ardupilot/ArduCopter/control_throw.cpp

232 lines
8.6 KiB
C++

/// -*- tab-width: 4; Mode: C++; c-basic-offset: 4; indent-tabs-mode: nil -*-
#include "Copter.h"
// throw_init - initialise throw controller
bool Copter::throw_init(bool ignore_checks)
{
#if FRAME_CONFIG == HELI_FRAME
// do not allow helis to use throw to start
return false;
#endif
// do not enter the mode when already armed
if (motors.armed()) {
return false;
}
// this mode needs a position reference
return true;
}
// clean up when exiting throw mode
void Copter::throw_exit()
{
// If exiting throw mode before commencing flight, restore the throttle interlock to the value last set by the switch
if (!throw_flight_commenced) {
motors.set_interlock(throw_early_exit_interlock);
}
}
// runs the throw to start controller
// should be called at 100hz or more
void Copter::throw_run()
{
static ThrowModeState throw_state = Throw_Disarmed;
/* Throw State Machine
Throw_Disarmed - motors are off
Throw_Detecting - motors are on and we are waiting for the throw
Throw_Uprighting - the throw has been detected and the copter is being uprighted
Throw_HgtStabilise - the copter is kept level and height is stabilised about the target height
Throw_PosHold - the copter is kept at a constant position and height
*/
// Don't enter THROW mode if interlock will prevent motors running
if (!motors.armed() && motors.get_interlock()) {
// state machine entry is always from a disarmed state
throw_state = Throw_Disarmed;
// remember the current value of the motor interlock so that this condition can be restored if we exit the throw mode before starting motors
throw_early_exit_interlock = true;
// prevent motors from rotating before the throw is detected unless enabled by the user
if (g.throw_motor_start == 1) {
motors.set_interlock(true);
} else {
motors.set_interlock(false);
}
// status to let system know flight control has not started which means the interlock setting needs to restored if we exit to another flight mode
// this is necessary because throw mode uses the interlock to achieve a post arm motor start.
throw_flight_commenced = false;
} else if (throw_state == Throw_Disarmed && motors.armed()) {
gcs_send_text(MAV_SEVERITY_INFO,"waiting for throw");
throw_state = Throw_Detecting;
// prevent motors from rotating before the throw is detected unless enabled by the user
if (g.throw_motor_start == 1) {
motors.set_interlock(true);
} else {
motors.set_interlock(false);
}
} else if (throw_state == Throw_Detecting && throw_detected()){
gcs_send_text(MAV_SEVERITY_INFO,"throw detected - uprighting");
throw_state = Throw_Uprighting;
// Cancel the waiting for throw tone sequence
AP_Notify::flags.waiting_for_throw = false;
// reset the interlock
motors.set_interlock(true);
// status to let system know flight control has started which means the entry interlock setting will not restored if we exit to another flight mode
throw_flight_commenced = true;
} else if (throw_state == Throw_Uprighting && throw_attitude_good()) {
gcs_send_text(MAV_SEVERITY_INFO,"uprighted - controlling height");
throw_state = Throw_HgtStabilise;
// initialize vertical speed and acceleration limits
// use brake mode values for rapid response
pos_control.set_speed_z(BRAKE_MODE_SPEED_Z, BRAKE_MODE_SPEED_Z);
pos_control.set_accel_z(BRAKE_MODE_DECEL_RATE);
// initialise the demanded height to 3m above the throw height
// we want to rapidly clear surrounding obstacles
pos_control.set_alt_target(inertial_nav.get_altitude() + 300);
// set the initial velocity of the height controller demand to the measured velocity if it is going up
// if it is going down, set it to zero to enforce a very hard stop
pos_control.set_desired_velocity_z(fmaxf(inertial_nav.get_velocity_z(),0.0f));
// Set the auto_arm status to true to avoid a possible automatic disarm caused by selection of an auto mode with throttle at minimum
set_auto_armed(true);
} else if (throw_state == Throw_HgtStabilise && throw_height_good()) {
gcs_send_text(MAV_SEVERITY_INFO,"height achieved - controlling position");
throw_state = Throw_PosHold;
// initialise the loiter target to the curent position and velocity
wp_nav.init_loiter_target();
// Set the auto_arm status to true to avoid a possible automatic disarm caused by selection of an auto mode with throttle at minimum
set_auto_armed(true);
}
// Throw State Processing
switch (throw_state) {
case Throw_Disarmed:
// demand zero throttle (motors will be stopped anyway) and continually reset the attitude controller
attitude_control.set_throttle_out_unstabilized(0,true,g.throttle_filt);
motors.slow_start(true);
break;
case Throw_Detecting:
// Hold throttle at zero during the throw and continually reset the attitude controller
attitude_control.set_throttle_out_unstabilized(0,true,g.throttle_filt);
// Play the waiting for throw tone sequence to alert the user
AP_Notify::flags.waiting_for_throw = true;
break;
case Throw_Uprighting:
// demand a level roll/pitch attitude with zero yaw rate
attitude_control.input_euler_angle_roll_pitch_euler_rate_yaw(0.0f, 0.0f, 0.0f);
// output 50% throttle and turn off angle boost to maximise righting moment
attitude_control.set_throttle_out(500, false, g.throttle_filt);
break;
case Throw_HgtStabilise:
// call attitude controller
attitude_control.input_euler_angle_roll_pitch_euler_rate_yaw(0.0f, 0.0f, 0.0f);
// call height controller
pos_control.set_alt_target_from_climb_rate_ff(0.0f, G_Dt, false);
pos_control.update_z_controller();
break;
case Throw_PosHold:
// run loiter controller
wp_nav.update_loiter(ekfGndSpdLimit, ekfNavVelGainScaler);
// call attitude controller
attitude_control.input_euler_angle_roll_pitch_euler_rate_yaw(wp_nav.get_roll(), wp_nav.get_pitch(), 0.0f);
// call height controller
pos_control.set_alt_target_from_climb_rate_ff(0.0f, G_Dt, false);
pos_control.update_z_controller();
break;
}
}
bool Copter::throw_detected()
{
// Check that we have a valid navigation solution
nav_filter_status filt_status = inertial_nav.get_filter_status();
if (!filt_status.flags.attitude || !filt_status.flags.horiz_pos_abs || !filt_status.flags.vert_pos) {
return false;
}
// Check for high speed (note get_inertial_nav methods use a cm length scale)
bool high_speed = inertial_nav.get_velocity().length() > 500.0f;
// check for upwards trajectory
bool gaining_height = inertial_nav.get_velocity().z > 50.0f;
// Check the vertical acceleraton is greater than 0.25g
bool free_falling = ahrs.get_accel_ef().z > -0.25 * GRAVITY_MSS;
// Check if the accel length is < 1.0g indicating that any throw action is complete and the copter has been released
bool no_throw_action = ins.get_accel().length() < 1.0f * GRAVITY_MSS;
// High velocity or free-fall combined with incresing height indicate a possible throw release
bool possible_throw_detected = (free_falling || high_speed) && gaining_height && no_throw_action;
// Record time and vertical velocity when we detect the possible throw
if (possible_throw_detected && ((AP_HAL::millis() - throw_free_fall_start_ms) > 500)) {
throw_free_fall_start_ms = AP_HAL::millis();
throw_free_fall_start_velz = inertial_nav.get_velocity().z;
}
// Once a possible throw condition has been detected, we check for 2.5 m/s of downwards velocity change in less than 0.5 seconds to confirm
bool throw_condition_confirmed = ((AP_HAL::millis() - throw_free_fall_start_ms < 500) && ((inertial_nav.get_velocity().z - throw_free_fall_start_velz) < -250.0f));
// start motors and enter the control mode if we are in continuous freefall
if (throw_condition_confirmed) {
return true;
} else {
return false;
}
}
bool Copter::throw_attitude_good()
{
// Check that we have uprighted the copter
const Matrix3f &rotMat = ahrs.get_rotation_body_to_ned();
bool is_upright = (rotMat.c.z > 0.866f);
return is_upright;
}
bool Copter::throw_height_good()
{
// Check that we are no more than 0.5m below the demanded height
return (pos_control.get_alt_error() < 50.0f);
}