pid.h

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#ifndef ROBOT_CONTROLLERS_PID_H
#define ROBOT_CONTROLLERS_PID_H

#include <ros/ros.h>

namespace robot_controllers
{

class PID
{
public:
  PID(double p, double i, double d, double i_max, double i_min);

  PID();

  bool init(const ros::NodeHandle &nh);

  void reset();

  double update(double error, double dt);

  double update(double error, double error_dot, double dt);

protected:

  bool checkGains();

  double p_gain_;
  double i_gain_;
  double d_gain_;
  double i_max_, i_min_;

  double i_term_; 

  double error_last_;
};

}  // namespace robot_controllers

#endif  // ROBOT_CONTROLLERS_PID_H