diffdrive_plugin_6w.h

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//=================================================================================================
// Copyright (c) 2011, Stefan Kohlbrecher, TU Darmstadt
// All rights reserved.

// Redistribution and use in source and binary forms, with or without
// modification, are permitted provided that the following conditions are met:
//     * Redistributions of source code must retain the above copyright
//       notice, this list of conditions and the following disclaimer.
//     * Redistributions in binary form must reproduce the above copyright
//       notice, this list of conditions and the following disclaimer in the
//       documentation and/or other materials provided with the distribution.
//     * Neither the name of the Simulation, Systems Optimization and Robotics
//       group, TU Darmstadt nor the names of its contributors may be used to
//       endorse or promote products derived from this software without
//       specific prior written permission.

// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" AND
// ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
// WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
// DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER BE LIABLE FOR ANY
// DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
// (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
// LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
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// (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
// SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
//=================================================================================================
/*
 * Desc: ROS interface to a Position2d controller for a Differential drive.
 * Author: Daniel Hewlett (adapted from Nathan Koenig)
 */
#ifndef DIFFDRIVE_PLUGIN_HH
#define DIFFDRIVE_PLUGIN_HH

#include <map>

#include <gazebo/common/Plugin.hh>
#include <gazebo/common/Time.hh>

// ROS 
#include <ros/ros.h>
#include <tf/transform_broadcaster.h>
#include <tf/transform_listener.h>
#include <geometry_msgs/Twist.h>
#include <nav_msgs/Odometry.h>

// Custom Callback Queue
#include <ros/callback_queue.h>
#include <ros/advertise_options.h>

// Boost
#include <boost/thread.hpp>
#include <boost/bind.hpp>

namespace gazebo
{

class DiffDrivePlugin6W : public ModelPlugin
{

public:
  DiffDrivePlugin6W();
  virtual ~DiffDrivePlugin6W();

protected:
  virtual void Load(physics::ModelPtr _model, sdf::ElementPtr _sdf);
  virtual void Reset();
  virtual void Update();

private:
  void publish_odometry();
  void GetPositionCmd();

  physics::LinkPtr link;
  physics::WorldPtr world;
  physics::JointPtr joints[6];

  float wheelSep;
  float wheelDiam;
  float torque;
  float wheelSpeed[2];

  // Simulation time of the last update
  common::Time prevUpdateTime;

  bool enableMotors;
  float odomPose[3];
  float odomVel[3];

  // ROS STUFF
  ros::NodeHandle* rosnode_;
  ros::Publisher pub_;
  ros::Subscriber sub_;
  tf::TransformBroadcaster *transform_broadcaster_;
  nav_msgs::Odometry odom_;
  std::string tf_prefix_;

  boost::mutex lock;

  std::string namespace_;
  std::string topic_;
  std::string link_name_;

  // Custom Callback Queue
  ros::CallbackQueue queue_;
  boost::thread callback_queue_thread_;
  void QueueThread();

  // DiffDrive stuff
  void cmdVelCallback(const geometry_msgs::Twist::ConstPtr& cmd_msg);

  float x_;
  float rot_;
  bool alive_;

  // Pointer to the update event connection
  event::ConnectionPtr updateConnection;
};

}

#endif