pid_ros.hpp

// Copyright (c) 2020, Open Source Robotics Foundation, Inc.
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#ifndef CONTROL_TOOLBOX__PID_ROS_HPP_
#define CONTROL_TOOLBOX__PID_ROS_HPP_
 
#include <memory>
#include <string>
 
#include "control_msgs/msg/pid_state.hpp"
 
#include "rclcpp/clock.hpp"
#include "rclcpp/duration.hpp"
#include "rclcpp/node.hpp"
 
#include "realtime_tools/realtime_publisher.hpp"
 
#include "control_toolbox/pid.hpp"
 
namespace control_toolbox
{
 
class PidROS
{
public:
  template <class NodeT>
  explicit PidROS(
    std::shared_ptr<NodeT> node_ptr, const std::string & param_prefix,
    const std::string & topic_prefix)
  : PidROS(
      node_ptr->get_node_base_interface(), node_ptr->get_node_logging_interface(),
      node_ptr->get_node_parameters_interface(), node_ptr->get_node_topics_interface(),
      param_prefix, topic_prefix, !topic_prefix.empty())
  {
  }
 
  template <class NodeT>
  explicit PidROS(
    std::shared_ptr<NodeT> node_ptr, const std::string & param_prefix,
    const std::string & topic_prefix, bool activate_state_publisher)
  : PidROS(
      node_ptr->get_node_base_interface(), node_ptr->get_node_logging_interface(),
      node_ptr->get_node_parameters_interface(), node_ptr->get_node_topics_interface(),
      param_prefix, topic_prefix, activate_state_publisher)
  {
  }
 
  PidROS(
    rclcpp::node_interfaces::NodeBaseInterface::SharedPtr node_base,
    rclcpp::node_interfaces::NodeLoggingInterface::SharedPtr node_logging,
    rclcpp::node_interfaces::NodeParametersInterface::SharedPtr node_params,
    rclcpp::node_interfaces::NodeTopicsInterface::SharedPtr topics_interface,
    const std::string & param_prefix, const std::string & topic_prefix,
    bool activate_state_publisher);
 
  bool initialize_from_args(
    double p, double i, double d, double u_max, double u_min,
    const AntiWindupStrategy & antiwindup_strat, bool save_i_term);
 
  bool initialize_from_ros_parameters();
 
  void reset();
 
  void reset(bool save_i_term);
 
  double compute_command(double error, const rclcpp::Duration & dt);
 
  double compute_command(double error, double error_dot, const rclcpp::Duration & dt);
 
  Pid::Gains get_gains();
 
  bool set_gains(
    double p, double i, double d, double u_max, double u_min,
    const AntiWindupStrategy & antiwindup_strat);
 
  bool set_gains(const Pid::Gains & gains);
 
  void set_current_cmd(double cmd);
 
  double get_current_cmd();
 
  void get_current_pid_errors(double & pe, double & ie, double & de);
 
  void print_values();
 
  inline rclcpp::node_interfaces::OnSetParametersCallbackHandle::SharedPtr
  get_parameters_callback_handle()
  {
    return parameter_callback_;
  }
 
protected:
  std::string topic_prefix_;
  std::string param_prefix_;
 
private:
  void set_parameter_event_callback();
 
  void publish_pid_state(double cmd, double error, rclcpp::Duration dt);
 
  void declare_param(const std::string & param_name, rclcpp::ParameterValue param_value);
 
  bool get_double_param(const std::string & param_name, double & value);
 
  bool get_boolean_param(const std::string & param_name, bool & value);
 
  bool get_string_param(const std::string & param_name, std::string & value);
 
  rclcpp::node_interfaces::OnSetParametersCallbackHandle::SharedPtr parameter_callback_;
 
  rclcpp::node_interfaces::NodeBaseInterface::SharedPtr node_base_;
  rclcpp::node_interfaces::NodeLoggingInterface::SharedPtr node_logging_;
  rclcpp::node_interfaces::NodeParametersInterface::SharedPtr node_params_;
  rclcpp::node_interfaces::NodeTopicsInterface::SharedPtr topics_interface_;
 
  std::shared_ptr<realtime_tools::RealtimePublisher<control_msgs::msg::PidState>> rt_state_pub_;
  control_msgs::msg::PidState pid_state_msg_;
 
  Pid pid_;
};
 
}  // namespace control_toolbox
 
#endif  // CONTROL_TOOLBOX__PID_ROS_HPP_