mirror of https://github.com/ArduPilot/ardupilot
90 lines
2.7 KiB
C++
90 lines
2.7 KiB
C++
/// @file AC_P_1D.cpp
|
|
/// @brief Generic P algorithm
|
|
|
|
#include <AP_Math/AP_Math.h>
|
|
#include "AC_P_1D.h"
|
|
|
|
const AP_Param::GroupInfo AC_P_1D::var_info[] = {
|
|
// @Param: P
|
|
// @DisplayName: P Proportional Gain
|
|
// @Description: P Gain which produces an output value that is proportional to the current error value
|
|
AP_GROUPINFO("P", 0, AC_P_1D, _kp, 0),
|
|
AP_GROUPEND
|
|
};
|
|
|
|
// Constructor
|
|
AC_P_1D::AC_P_1D(float initial_p, float dt) :
|
|
_dt(dt)
|
|
{
|
|
// load parameter values from eeprom
|
|
AP_Param::setup_object_defaults(this, var_info);
|
|
|
|
_kp.set_and_default(initial_p);
|
|
}
|
|
|
|
// update_all - set target and measured inputs to P controller and calculate outputs
|
|
// target and measurement are filtered
|
|
float AC_P_1D::update_all(float &target, float measurement)
|
|
{
|
|
// calculate distance _error
|
|
_error = target - measurement;
|
|
|
|
if (is_negative(_error_min) && (_error < _error_min)) {
|
|
_error = _error_min;
|
|
target = measurement + _error;
|
|
} else if (is_positive(_error_max) && (_error > _error_max)) {
|
|
_error = _error_max;
|
|
target = measurement + _error;
|
|
}
|
|
|
|
// MIN(_Dxy_max, _D2xy_max / _kxy_P) limits the max accel to the point where max jerk is exceeded
|
|
return sqrt_controller(_error, _kp, _D1_max, _dt);
|
|
}
|
|
|
|
// set_limits - sets the maximum error to limit output and first and second derivative of output
|
|
// when using for a position controller, lim_err will be position error, lim_out will be correction velocity, lim_D will be acceleration, lim_D2 will be jerk
|
|
void AC_P_1D::set_limits(float output_min, float output_max, float D_Out_max, float D2_Out_max)
|
|
{
|
|
_D1_max = 0.0f;
|
|
_error_min = 0.0f;
|
|
_error_max = 0.0f;
|
|
|
|
if (is_positive(D_Out_max)) {
|
|
_D1_max = D_Out_max;
|
|
}
|
|
|
|
if (is_positive(D2_Out_max) && is_positive(_kp)) {
|
|
// limit the first derivative so as not to exceed the second derivative
|
|
_D1_max = MIN(_D1_max, D2_Out_max / _kp);
|
|
}
|
|
|
|
if (is_negative(output_min) && is_positive(_kp)) {
|
|
_error_min = inv_sqrt_controller(output_min, _kp, _D1_max);
|
|
}
|
|
|
|
if (is_positive(output_max) && is_positive(_kp)) {
|
|
_error_max = inv_sqrt_controller(output_max, _kp, _D1_max);
|
|
}
|
|
}
|
|
|
|
// set_error_limits - reduce maximum error to error_max
|
|
// to be called after setting limits
|
|
void AC_P_1D::set_error_limits(float error_min, float error_max)
|
|
{
|
|
if (is_negative(error_min)) {
|
|
if (!is_zero(_error_min)) {
|
|
_error_min = MAX(_error_min, error_min);
|
|
} else {
|
|
_error_min = error_min;
|
|
}
|
|
}
|
|
|
|
if (is_positive(error_max)) {
|
|
if (!is_zero(_error_max)) {
|
|
_error_max = MIN(_error_max, error_max);
|
|
} else {
|
|
_error_max = error_max;
|
|
}
|
|
}
|
|
}
|