mecanum_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.h>

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

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

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

namespace mecanum_drive_controller
{

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

  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 wheel0_jointHandle_;
  hardware_interface::JointHandle wheel1_jointHandle_;
  hardware_interface::JointHandle wheel2_jointHandle_;
  hardware_interface::JointHandle wheel3_jointHandle_;

  struct Commands
  {
    double linX;
    double linY;
    double ang;
    ros::Time stamp;

    Commands() : linX(0.0), linY(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_;

  bool use_realigned_roller_joints_;
  double wheels_k_; // wheels geometric param used in mecanum wheels' ik
  double wheels_radius_;
  double wheel_separation_x_;
  double wheel_separation_y_;

  double cmd_vel_timeout_;

  std::string base_frame_id_;
  std::string odom_frame_id_;

  bool enable_odom_tf_;

  size_t wheel_joints_size_;

  // Speed limiters:
  Commands last_cmd_;
  SpeedLimiter limiter_linX_;
  SpeedLimiter limiter_linY_;
  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& wheel0_name,
                             const std::string& wheel1_name,
                             const std::string& wheel2_name,
                             const std::string& wheel3_name);

  bool getWheelRadius(const urdf::ModelInterfaceSharedPtr model, const urdf::LinkConstSharedPtr& wheel_link, double& wheel_radius);

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

};

PLUGINLIB_EXPORT_CLASS(mecanum_drive_controller::MecanumDriveController, controller_interface::ControllerBase)

} // namespace mecanum_drive_controller