From 289b1ca75a26fb85ab26e170f5ae3db45d611aa1 Mon Sep 17 00:00:00 2001 From: Leonard Hall Date: Thu, 27 Jan 2022 19:07:38 +1030 Subject: [PATCH] AC_WPNav: Support pause --- libraries/AC_WPNav/AC_WPNav.cpp | 44 ++++++++++++++++++++------------- libraries/AC_WPNav/AC_WPNav.h | 12 +++++++-- 2 files changed, 37 insertions(+), 19 deletions(-) diff --git a/libraries/AC_WPNav/AC_WPNav.cpp b/libraries/AC_WPNav/AC_WPNav.cpp index d149094434..032a013d45 100644 --- a/libraries/AC_WPNav/AC_WPNav.cpp +++ b/libraries/AC_WPNav/AC_WPNav.cpp @@ -197,8 +197,9 @@ void AC_WPNav::wp_and_spline_init(float speed_cms, Vector3f stopping_point) _this_leg_is_spline = false; // initialise the terrain velocity to the current maximum velocity - _terrain_vel = _wp_desired_speed_xy_cms; - _terrain_accel = 0.0; + _offset_vel = _wp_desired_speed_xy_cms; + _offset_accel = 0.0; + _paused = false; // mark as active _wp_last_update = AP_HAL::millis(); @@ -209,8 +210,8 @@ void AC_WPNav::set_speed_xy(float speed_cms) { // range check target speed and protect against divide by zero if (speed_cms >= WPNAV_WP_SPEED_MIN && is_positive(_wp_desired_speed_xy_cms)) { - // update terrain following speed scalar - _terrain_vel = speed_cms * _terrain_vel / _wp_desired_speed_xy_cms; + // update horizontal velocity speed offset scalar + _offset_vel = speed_cms * _offset_vel / _wp_desired_speed_xy_cms; // initialize the desired wp speed _wp_desired_speed_xy_cms = speed_cms; @@ -463,14 +464,14 @@ bool AC_WPNav::advance_wp_target_along_track(float dt) // get current position and adjust altitude to origin and destination's frame (i.e. _frame) const Vector3f &curr_pos = _inav.get_position_neu_cm() - Vector3f{0, 0, terr_offset}; - - // Use _track_scalar_dt to slow down S-Curve time to prevent target moving too far in front of aircraft Vector3f curr_target_vel = _pos_control.get_vel_desired_cms(); curr_target_vel.z -= _pos_control.get_vel_offset_z_cms(); + // Use _track_scalar_dt to slow down progression of the position target moving too far in front of aircraft + // _track_scalar_dt does not scale the velocity or acceleration float track_scaler_dt = 1.0f; // check target velocity is non-zero - if (is_positive(curr_target_vel.length())) { + if (is_positive(curr_target_vel.length_squared())) { Vector3f track_direction = curr_target_vel.normalized(); const float track_error = _pos_control.get_pos_error_cm().dot(track_direction); const float track_velocity = _inav.get_velocity_neu_cms().dot(track_direction); @@ -478,13 +479,15 @@ bool AC_WPNav::advance_wp_target_along_track(float dt) track_scaler_dt = constrain_float(0.05f + (track_velocity - _pos_control.get_pos_xy_p().kP() * track_error) / curr_target_vel.length(), 0.1f, 1.0f); } - float vel_time_scalar = 1.0; + // Use vel_scaler_dt to slow down the trajectory time + // vel_scaler_dt scales the velocity and acceleration to be kinematically constent + float vel_scaler_dt = 1.0; if (is_positive(_wp_desired_speed_xy_cms)) { - update_vel_accel(_terrain_vel, _terrain_accel, dt, 0.0, 0.0); - shape_vel_accel( _wp_desired_speed_xy_cms * offset_z_scaler, 0.0, - _terrain_vel, _terrain_accel, - -_wp_accel_cmss, _wp_accel_cmss, _pos_control.get_shaping_jerk_xy_cmsss(), dt, true); - vel_time_scalar = _terrain_vel / _wp_desired_speed_xy_cms; + update_vel_accel(_offset_vel, _offset_accel, dt, 0.0, 0.0); + const float vel_input = !_paused ? _wp_desired_speed_xy_cms * offset_z_scaler : 0.0; + shape_vel_accel(vel_input, 0.0, _offset_vel, _offset_accel, -_wp_accel_cmss, _wp_accel_cmss, + _pos_control.get_shaping_jerk_xy_cmsss(), dt, true); + vel_scaler_dt = _offset_vel / _wp_desired_speed_xy_cms; } // change s-curve time speed with a time constant of maximum acceleration / maximum jerk @@ -501,16 +504,23 @@ bool AC_WPNav::advance_wp_target_along_track(float dt) if (!_this_leg_is_spline) { // update target position, velocity and acceleration target_pos = _origin; - s_finished = _scurve_this_leg.advance_target_along_track(_scurve_prev_leg, _scurve_next_leg, _wp_radius_cm, _scurve_accel_corner, _flags.fast_waypoint, _track_scalar_dt * vel_time_scalar * dt, target_pos, target_vel, target_accel); + s_finished = _scurve_this_leg.advance_target_along_track(_scurve_prev_leg, _scurve_next_leg, _wp_radius_cm, _scurve_accel_corner, _flags.fast_waypoint, _track_scalar_dt * vel_scaler_dt * dt, target_pos, target_vel, target_accel); } else { // splinetarget_vel target_vel = curr_target_vel; - _spline_this_leg.advance_target_along_track(_track_scalar_dt * vel_time_scalar * dt, target_pos, target_vel); + _spline_this_leg.advance_target_along_track(_track_scalar_dt * vel_scaler_dt * dt, target_pos, target_vel); s_finished = _spline_this_leg.reached_destination(); } - target_vel *= vel_time_scalar; - target_accel *= sq(vel_time_scalar); + Vector3f accel_offset; + if (is_positive(target_vel.length_squared())) { + Vector3f track_direction = target_vel.normalized(); + accel_offset = track_direction * _offset_accel * target_vel.length() / _wp_desired_speed_xy_cms; + } + + target_vel *= vel_scaler_dt; + target_accel *= sq(vel_scaler_dt); + target_accel += accel_offset; // convert final_target.z to altitude above the ekf origin target_pos.z += _pos_control.get_pos_offset_z_cm(); diff --git a/libraries/AC_WPNav/AC_WPNav.h b/libraries/AC_WPNav/AC_WPNav.h index 451b4998a2..13fdc4e171 100644 --- a/libraries/AC_WPNav/AC_WPNav.h +++ b/libraries/AC_WPNav/AC_WPNav.h @@ -57,6 +57,13 @@ public: /// set current target horizontal speed during wp navigation void set_speed_xy(float speed_cms); + /// set pause or resume during wp navigation + void set_pause() { _paused = true; } + void set_resume() { _paused = false; } + + /// get paused status + bool paused() { return _paused; } + /// set current target climb or descent rate during wp navigation void set_speed_up(float speed_up_cms); void set_speed_down(float speed_down_cms); @@ -258,8 +265,9 @@ protected: Vector3f _origin; // starting point of trip to next waypoint in cm from ekf origin Vector3f _destination; // target destination in cm from ekf origin float _track_scalar_dt; // time compression multiplier to slow the progress along the track - float _terrain_vel; // maximum horizontal velocity used to ensure the aircraft can maintain height above terrain - float _terrain_accel; // acceleration value used to change _terrain_vel + float _offset_vel; // horizontal velocity reference used to slow the aircraft for pause and to ensure the aircraft can maintain height above terrain + float _offset_accel; // horizontal acceleration reference used to slow the aircraft for pause and to ensure the aircraft can maintain height above terrain + bool _paused; // flag for pausing waypoint controller // terrain following variables bool _terrain_alt; // true if origin and destination.z are alt-above-terrain, false if alt-above-ekf-origin