pid.h

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#ifndef CONTROL_TOOLBOX_PID_H
#define CONTROL_TOOLBOX_PID_H


#include <string>
#include "ros/node_handle.h"

class TiXmlElement;

namespace control_toolbox {

/***************************************************/
/***************************************************/

class Pid
{
public:

  Pid(double P = 0.0, double I = 0.0, double D = 0.0, double I1 = 0.0, double I2 = -0.0);

  ~Pid();

  double updatePid(double p_error, ros::Duration dt);

  void initPid(double P, double I, double D, double I1, double I2);
  
  bool initParam(const std::string& prefix);
  bool initXml(TiXmlElement *config);
  bool init(const ros::NodeHandle &n);

  void reset();

  void setCurrentCmd(double cmd);

  double getCurrentCmd();

  void getCurrentPIDErrors(double *pe, double *ie, double *de);

  void setGains(double P, double I, double D, double i_max, double i_min);

  void getGains(double &p, double &i, double &d, double &i_max, double &i_min);

  double updatePid(double error, double error_dot, ros::Duration dt);

  Pid &operator =(const Pid& p)
  {
    if (this == &p)
      return *this;

    p_gain_ = p.p_gain_;
    i_gain_ = p.i_gain_;
    d_gain_ = p.d_gain_;
    i_max_ = p.i_max_;
    i_min_ = p.i_min_;

    p_error_last_ = p_error_ = i_error_ = d_error_ = cmd_ = 0.0;
    return *this;
  }

private:
  double p_error_last_; 
  double p_error_; 
  double d_error_; 
  double i_error_; 
  double p_gain_;  
  double i_gain_;  
  double d_gain_;  
  double i_max_;   
  double i_min_;   
  double cmd_;     
};

}

#endif