mirror of https://github.com/ArduPilot/ardupilot
99 lines
3.8 KiB
C++
99 lines
3.8 KiB
C++
/// @file AC_HELI_PID.cpp
|
|
/// @brief Generic PID algorithm
|
|
|
|
#include <AP_Math/AP_Math.h>
|
|
#include "AC_HELI_PID.h"
|
|
|
|
const AP_Param::GroupInfo AC_HELI_PID::var_info[] = {
|
|
// @Param: P
|
|
// @DisplayName: PID Proportional Gain
|
|
// @Description: P Gain which produces an output value that is proportional to the current error value
|
|
AP_GROUPINFO("P", 0, AC_HELI_PID, _kp, 0),
|
|
|
|
// @Param: I
|
|
// @DisplayName: PID Integral Gain
|
|
// @Description: I Gain which produces an output that is proportional to both the magnitude and the duration of the error
|
|
AP_GROUPINFO("I", 1, AC_HELI_PID, _ki, 0),
|
|
|
|
// @Param: D
|
|
// @DisplayName: PID Derivative Gain
|
|
// @Description: D Gain which produces an output that is proportional to the rate of change of the error
|
|
AP_GROUPINFO("D", 2, AC_HELI_PID, _kd, 0),
|
|
|
|
// 3 was for uint16 IMAX
|
|
|
|
// @Param: VFF
|
|
// @DisplayName: Velocity FF FeedForward Gain
|
|
// @Description: Velocity FF Gain which produces an output value that is proportional to the demanded input
|
|
AP_GROUPINFO("VFF", 4, AC_HELI_PID, _kff, 0),
|
|
|
|
// @Param: IMAX
|
|
// @DisplayName: PID Integral Maximum
|
|
// @Description: The maximum/minimum value that the I term can output
|
|
AP_GROUPINFO("IMAX", 5, AC_HELI_PID, _kimax, 0),
|
|
|
|
// 6 was for float FILT
|
|
|
|
// @Param: ILMI
|
|
// @DisplayName: I-term Leak Minimum
|
|
// @Description: Point below which I-term will not leak down
|
|
// @Range: 0 1
|
|
// @User: Advanced
|
|
AP_GROUPINFO("ILMI", 7, AC_HELI_PID, _leak_min, AC_PID_LEAK_MIN),
|
|
|
|
// 8 was for float AFF
|
|
|
|
// @Param: FLTT
|
|
// @DisplayName: PID Target filter frequency in Hz
|
|
// @Description: Target filter frequency in Hz
|
|
// @Units: Hz
|
|
AP_GROUPINFO("FLTT", 9, AC_HELI_PID, _filt_T_hz, AC_PID_TFILT_HZ_DEFAULT),
|
|
|
|
// @Param: FLTE
|
|
// @DisplayName: PID Error filter frequency in Hz
|
|
// @Description: Error filter frequency in Hz
|
|
// @Units: Hz
|
|
AP_GROUPINFO("FLTE", 10, AC_HELI_PID, _filt_E_hz, AC_PID_EFILT_HZ_DEFAULT),
|
|
|
|
// @Param: FLTD
|
|
// @DisplayName: PID D term filter frequency in Hz
|
|
// @Description: Derivative filter frequency in Hz
|
|
// @Units: Hz
|
|
AP_GROUPINFO("FLTD", 11, AC_HELI_PID, _filt_D_hz, AC_PID_DFILT_HZ_DEFAULT),
|
|
|
|
// @Param: SMAX
|
|
// @DisplayName: Slew rate limit
|
|
// @Description: Sets an upper limit on the slew rate produced by the combined P and D gains. If the amplitude of the control action produced by the rate feedback exceeds this value, then the D+P gain is reduced to respect the limit. This limits the amplitude of high frequency oscillations caused by an excessive gain. The limit should be set to no more than 25% of the actuators maximum slew rate to allow for load effects. Note: The gain will not be reduced to less than 10% of the nominal value. A value of zero will disable this feature.
|
|
// @Range: 0 200
|
|
// @Increment: 0.5
|
|
// @User: Advanced
|
|
AP_GROUPINFO("SMAX", 12, AC_HELI_PID, _slew_rate_max, 0),
|
|
|
|
AP_GROUPEND
|
|
};
|
|
|
|
/// Constructor for PID
|
|
AC_HELI_PID::AC_HELI_PID(float initial_p, float initial_i, float initial_d, float initial_ff, float initial_imax, float initial_filt_T_hz, float initial_filt_E_hz, float initial_filt_D_hz, float dt) :
|
|
AC_PID(initial_p, initial_i, initial_d, initial_ff, initial_imax, initial_filt_T_hz, initial_filt_E_hz, initial_filt_D_hz, dt)
|
|
{
|
|
_last_requested_rate = 0;
|
|
}
|
|
|
|
// This is an integrator which tends to decay to zero naturally
|
|
// if the error is zero.
|
|
|
|
void AC_HELI_PID::update_leaky_i(float leak_rate)
|
|
{
|
|
if(!is_zero(_ki) && !is_zero(_dt)){
|
|
|
|
// integrator does not leak down below Leak Min
|
|
if (_integrator > _leak_min){
|
|
_integrator -= (float)(_integrator - _leak_min) * leak_rate;
|
|
} else if (_integrator < -_leak_min) {
|
|
_integrator -= (float)(_integrator + _leak_min) * leak_rate;
|
|
}
|
|
|
|
_pid_info.I = _integrator;
|
|
}
|
|
}
|