ardupilot/APMrover2/mode_follow.cpp
Randy Mackay 84bda4e893 Rover: follow mode fixes and improvements
fix follow endless loop on enter
pass mavlink messages to AP_Follow
separate follow from guided
follow slows based on yaw error
check follow is enabled before entering follow mode
fix order in switch statement when converting from mode number to mode object
remove unused last_log_ms from follow mode
2018-07-18 15:11:09 +09:00

74 lines
2.2 KiB
C++

#include "mode.h"
#include "Rover.h"
// initialize follow mode
bool ModeFollow::_enter()
{
if (!g2.follow.enabled()) {
return false;
}
// initialise waypoint speed
set_desired_speed_to_default();
// initialise heading to current heading
_desired_yaw_cd = ahrs.yaw_sensor;
_yaw_error_cd = 0.0f;
return true;
}
void ModeFollow::update()
{
// stop vehicle if no speed estimate
float speed;
if (!attitude_control.get_forward_speed(speed)) {
// no valid speed so stop
g2.motors.set_throttle(0.0f);
g2.motors.set_steering(0.0f);
return;
}
Vector3f dist_vec; // vector to lead vehicle
Vector3f dist_vec_offs; // vector to lead vehicle + offset
Vector3f vel_of_target; // velocity of lead vehicle
// if no target simply stop the vehicle
if (!g2.follow.get_target_dist_and_vel_ned(dist_vec, dist_vec_offs, vel_of_target)) {
_reached_destination = true;
stop_vehicle();
return;
}
// calculate desired velocity vector
Vector2f desired_velocity_ne;
const float kp = g2.follow.get_pos_p().kP();
desired_velocity_ne.x = vel_of_target.x + (dist_vec_offs.x * kp);
desired_velocity_ne.y = vel_of_target.y + (dist_vec_offs.y * kp);
// if desired velocity is zero stop vehicle
if (is_zero(desired_velocity_ne.x) && is_zero(desired_velocity_ne.y)) {
_reached_destination = true;
stop_vehicle();
return;
}
// we have not reached the target
_reached_destination = false;
// scale desired velocity to stay within horizontal speed limit
float desired_speed = safe_sqrt(sq(desired_velocity_ne.x) + sq(desired_velocity_ne.y));
if (!is_zero(desired_speed) && (desired_speed > _desired_speed)) {
const float scalar_xy = _desired_speed / desired_speed;
desired_velocity_ne *= scalar_xy;
desired_speed = _desired_speed;
}
// calculate vehicle heading
_desired_yaw_cd = wrap_180_cd(atan2f(desired_velocity_ne.y, desired_velocity_ne.x) * DEGX100);
// run steering and throttle controllers
calc_steering_to_heading(_desired_yaw_cd, desired_speed < 0);
calc_throttle(calc_reduced_speed_for_turn_or_distance(desired_speed), false, true);
}