ardupilot/ArduCopter/mode_drift.cpp

130 lines
4.7 KiB
C++

#include "Copter.h"
#if MODE_DRIFT_ENABLED == ENABLED
/*
* Init and run calls for drift flight mode
*/
#ifndef DRIFT_SPEEDGAIN
# define DRIFT_SPEEDGAIN 8.0f
#endif
#ifndef DRIFT_SPEEDLIMIT
# define DRIFT_SPEEDLIMIT 560.0f
#endif
#ifndef DRIFT_THR_ASSIST_GAIN
# define DRIFT_THR_ASSIST_GAIN 0.0018f // gain controlling amount of throttle assistance
#endif
#ifndef DRIFT_THR_ASSIST_MAX
# define DRIFT_THR_ASSIST_MAX 0.3f // maximum assistance throttle assist will provide
#endif
#ifndef DRIFT_THR_MIN
# define DRIFT_THR_MIN 0.213f // throttle assist will be active when pilot's throttle is above this value
#endif
#ifndef DRIFT_THR_MAX
# define DRIFT_THR_MAX 0.787f // throttle assist will be active when pilot's throttle is below this value
#endif
// drift_init - initialise drift controller
bool Copter::ModeDrift::init(bool ignore_checks)
{
if (copter.position_ok() || ignore_checks) {
return true;
}else{
return false;
}
}
// drift_run - runs the drift controller
// should be called at 100hz or more
void Copter::ModeDrift::run()
{
static float braker = 0.0f;
static float roll_input = 0.0f;
float target_roll, target_pitch;
float target_yaw_rate;
float pilot_throttle_scaled;
// if landed and throttle at zero, set throttle to zero and exit immediately
if (!motors->armed() || !motors->get_interlock() || (ap.land_complete && ap.throttle_zero)) {
zero_throttle_and_relax_ac(copter.is_tradheli() && motors->get_interlock());
return;
}
// clear landing flag above zero throttle
if (!ap.throttle_zero) {
set_land_complete(false);
}
// convert pilot input to lean angles
get_pilot_desired_lean_angles(target_roll, target_pitch, copter.aparm.angle_max, copter.aparm.angle_max);
// get pilot's desired throttle
pilot_throttle_scaled = get_pilot_desired_throttle(channel_throttle->get_control_in());
// Grab inertial velocity
const Vector3f& vel = inertial_nav.get_velocity();
// rotate roll, pitch input from north facing to vehicle's perspective
float roll_vel = vel.y * ahrs.cos_yaw() - vel.x * ahrs.sin_yaw(); // body roll vel
float pitch_vel = vel.y * ahrs.sin_yaw() + vel.x * ahrs.cos_yaw(); // body pitch vel
// gain sceduling for Yaw
float pitch_vel2 = MIN(fabsf(pitch_vel), 2000);
target_yaw_rate = ((float)target_roll/1.0f) * (1.0f - (pitch_vel2 / 5000.0f)) * g.acro_yaw_p;
roll_vel = constrain_float(roll_vel, -DRIFT_SPEEDLIMIT, DRIFT_SPEEDLIMIT);
pitch_vel = constrain_float(pitch_vel, -DRIFT_SPEEDLIMIT, DRIFT_SPEEDLIMIT);
roll_input = roll_input * .96f + (float)channel_yaw->get_control_in() * .04f;
//convert user input into desired roll velocity
float roll_vel_error = roll_vel - (roll_input / DRIFT_SPEEDGAIN);
// Roll velocity is feed into roll acceleration to minimize slip
target_roll = roll_vel_error * -DRIFT_SPEEDGAIN;
target_roll = constrain_float(target_roll, -4500.0f, 4500.0f);
// If we let go of sticks, bring us to a stop
if(is_zero(target_pitch)){
// .14/ (.03 * 100) = 4.6 seconds till full braking
braker += .03f;
braker = MIN(braker, DRIFT_SPEEDGAIN);
target_pitch = pitch_vel * braker;
}else{
braker = 0.0f;
}
// set motors to full range
motors->set_desired_spool_state(AP_Motors::DESIRED_THROTTLE_UNLIMITED);
// call attitude controller
attitude_control->input_euler_angle_roll_pitch_euler_rate_yaw(target_roll, target_pitch, target_yaw_rate);
// output pilot's throttle with angle boost
attitude_control->set_throttle_out(get_throttle_assist(vel.z, pilot_throttle_scaled), true, g.throttle_filt);
}
// get_throttle_assist - return throttle output (range 0 ~ 1) based on pilot input and z-axis velocity
float Copter::ModeDrift::get_throttle_assist(float velz, float pilot_throttle_scaled)
{
// throttle assist - adjusts throttle to slow the vehicle's vertical velocity
// Only active when pilot's throttle is between 213 ~ 787
// Assistance is strongest when throttle is at mid, drops linearly to no assistance at 213 and 787
float thr_assist = 0.0f;
if (pilot_throttle_scaled > DRIFT_THR_MIN && pilot_throttle_scaled < DRIFT_THR_MAX) {
// calculate throttle assist gain
thr_assist = 1.2f - ((float)fabsf(pilot_throttle_scaled - 0.5f) / 0.24f);
thr_assist = constrain_float(thr_assist, 0.0f, 1.0f) * -DRIFT_THR_ASSIST_GAIN * velz;
// ensure throttle assist never adjusts the throttle by more than 300 pwm
thr_assist = constrain_float(thr_assist, -DRIFT_THR_ASSIST_MAX, DRIFT_THR_ASSIST_MAX);
}
return constrain_float(pilot_throttle_scaled + thr_assist, 0.0f, 1.0f);
}
#endif