2025-05-13 10:23:35 +02:00

335 lines
14 KiB
C++

/****************************************************************************
*
* Copyright (c) 2025 PX4 Development Team. All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
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#include "DifferentialPosControl.hpp"
using namespace time_literals;
DifferentialPosControl::DifferentialPosControl(ModuleParams *parent) : ModuleParams(parent)
{
_differential_velocity_setpoint_pub.advertise();
_rover_position_setpoint_pub.advertise();
_pure_pursuit_status_pub.advertise();
// Initially set to NaN to indicate that the rover has no position setpoint
_rover_position_setpoint.position_ned[0] = NAN;
_rover_position_setpoint.position_ned[1] = NAN;
updateParams();
}
void DifferentialPosControl::updateParams()
{
ModuleParams::updateParams();
_max_yaw_rate = _param_ro_yaw_rate_limit.get() * M_DEG_TO_RAD_F;
}
void DifferentialPosControl::updatePosControl()
{
const hrt_abstime timestamp_prev = _timestamp;
_timestamp = hrt_absolute_time();
_dt = math::constrain(_timestamp - timestamp_prev, 1_ms, 5000_ms) * 1e-6f;
updateSubscriptions();
if (_vehicle_control_mode.flag_control_position_enabled && _vehicle_control_mode.flag_armed && runSanityChecks()) {
if (_vehicle_control_mode.flag_control_offboard_enabled) {
generatePositionSetpoint();
}
generateVelocitySetpoint();
}
}
void DifferentialPosControl::updateSubscriptions()
{
if (_vehicle_control_mode_sub.updated()) {
_vehicle_control_mode_sub.copy(&_vehicle_control_mode);
}
if (_vehicle_attitude_sub.updated()) {
vehicle_attitude_s vehicle_attitude{};
_vehicle_attitude_sub.copy(&vehicle_attitude);
_vehicle_attitude_quaternion = matrix::Quatf(vehicle_attitude.q);
_vehicle_yaw = matrix::Eulerf(_vehicle_attitude_quaternion).psi();
}
if (_vehicle_local_position_sub.updated()) {
vehicle_local_position_s vehicle_local_position{};
_vehicle_local_position_sub.copy(&vehicle_local_position);
if (!_global_ned_proj_ref.isInitialized()
|| (_global_ned_proj_ref.getProjectionReferenceTimestamp() != vehicle_local_position.ref_timestamp)) {
_global_ned_proj_ref.initReference(vehicle_local_position.ref_lat, vehicle_local_position.ref_lon,
vehicle_local_position.ref_timestamp);
}
_curr_pos_ned = Vector2f(vehicle_local_position.x, vehicle_local_position.y);
Vector3f velocity_ned(vehicle_local_position.vx, vehicle_local_position.vy, vehicle_local_position.vz);
Vector3f velocity_xyz = _vehicle_attitude_quaternion.rotateVectorInverse(velocity_ned);
Vector2f velocity_2d = Vector2f(velocity_xyz(0), velocity_xyz(1));
_vehicle_speed = velocity_2d.norm() > _param_ro_speed_th.get() ? sign(velocity_2d(0)) * velocity_2d.norm() : 0.f;
}
}
void DifferentialPosControl::generatePositionSetpoint()
{
if (_offboard_control_mode_sub.updated()) {
_offboard_control_mode_sub.copy(&_offboard_control_mode);
}
if (!_offboard_control_mode.position) {
return;
}
trajectory_setpoint_s trajectory_setpoint{};
_trajectory_setpoint_sub.copy(&trajectory_setpoint);
// Translate trajectory setpoint to rover position setpoint
rover_position_setpoint_s rover_position_setpoint{};
rover_position_setpoint.timestamp = _timestamp;
rover_position_setpoint.position_ned[0] = trajectory_setpoint.position[0];
rover_position_setpoint.position_ned[1] = trajectory_setpoint.position[1];
rover_position_setpoint.cruising_speed = _param_ro_speed_limit.get();
rover_position_setpoint.yaw = NAN;
_rover_position_setpoint_pub.publish(rover_position_setpoint);
}
void DifferentialPosControl::generateVelocitySetpoint()
{
if (_vehicle_control_mode.flag_control_manual_enabled && _vehicle_control_mode.flag_control_position_enabled) {
manualPositionMode();
} else if (_vehicle_control_mode.flag_control_auto_enabled) {
autoPositionMode();
} else if (_rover_position_setpoint_sub.copy(&_rover_position_setpoint)
&& PX4_ISFINITE(_rover_position_setpoint.position_ned[0]) && PX4_ISFINITE(_rover_position_setpoint.position_ned[1])) {
goToPositionMode();
}
}
void DifferentialPosControl::manualPositionMode()
{
manual_control_setpoint_s manual_control_setpoint{};
_manual_control_setpoint_sub.copy(&manual_control_setpoint);
const float speed_setpoint = math::interpolate<float>(manual_control_setpoint.throttle,
-1.f, 1.f, -_param_ro_speed_limit.get(), _param_ro_speed_limit.get());
const float bearing_scaling = math::min(_max_yaw_rate / _param_ro_yaw_p.get(),
_param_rd_trans_drv_trn.get() - FLT_EPSILON);
const float bearing_delta = math::interpolate<float>(math::deadzone(manual_control_setpoint.roll,
_param_ro_yaw_stick_dz.get()), -1.f, 1.f, -bearing_scaling, bearing_scaling);
if (fabsf(speed_setpoint) < FLT_EPSILON) { // Turn on spot
_course_control = false;
const float bearing_setpoint = matrix::wrap_pi(_vehicle_yaw + bearing_delta);
differential_velocity_setpoint_s differential_velocity_setpoint{};
differential_velocity_setpoint.timestamp = _timestamp;
differential_velocity_setpoint.speed = 0.f;
differential_velocity_setpoint.bearing = bearing_setpoint;
_differential_velocity_setpoint_pub.publish(differential_velocity_setpoint);
} else if (fabsf(bearing_delta) > FLT_EPSILON) { // Closed loop yaw rate control
_course_control = false;
const float bearing_setpoint = matrix::wrap_pi(_vehicle_yaw + bearing_delta);
differential_velocity_setpoint_s differential_velocity_setpoint{};
differential_velocity_setpoint.timestamp = _timestamp;
differential_velocity_setpoint.speed = speed_setpoint;
differential_velocity_setpoint.bearing = bearing_setpoint;
_differential_velocity_setpoint_pub.publish(differential_velocity_setpoint);
} else { // Course control if the steering input is zero (keep driving on a straight line)
if (!_course_control) {
_pos_ctl_course_direction = Vector2f(cos(_vehicle_yaw), sin(_vehicle_yaw));
_pos_ctl_start_position_ned = _curr_pos_ned;
_course_control = true;
}
// Construct a 'target waypoint' for course control s.t. it is never within the maximum lookahead of the rover
const Vector2f start_to_curr_pos = _curr_pos_ned - _pos_ctl_start_position_ned;
const float vector_scaling = fabsf(start_to_curr_pos * _pos_ctl_course_direction) + _param_pp_lookahd_max.get();
const Vector2f target_waypoint_ned = _pos_ctl_start_position_ned + sign(speed_setpoint) *
vector_scaling * _pos_ctl_course_direction;
pure_pursuit_status_s pure_pursuit_status{};
pure_pursuit_status.timestamp = _timestamp;
const float bearing_setpoint = PurePursuit::calcTargetBearing(pure_pursuit_status, _param_pp_lookahd_gain.get(),
_param_pp_lookahd_max.get(), _param_pp_lookahd_min.get(), target_waypoint_ned, _pos_ctl_start_position_ned,
_curr_pos_ned, fabsf(speed_setpoint));
_pure_pursuit_status_pub.publish(pure_pursuit_status);
differential_velocity_setpoint_s differential_velocity_setpoint{};
differential_velocity_setpoint.timestamp = _timestamp;
differential_velocity_setpoint.speed = speed_setpoint;
differential_velocity_setpoint.bearing = speed_setpoint > -FLT_EPSILON ? bearing_setpoint : matrix::wrap_pi(
bearing_setpoint + M_PI_F);
_differential_velocity_setpoint_pub.publish(differential_velocity_setpoint);
}
}
void DifferentialPosControl::autoPositionMode()
{
if (_position_setpoint_triplet_sub.updated()) {
position_setpoint_triplet_s position_setpoint_triplet{};
_position_setpoint_triplet_sub.copy(&position_setpoint_triplet);
_curr_wp_type = position_setpoint_triplet.current.type;
RoverControl::globalToLocalSetpointTriplet(_curr_wp_ned, _prev_wp_ned, _next_wp_ned, position_setpoint_triplet,
_curr_pos_ned, _global_ned_proj_ref);
_waypoint_transition_angle = RoverControl::calcWaypointTransitionAngle(_prev_wp_ned, _curr_wp_ned, _next_wp_ned);
// Waypoint cruising speed
_cruising_speed = position_setpoint_triplet.current.cruising_speed > 0.f ? math::constrain(
position_setpoint_triplet.current.cruising_speed, 0.f, _param_ro_speed_limit.get()) : _param_ro_speed_limit.get();
}
// Distances to waypoints
const float distance_to_curr_wp = sqrt(powf(_curr_pos_ned(0) - _curr_wp_ned(0),
2) + powf(_curr_pos_ned(1) - _curr_wp_ned(1), 2));
// Check stopping conditions
bool auto_stop{false};
if (_curr_wp_type == position_setpoint_s::SETPOINT_TYPE_LAND
|| _curr_wp_type == position_setpoint_s::SETPOINT_TYPE_IDLE
|| !_next_wp_ned.isAllFinite()) { // Check stopping conditions
auto_stop = distance_to_curr_wp < _param_nav_acc_rad.get();
}
if (auto_stop) {
differential_velocity_setpoint_s differential_velocity_setpoint{};
differential_velocity_setpoint.timestamp = _timestamp;
differential_velocity_setpoint.speed = 0.f;
differential_velocity_setpoint.bearing = _vehicle_yaw;
_differential_velocity_setpoint_pub.publish(differential_velocity_setpoint);
} else {
const float speed_setpoint = calcSpeedSetpoint(_cruising_speed, distance_to_curr_wp, _param_ro_decel_limit.get(),
_param_ro_jerk_limit.get(), _waypoint_transition_angle, _param_ro_speed_limit.get(), _param_rd_trans_drv_trn.get(),
_param_rd_miss_spd_gain.get(), _curr_wp_type);
pure_pursuit_status_s pure_pursuit_status{};
pure_pursuit_status.timestamp = _timestamp;
const float bearing_setpoint = PurePursuit::calcTargetBearing(pure_pursuit_status, _param_pp_lookahd_gain.get(),
_param_pp_lookahd_max.get(), _param_pp_lookahd_min.get(), _curr_wp_ned, _prev_wp_ned, _curr_pos_ned,
fabsf(speed_setpoint));
_pure_pursuit_status_pub.publish(pure_pursuit_status);
differential_velocity_setpoint_s differential_velocity_setpoint{};
differential_velocity_setpoint.timestamp = _timestamp;
differential_velocity_setpoint.speed = speed_setpoint;
differential_velocity_setpoint.bearing = bearing_setpoint;
_differential_velocity_setpoint_pub.publish(differential_velocity_setpoint);
}
}
float DifferentialPosControl::calcSpeedSetpoint(const float cruising_speed, const float distance_to_curr_wp,
const float max_decel, const float max_jerk, const float waypoint_transition_angle, const float max_speed,
const float trans_drv_trn, const float miss_spd_gain, int curr_wp_type)
{
// Upcoming stop
if (max_decel > FLT_EPSILON && max_jerk > FLT_EPSILON && (!PX4_ISFINITE(waypoint_transition_angle)
|| _waypoint_transition_angle < M_PI_F - trans_drv_trn || curr_wp_type == position_setpoint_s::SETPOINT_TYPE_LAND
|| curr_wp_type == position_setpoint_s::SETPOINT_TYPE_IDLE)) {
const float straight_line_speed = math::trajectory::computeMaxSpeedFromDistance(max_jerk,
max_decel, distance_to_curr_wp, 0.f);
return math::min(straight_line_speed, cruising_speed);
}
// Straight line speed
if (max_jerk > FLT_EPSILON && max_decel > FLT_EPSILON && miss_spd_gain > FLT_EPSILON) {
const float speed_reduction = math::constrain(miss_spd_gain * math::interpolate(M_PI_F - _waypoint_transition_angle,
0.f, M_PI_F, 0.f, 1.f), 0.f, 1.f);
const float straight_line_speed = math::trajectory::computeMaxSpeedFromDistance(max_jerk, max_decel,
distance_to_curr_wp,
max_speed * (1.f - speed_reduction));
return math::min(straight_line_speed, cruising_speed);
}
return cruising_speed; // Fallthrough
}
void DifferentialPosControl::goToPositionMode()
{
const Vector2f target_waypoint_ned(_rover_position_setpoint.position_ned[0], _rover_position_setpoint.position_ned[1]);
const float distance_to_target = (target_waypoint_ned - _curr_pos_ned).norm();
if (distance_to_target > _param_nav_acc_rad.get()) {
float speed_setpoint = math::trajectory::computeMaxSpeedFromDistance(_param_ro_jerk_limit.get(),
_param_ro_decel_limit.get(), distance_to_target, 0.f);
const float max_speed = PX4_ISFINITE(_rover_position_setpoint.cruising_speed) ?
_rover_position_setpoint.cruising_speed :
_param_ro_speed_limit.get();
speed_setpoint = math::min(speed_setpoint, max_speed);
pure_pursuit_status_s pure_pursuit_status{};
pure_pursuit_status.timestamp = _timestamp;
const float bearing_setpoint = PurePursuit::calcTargetBearing(pure_pursuit_status, _param_pp_lookahd_gain.get(),
_param_pp_lookahd_max.get(), _param_pp_lookahd_min.get(), target_waypoint_ned, _curr_pos_ned,
_curr_pos_ned, fabsf(speed_setpoint));
_pure_pursuit_status_pub.publish(pure_pursuit_status);
differential_velocity_setpoint_s differential_velocity_setpoint{};
differential_velocity_setpoint.timestamp = _timestamp;
differential_velocity_setpoint.speed = speed_setpoint;
differential_velocity_setpoint.bearing = bearing_setpoint;
_differential_velocity_setpoint_pub.publish(differential_velocity_setpoint);
} else {
differential_velocity_setpoint_s differential_velocity_setpoint{};
differential_velocity_setpoint.timestamp = _timestamp;
differential_velocity_setpoint.speed = 0.f;
differential_velocity_setpoint.bearing = _vehicle_yaw;
_differential_velocity_setpoint_pub.publish(differential_velocity_setpoint);
}
}
bool DifferentialPosControl::runSanityChecks()
{
bool ret = true;
if (_param_ro_yaw_rate_limit.get() < FLT_EPSILON) {
ret = false;
}
if (_param_ro_speed_limit.get() < FLT_EPSILON) {
ret = false;
}
_prev_param_check_passed = ret;
return ret;
}