double_diff_drive_controller.h

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/*
 * Author: Enrique Fernández
 */

#include <controller_interface/controller.h>
#include <hardware_interface/joint_command_interface.h>
#include <pluginlib/class_list_macros.hpp>

#include <nav_msgs/Odometry.h>
#include <tf/tfMessage.h>

#include <realtime_tools/realtime_buffer.h>
#include <realtime_tools/realtime_publisher.h>

#include <double_diff_drive_controller/odometry.h>
#include <double_diff_drive_controller/speed_limiter.h>

namespace double_diff_drive_controller
{

class DoubleDiffDriveController: public controller_interface::Controller<hardware_interface::VelocityJointInterface>
{
public:
  DoubleDiffDriveController();

  bool init(hardware_interface::VelocityJointInterface* hw,
            ros::NodeHandle& root_nh,
            ros::NodeHandle& controller_nh);

  void update(const ros::Time& time, const ros::Duration& period);

  void starting(const ros::Time& time);

  void stopping(const ros::Time& time);

private:
  std::string name_;

  ros::Duration publish_period_;
  ros::Time last_state_publish_time_;
  bool open_loop_;

  hardware_interface::JointHandle drive_motor_input_;
  hardware_interface::JointHandle steer_motor_input_;
  // std::vector<hardware_interface::JointHandle> left_wheels_;
  // std::vector<hardware_interface::JointHandle> right_wheels_;

  struct Commands
  {
    double lin;
    double ang;
    ros::Time stamp;

    Commands() : lin(0.0), ang(0.0), stamp(0.0) {}
  };
  realtime_tools::RealtimeBuffer<Commands> command_;
  Commands command_struct_;
  ros::Subscriber sub_command_;

  boost::shared_ptr<realtime_tools::RealtimePublisher<nav_msgs::Odometry> > odom_pub_;
  boost::shared_ptr<realtime_tools::RealtimePublisher<tf::tfMessage> > tf_odom_pub_;
  Odometry odometry_;
  geometry_msgs::TransformStamped odom_frame_;

  double wheel_separation_;

  double drive_motor_gear_ratio_, steer_motor_gear_ratio_;
  double wheel_radius_;

  double wheel_separation_multiplier_;
  double left_wheel_radius_multiplier_;
  double right_wheel_radius_multiplier_;

  double cmd_vel_timeout_;

  std::string base_frame_id_;

  bool enable_odom_tf_;

  size_t wheel_joints_size_;

  // Speed limiters:
  Commands last_cmd_;
  SpeedLimiter limiter_lin_;
  SpeedLimiter limiter_ang_;

private:
  void brake();

  void cmdVelCallback(const geometry_msgs::Twist& command);

  bool setWheelParamsFromUrdf(ros::NodeHandle& root_nh,
                              ros::NodeHandle &controller_nh,
                              const std::string& drive_motor_name,
                              const std::string& steer_motor_name);

  void setupRtPublishersMsg(ros::NodeHandle& root_nh, ros::NodeHandle& controller_nh);

};

PLUGINLIB_EXPORT_CLASS(double_diff_drive_controller::DoubleDiffDriveController, controller_interface::ControllerBase)

} // namespace double_diff_drive_controller