four_wheel_steering_controller.h

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

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

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

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

namespace four_wheel_steering_controller{

  class FourWheelSteeringController
      : public controller_interface::MultiInterfaceController<hardware_interface::VelocityJointInterface,
                                                              hardware_interface::PositionJointInterface>
  {
  public:
    FourWheelSteeringController();

    bool init(hardware_interface::RobotHW* robot_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_;

    std::vector<hardware_interface::JointHandle> front_wheel_joints_;
    std::vector<hardware_interface::JointHandle> rear_wheel_joints_;
    std::vector<hardware_interface::JointHandle> front_steering_joints_;
    std::vector<hardware_interface::JointHandle> rear_steering_joints_;

    struct Command
    {
      ros::Time stamp;

      Command() : stamp(0.0) {}
    };
    struct CommandTwist : Command
    {
      double lin_x;
      double lin_y;
      double ang;

      CommandTwist() : lin_x(0.0), lin_y(0.0), ang(0.0) {}
    };
    struct Command4ws : Command
    {
      double lin;
      double front_steering;
      double rear_steering;

      Command4ws() : lin(0.0), front_steering(0.0), rear_steering(0.0) {}
    };
    realtime_tools::RealtimeBuffer<CommandTwist> command_twist_;
    CommandTwist command_struct_twist_;
    ros::Subscriber sub_command_;

    realtime_tools::RealtimeBuffer<Command4ws> command_four_wheel_steering_;
    Command4ws command_struct_four_wheel_steering_;
    ros::Subscriber sub_command_four_wheel_steering_;

    boost::shared_ptr<realtime_tools::RealtimePublisher<nav_msgs::Odometry> > odom_pub_;
    boost::shared_ptr<realtime_tools::RealtimePublisher<four_wheel_steering_msgs::FourWheelSteeringStamped> > odom_4ws_pub_;
    boost::shared_ptr<realtime_tools::RealtimePublisher<tf::tfMessage> > tf_odom_pub_;
    Odometry odometry_;

    double track_;
    double wheel_steering_y_offset_;

    double wheel_radius_;

    double wheel_base_;

    double cmd_vel_timeout_;

    std::string base_frame_id_;

    bool enable_odom_tf_;

    bool enable_twist_cmd_;

    CommandTwist last1_cmd_;
    CommandTwist last0_cmd_;
    SpeedLimiter limiter_lin_;
    SpeedLimiter limiter_ang_;

  private:

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

    void brake();

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

    void cmdFourWheelSteeringCallback(const four_wheel_steering_msgs::FourWheelSteering &command);

    bool getWheelNames(ros::NodeHandle& controller_nh,
                       const std::string& wheel_param,
                       std::vector<std::string>& wheel_names);

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

  };

  PLUGINLIB_EXPORT_CLASS(four_wheel_steering_controller::FourWheelSteeringController, controller_interface::ControllerBase);
} // namespace four_wheel_steering_controller