PID_Controller.h

/*+-------------------------------------------------------------------------+
  |                       MultiVehicle simulator (libmvsim)                 |
  |                                                                         |
  | Copyright (C) 2014-2026  Jose Luis Blanco Claraco                       |
  | Copyright (C) 2017  Borys Tymchenko (Odessa Polytechnic University)     |
  | Distributed under 3-clause BSD License                                  |
  |   See COPYING                                                           |
  +-------------------------------------------------------------------------+ */
#pragma once
 
namespace mvsim
{
struct PID_Controller
{
    PID_Controller() = default;
 
    double KP = 1.0, KI = 0, KD = 0;
 
    double N = 0;
 
    double max_out = 0;  
 
    bool enable_antiwindup = false;
 
    bool enable_reference_filter = false;
 
    double reference_filter_tau = 0.1;
 
    int reference_filter_order = 1;
 
    double compute(double err, double dt, double feedforward = 0);
 
    double filterReference(double setpoint, double dt);
 
    void reset();
 
   private:
    double lastOutput_ = 0;
    double i_state_ = 0;  
    double d_state_ = 0;  
    double e_prev_ = 0;  
    double refFilter_y1_ = 0;  
    double refFilter_y2_ = 0;  
    bool firstCall_ = true;
};
}  // namespace mvsim