteering::update()
     if (is_zero(target_speed) && !is_pivot_turning) {
         stop_vehicle();
     } else {
-        // run steering controller
-        calc_nav_steer(reversed);
+        // run lateral acceleration to steering controller
+        calc_steering_from_lateral_acceleration(false);
         calc_throttle(target_speed, false);
     }
 }