pid.h

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#ifndef CONTROL_TOOLBOX_PID_H
#define CONTROL_TOOLBOX_PID_H


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

// Dynamic reconfigure
#include <dynamic_reconfigure/server.h>
#include <control_toolbox/ParametersConfig.h>
#include <boost/thread/mutex.hpp>

// Realtime buffer
#include <realtime_tools/realtime_buffer.h>

class TiXmlElement;

namespace control_toolbox {

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

class Pid
{
public:

  struct Gains 
  {
    // Optional constructor for passing in values
    Gains(double p, double i, double d, double i_max, double i_min) 
      : p_gain_(p),
        i_gain_(i),
        d_gain_(d),
        i_max_(i_max),
        i_min_(i_min)
    {}
    // Default constructor
    Gains() {}
    double p_gain_;  
    double i_gain_;  
    double d_gain_;  
    double i_max_;   
    double i_min_;   
  };

  Pid(double p = 0.0, double i = 0.0, double d = 0.0, double i_max = 0.0, double i_min = -0.0);

  Pid(const Pid &source);

  ~Pid();

  void initPid(double p, double i, double d, double i_max, double i_min);

  void initPid(double p, double i, double d, double i_max, double i_min, const ros::NodeHandle &node);

  bool initParam(const std::string& prefix);

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

  bool initXml(TiXmlElement *config);

  void initDynamicReconfig(ros::NodeHandle &node);

  void reset();

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

  Gains getGains();

  void setGains(double p, double i, double d, double i_max, double i_min);

  void setGains(const Gains &gains);

  void updateDynamicReconfig();
  void updateDynamicReconfig(Gains gains_config);
  void updateDynamicReconfig(control_toolbox::ParametersConfig config);

  void dynamicReconfigCallback(control_toolbox::ParametersConfig &config, uint32_t level);

  double computeCommand(double error, ros::Duration dt);

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

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

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

  void setCurrentCmd(double cmd);

  double getCurrentCmd();

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

  
  void printValues();

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

    // Copy the realtime buffer to then new PID class
    gains_buffer_ = source.gains_buffer_;
    
    // Reset the state of this PID controller
    reset();

    return *this;
  }

private:

  // Store the PID gains in a realtime buffer to allow dynamic reconfigure to update it without
  // blocking the realtime update loop
  realtime_tools::RealtimeBuffer<Gains> gains_buffer_; 

  double p_error_last_; 
  double p_error_; 
  double d_error_; 
  double i_term_;  
  double cmd_;     
  // Dynamics reconfigure
  bool dynamic_reconfig_initialized_;
  typedef dynamic_reconfigure::Server<control_toolbox::ParametersConfig> DynamicReconfigServer;                             
  boost::shared_ptr<DynamicReconfigServer> param_reconfig_server_;
  DynamicReconfigServer::CallbackType param_reconfig_callback_;

  boost::recursive_mutex param_reconfig_mutex_;

};

}

#endif