PX4-Autopilot/src/lib/system_identification/system_identification.cpp
2021-10-02 18:12:05 -04:00

102 lines
3.0 KiB
C++

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/**
* @file system_identification.cpp
*
* @author Mathieu Bresciani <mathieu@auterion.com>
*/
#include "system_identification.hpp"
void SystemIdentification::reset(const matrix::Vector<float, 5> &id_state_init)
{
_rls.reset(id_state_init);
_u_lpf.reset(0.f);
_u_lpf.reset(0.f);
_u_hpf = 0.f;
_y_hpf = 0.f;
_u_prev = 0.f;
_y_prev = 0.f;
_fitness_lpf.reset(10.f);
_are_filters_initialized = false;
}
void SystemIdentification::update(float u, float y)
{
updateFilters(u, y);
update();
}
void SystemIdentification::update()
{
_rls.update(_u_hpf, _y_hpf);
updateFitness();
}
void SystemIdentification::updateFilters(float u, float y)
{
if (!_are_filters_initialized) {
_u_lpf.reset(u);
_y_lpf.reset(y);
_u_hpf = 0.f;
_y_hpf = 0.f;
_u_prev = u;
_y_prev = y;
_are_filters_initialized = true;
return;
}
const float u_lpf = _u_lpf.apply(u);
const float y_lpf = _y_lpf.apply(y);
_u_hpf = _alpha_hpf * _u_hpf + _alpha_hpf * (u_lpf - _u_prev);
_y_hpf = _alpha_hpf * _y_hpf + _alpha_hpf * (y_lpf - _y_prev);
_u_prev = u_lpf;
_y_prev = y_lpf;
}
void SystemIdentification::updateFitness()
{
const matrix::Vector<float, 5> &diff = _rls.getDiffEstimate();
float sum = 0.f;
for (size_t i = 0; i < 5; i++) {
sum += diff(i);
}
if (_dt > FLT_EPSILON) {
_fitness_lpf.update(sum / _dt);
}
}