cob_base_drive_chain.cpp

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/****************************************************************
 *
 * Copyright (c) 2010
 *
 * Fraunhofer Institute for Manufacturing Engineering   
 * and Automation (IPA)
 *
 * +++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
 *
 * Project name: care-o-bot
 * ROS stack name: cob_driver
 * ROS package name: cob_base_drive_chain
 * Description: This node provides control of the care-o-bot platform drives to the ROS-"network". For this purpose it offers several services and publishes data on different topics.
 *                                                              
 * +++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
 *                      
 * Author: Christian Connette, email:christian.connette@ipa.fhg.de
 * Supervised by: Christian Connette, email:christian.connette@ipa.fhg.de
 *
 * Date of creation: Feb 2010:
 * ToDo: Doesn't this node has to take care about the Watchdogs?
 *
 * +++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
 *
 * 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 Fraunhofer Institute for Manufacturing 
 *         Engineering and Automation (IPA) nor the names of its
 *         contributors may be used to endorse or promote products derived from
 *         this software without specific prior written permission.
 *
 * This program is free software: you can redistribute it and/or modify
 * it under the terms of the GNU Lesser General Public License LGPL as 
 * published by the Free Software Foundation, either version 3 of the 
 * License, or (at your option) any later version.
 * 
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU Lesser General Public License LGPL for more details.
 * 
 * You should have received a copy of the GNU Lesser General Public 
 * License LGPL along with this program. 
 * If not, see <http://www.gnu.org/licenses/>.
 *
 ****************************************************************/

//##################
//#### includes ####

// standard includes
//--

// ROS includes
#include <ros/ros.h>

// ROS message includes
#include <std_msgs/Float64.h>
#include <sensor_msgs/JointState.h>
#include <diagnostic_msgs/DiagnosticStatus.h>
#include <diagnostic_msgs/DiagnosticArray.h>
#include <pr2_controllers_msgs/JointTrajectoryControllerState.h>
#include <pr2_controllers_msgs/JointControllerState.h>

// ROS service includes
#include <cob_srvs/Trigger.h>
#include <cob_base_drive_chain/ElmoRecorderReadout.h>
#include <cob_base_drive_chain/ElmoRecorderConfig.h>


// external includes
#include <cob_base_drive_chain/CanCtrlPltfCOb3.h>
#include <cob_utilities/IniFile.h>
#include <cob_utilities/MathSup.h>

//####################
//#### node class ####
class NodeClass
{
        public:
                // create a handle for this node, initialize node
                ros::NodeHandle n;

                // topics to publish
                ros::Publisher topicPub_JointState;

                ros::Publisher topicPub_ControllerState;
                ros::Publisher topicPub_DiagnosticGlobal_;


                ros::Publisher topicPub_Diagnostic;


                // topics to subscribe, callback is called for new messages arriving
                ros::Subscriber topicSub_JointStateCmd;

                // service servers
                ros::ServiceServer srvServer_Init;

                ros::ServiceServer srvServer_Recover;

                ros::ServiceServer srvServer_Shutdown;

                ros::ServiceServer srvServer_SetMotionType;

                ros::ServiceServer srvServer_ElmoRecorderConfig;

                ros::ServiceServer srvServer_ElmoRecorderReadout;

                // global variables
                // generate can-node handle
#ifdef __SIM__
                ros::Publisher br_steer_pub;
                ros::Publisher bl_steer_pub;
                ros::Publisher fr_steer_pub;
                ros::Publisher fl_steer_pub;
                ros::Publisher br_caster_pub;
                ros::Publisher bl_caster_pub;
                ros::Publisher fr_caster_pub;
                ros::Publisher fl_caster_pub;
                
                std::vector<double> m_gazeboPos;
                std::vector<double> m_gazeboVel;
                ros::Time m_gazeboStamp;

                ros::Subscriber topicSub_GazeboJointStates;
#else
                CanCtrlPltfCOb3 *m_CanCtrlPltf;
#endif
                bool m_bisInitialized;
                int m_iNumMotors;
                int m_iNumDrives;

                struct ParamType
                { 
                        double dMaxDriveRateRadpS;
                        double dMaxSteerRateRadpS;

                        std::vector<double> vdWheelNtrlPosRad;
                };
                ParamType m_Param;
                
                std::string sIniDirectory;
                bool m_bPubEffort;
                bool m_bReadoutElmo;

                // Constructor
                NodeClass()
                {
                        // Read number of drives from iniFile and pass IniDirectory to CobPlatfCtrl.
                        if (n.hasParam("IniDirectory"))
                        {
                                n.getParam("IniDirectory", sIniDirectory);
                                ROS_INFO("IniDirectory loaded from Parameter-Server is: %s", sIniDirectory.c_str());
                        }
                        else
                        {
                                sIniDirectory = "Platform/IniFiles/";
                                ROS_WARN("IniDirectory not found on Parameter-Server, using default value: %s", sIniDirectory.c_str());
                        }

                        n.param<bool>("PublishEffort", m_bPubEffort, false);
                        if(m_bPubEffort) ROS_INFO("You have choosen to publish effort of motors, that charges capacity of CAN");
                        
                        
                        IniFile iniFile;
                        iniFile.SetFileName(sIniDirectory + "Platform.ini", "PltfHardwareCoB3.h");

                        // get max Joint-Velocities (in rad/s) for Steer- and Drive-Joint
                        iniFile.GetKeyInt("Config", "NumberOfMotors", &m_iNumMotors, true);
                        iniFile.GetKeyInt("Config", "NumberOfWheels", &m_iNumDrives, true);
                        if(m_iNumMotors < 2 || m_iNumMotors > 8) {
                                m_iNumMotors = 8;
                                m_iNumDrives = 4;
                        }
                        
#ifdef __SIM__
                        bl_caster_pub = n.advertise<std_msgs::Float64>("/base_bl_caster_r_wheel_controller/command", 1);
                        br_caster_pub = n.advertise<std_msgs::Float64>("/base_br_caster_r_wheel_controller/command", 1);
                        fl_caster_pub = n.advertise<std_msgs::Float64>("/base_fl_caster_r_wheel_controller/command", 1);
                        fr_caster_pub = n.advertise<std_msgs::Float64>("/base_fr_caster_r_wheel_controller/command", 1);
                        bl_steer_pub = n.advertise<std_msgs::Float64>("/base_bl_caster_rotation_controller/command", 1);
                        br_steer_pub = n.advertise<std_msgs::Float64>("/base_br_caster_rotation_controller/command", 1);
                        fl_steer_pub = n.advertise<std_msgs::Float64>("/base_fl_caster_rotation_controller/command", 1);
                        fr_steer_pub = n.advertise<std_msgs::Float64>("/base_fr_caster_rotation_controller/command", 1);

                        topicSub_GazeboJointStates = n.subscribe("/joint_states", 1, &NodeClass::gazebo_joint_states_Callback, this);
                        
                        m_gazeboPos.resize(m_iNumMotors);
                        m_gazeboVel.resize(m_iNumMotors);
#else
                        m_CanCtrlPltf = new CanCtrlPltfCOb3(sIniDirectory);
#endif
                        
                        // implementation of topics
                        // published topics
                        topicPub_JointState = n.advertise<sensor_msgs::JointState>("/joint_states", 1);
                        topicPub_ControllerState = n.advertise<pr2_controllers_msgs::JointTrajectoryControllerState>("state", 1);
                        topicPub_DiagnosticGlobal_ = n.advertise<diagnostic_msgs::DiagnosticArray>("/diagnostics", 1);
                        
                        topicPub_Diagnostic = n.advertise<diagnostic_msgs::DiagnosticStatus>("diagnostic", 1);
                        // subscribed topics
                        topicSub_JointStateCmd = n.subscribe("joint_command", 1, &NodeClass::topicCallback_JointStateCmd, this);

                        // implementation of service servers
                        srvServer_Init = n.advertiseService("init", &NodeClass::srvCallback_Init, this);
                        srvServer_ElmoRecorderConfig = n.advertiseService("ElmoRecorderConfig", &NodeClass::srvCallback_ElmoRecorderConfig, this);
                        srvServer_ElmoRecorderReadout = n.advertiseService("ElmoRecorderReadout", &NodeClass::srvCallback_ElmoRecorderReadout, this);
                        m_bReadoutElmo = false;

                        srvServer_Recover = n.advertiseService("recover", &NodeClass::srvCallback_Recover, this);
                        srvServer_Shutdown = n.advertiseService("shutdown", &NodeClass::srvCallback_Shutdown, this);
                        
                        // initialization of variables
#ifdef __SIM__
                        m_bisInitialized = initDrives();
#else
                        m_bisInitialized = false;
#endif

                }

                // Destructor
                ~NodeClass() 
                {
#ifdef __SIM__

#else
                        m_CanCtrlPltf->shutdownPltf();
#endif
                }

                // topic callback functions 
                // function will be called when a new message arrives on a topic
                void topicCallback_JointStateCmd(const pr2_controllers_msgs::JointTrajectoryControllerState::ConstPtr& msg)
                {
                        ROS_DEBUG("Topic Callback joint_command");
                        // only process cmds when system is initialized
                        if(m_bisInitialized == true)
                        {
                                ROS_DEBUG("Topic Callback joint_command - Sending Commands to drives (initialized)");
                                sensor_msgs::JointState JointStateCmd;
                                JointStateCmd.position.resize(m_iNumMotors);
                                JointStateCmd.velocity.resize(m_iNumMotors);
                                JointStateCmd.effort.resize(m_iNumMotors);
                                
                                for(unsigned int i = 0; i < msg->joint_names.size(); i++)
                                {
                                        // associate inputs to according steer and drive joints
                                        // ToDo: specify this globally (Prms-File or config-File or via msg-def.)
                                        // check if velocities lie inside allowed boundaries
                                        
                                        //DRIVES
                                        if(msg->joint_names[i] ==  "fl_caster_r_wheel_joint")
                                        {
                                                        JointStateCmd.position[0] = msg->desired.positions[i];
                                                        JointStateCmd.velocity[0] = msg->desired.velocities[i];
                                                        //JointStateCmd.effort[0] = msg->effort[i];
                                        }
                                        else if(m_iNumDrives>=2 && msg->joint_names[i] ==  "bl_caster_r_wheel_joint")
                                        {
                                                        JointStateCmd.position[2] = msg->desired.positions[i];
                                                        JointStateCmd.velocity[2] = msg->desired.velocities[i];
                                                        //JointStateCmd.effort[2] = msg->effort[i];
                                        }
                                        else if(m_iNumDrives>=3 && msg->joint_names[i] ==  "br_caster_r_wheel_joint")
                                        {
                                                        JointStateCmd.position[4] = msg->desired.positions[i];
                                                        JointStateCmd.velocity[4] = msg->desired.velocities[i];
                                                        //JointStateCmd.effort[4] = msg->effort[i];
                                        }
                                        else if(m_iNumDrives>=4 && msg->joint_names[i] ==  "fr_caster_r_wheel_joint")
                                        {
                                                        JointStateCmd.position[6] = msg->desired.positions[i];
                                                        JointStateCmd.velocity[6] = msg->desired.velocities[i];
                                                        //JointStateCmd.effort[6] = msg->effort[i];
                                        }
                                        //STEERS
                                        else if(msg->joint_names[i] ==  "fl_caster_rotation_joint")
                                        {
                                                        JointStateCmd.position[1] = msg->desired.positions[i];
                                                        JointStateCmd.velocity[1] = msg->desired.velocities[i];
                                                        //JointStateCmd.effort[1] = msg->effort[i];
                                        }
                                        else if(m_iNumDrives>=2 && msg->joint_names[i] ==  "bl_caster_rotation_joint")
                                        { 
                                                        JointStateCmd.position[3] = msg->desired.positions[i];
                                                        JointStateCmd.velocity[3] = msg->desired.velocities[i];
                                                        //JointStateCmd.effort[3] = msg->effort[i];
                                        }
                                        else if(m_iNumDrives>=3 && msg->joint_names[i] ==  "br_caster_rotation_joint")
                                        {
                                                        JointStateCmd.position[5] = msg->desired.positions[i];
                                                        JointStateCmd.velocity[5] = msg->desired.velocities[i];
                                                        //JointStateCmd.effort[5] = msg->effort[i];
                                        }
                                        else if(m_iNumDrives>=4 && msg->joint_names[i] ==  "fr_caster_rotation_joint")
                                        {
                                                        JointStateCmd.position[7] = msg->desired.positions[i];
                                                        JointStateCmd.velocity[7] = msg->desired.velocities[i];
                                                        //JointStateCmd.effort[7] = msg->effort[i];
                                        }
                                        else
                                        {
                                                ROS_ERROR("Unkown joint name");
                                        }
                                }
                                
                        
                                // check if velocities lie inside allowed boundaries
                                for(int i = 0; i < m_iNumMotors; i++)
                                {
#ifdef __SIM__
#else   
                                        // for steering motors
                                        if( i == 1 || i == 3 || i == 5 || i == 7) // ToDo: specify this via the config-files
                                        {
                                                if (JointStateCmd.velocity[i] > m_Param.dMaxSteerRateRadpS)
                                                {
                                                        JointStateCmd.velocity[i] = m_Param.dMaxSteerRateRadpS;
                                                }
                                                if (JointStateCmd.velocity[i] < -m_Param.dMaxSteerRateRadpS)
                                                {
                                                        JointStateCmd.velocity[i] = -m_Param.dMaxSteerRateRadpS;
                                                }
                                        }
                                        // for driving motors
                                        else
                                        {
                                                if (JointStateCmd.velocity[i] > m_Param.dMaxDriveRateRadpS)
                                                {
                                                        JointStateCmd.velocity[i] = m_Param.dMaxDriveRateRadpS;
                                                }
                                                if (JointStateCmd.velocity[i] < -m_Param.dMaxDriveRateRadpS)
                                                {
                                                        JointStateCmd.velocity[i] = -m_Param.dMaxDriveRateRadpS;
                                                }
                                        }
#endif
#ifdef __SIM__
                                        ROS_DEBUG("Send velocity data to gazebo");
                                        std_msgs::Float64 fl;
                                        fl.data = JointStateCmd.velocity[i];
                                        if(msg->joint_names[i] == "fl_caster_r_wheel_joint")
                                                fl_caster_pub.publish(fl);
                                        if(msg->joint_names[i] == "fr_caster_r_wheel_joint")
                                                fr_caster_pub.publish(fl);
                                        if(msg->joint_names[i] == "bl_caster_r_wheel_joint")
                                                bl_caster_pub.publish(fl);
                                        if(msg->joint_names[i] == "br_caster_r_wheel_joint")
                                                br_caster_pub.publish(fl);

                                        if(msg->joint_names[i] == "fl_caster_rotation_joint")
                                                fl_steer_pub.publish(fl);
                                        if(msg->joint_names[i] == "fr_caster_rotation_joint")
                                                fr_steer_pub.publish(fl);
                                        if(msg->joint_names[i] == "bl_caster_rotation_joint")
                                                bl_steer_pub.publish(fl);
                                        if(msg->joint_names[i] == "br_caster_rotation_joint")
                                                br_steer_pub.publish(fl);
                                        ROS_DEBUG("Successfully sent velicities to gazebo");
#else
                                        ROS_DEBUG("Send velocity data to drives");
                                        m_CanCtrlPltf->setVelGearRadS(i, JointStateCmd.velocity[i]);
                                        ROS_DEBUG("Successfully sent velicities to drives");
#endif
                                }       
                                        
#ifdef __SIM__

#else
                                if(m_bPubEffort) {
                                        m_CanCtrlPltf->requestMotorTorque();
                                }
#endif
                        }
                }

                // service callback functions
                // function will be called when a service is querried

                // Init Can-Configuration
                bool srvCallback_Init(cob_srvs::Trigger::Request &req,
                                                          cob_srvs::Trigger::Response &res )
                {
                        ROS_DEBUG("Service Callback init");
                        if(m_bisInitialized == false)
                        {
                                m_bisInitialized = initDrives();
                                //ROS_INFO("...initializing can-nodes...");
                                //m_bisInitialized = m_CanCtrlPltf->initPltf();
                                res.success.data = m_bisInitialized;
                                if(m_bisInitialized)
                                {
                                        ROS_INFO("base initialized");
                                }
                                else
                                {
                                        res.error_message.data = "initialization of base failed";
                                        ROS_ERROR("Initializing base failed");
                                }
                        }
                        else
                        {
                                ROS_WARN("...base already initialized...");
                                res.success.data = true;
                                res.error_message.data = "platform already initialized";
                        }
                        return true;
                }
                
                bool srvCallback_ElmoRecorderConfig(cob_base_drive_chain::ElmoRecorderConfig::Request &req,
                                                          cob_base_drive_chain::ElmoRecorderConfig::Response &res ){
                        if(m_bisInitialized) 
                        {
#ifdef __SIM__
                                res.success = true;
#else
                                m_CanCtrlPltf->evalCanBuffer();
                                res.success = m_CanCtrlPltf->ElmoRecordings(0, req.recordinggap, "");
#endif
                                res.message = "Successfully configured all motors for instant record";
                        }

                        return true;
                }
                
                bool srvCallback_ElmoRecorderReadout(cob_base_drive_chain::ElmoRecorderReadout::Request &req,
                                                          cob_base_drive_chain::ElmoRecorderReadout::Response &res ){
                        if(m_bisInitialized) {
#ifdef __SIM__
                                res.success = true;
#else
                                m_CanCtrlPltf->evalCanBuffer();
                                res.success = m_CanCtrlPltf->ElmoRecordings(1, req.subindex, req.fileprefix);
#endif
                                if(res.success == 0) {
                                        res.message = "Successfully requested reading out of Recorded data";
                                        m_bReadoutElmo = true;
                                        ROS_WARN("CPU consuming evalCanBuffer used for ElmoReadout activated");
                                } else if(res.success == 1) res.message = "Recorder hasn't been configured well yet";
                                else if(res.success == 2) res.message = "A previous transmission is still in progress";
                        }

                        return true;
                }
                
                
                
                // reset Can-Configuration
                bool srvCallback_Recover(cob_srvs::Trigger::Request &req,
                                                                         cob_srvs::Trigger::Response &res )
                {
                        if(m_bisInitialized)
                        {
                                ROS_DEBUG("Service callback reset");
#ifdef __SIM__
                                res.success.data = true;
#else
                                res.success.data = m_CanCtrlPltf->resetPltf();
#endif
                                if (res.success.data) {
                                        ROS_INFO("base resetted");
                                } else {
                                        res.error_message.data = "reset of base failed";
                                        ROS_WARN("Resetting base failed");
                                }
                        }
                        else
                        {
                                ROS_WARN("...base already recovered...");
                                res.success.data = true;
                                res.error_message.data = "base already recovered";
                        }

                        return true;
                }
                
                // shutdown Drivers and Can-Node
                bool srvCallback_Shutdown(cob_srvs::Trigger::Request &req,
                                                                         cob_srvs::Trigger::Response &res )
                {
                        ROS_DEBUG("Service callback shutdown");
#ifdef __SIM__
                        res.success.data = true;
#else
                        res.success.data = m_CanCtrlPltf->shutdownPltf();
#endif
                        if (res.success.data)
                                ROS_INFO("Drives shut down");
                        else
                                ROS_INFO("Shutdown of Drives FAILED");

                        return true;
                }

                //publish JointStates cyclical instead of service callback
                bool publish_JointStates()
                {
                        // init local variables
                        int j, k;
                        bool bIsError;
                        std::vector<double> vdAngGearRad, vdVelGearRad, vdEffortGearNM;

                        // set default values
                        vdAngGearRad.resize(m_iNumMotors, 0);
                        vdVelGearRad.resize(m_iNumMotors, 0);
                        vdEffortGearNM.resize(m_iNumMotors, 0);

                        // create temporary (local) JointState/Diagnostics Data-Container
                        sensor_msgs::JointState jointstate;
                        diagnostic_msgs::DiagnosticStatus diagnostics;
                        pr2_controllers_msgs::JointTrajectoryControllerState controller_state;
                        
                        // get time stamp for header
#ifdef __SIM__
                        jointstate.header.stamp = m_gazeboStamp;
                        controller_state.header.stamp = m_gazeboStamp;
#else
                        jointstate.header.stamp = ros::Time::now();
                        controller_state.header.stamp = jointstate.header.stamp;
#endif

                        // assign right size to JointState
                        //jointstate.name.resize(m_iNumMotors);
                        jointstate.position.assign(m_iNumMotors, 0.0);
                        jointstate.velocity.assign(m_iNumMotors, 0.0);
                        jointstate.effort.assign(m_iNumMotors, 0.0);

                        if(m_bisInitialized == false)
                        {
                                // as long as system is not initialized
                                bIsError = false;

                                j = 0;
                                k = 0;

                                // set data to jointstate                       
                                for(int i = 0; i<m_iNumMotors; i++)
                                {
                                        jointstate.position[i] = 0.0;
                                        jointstate.velocity[i] = 0.0;
                                        jointstate.effort[i] = 0.0;
                                }
                                jointstate.name.push_back("fl_caster_r_wheel_joint");
                                jointstate.name.push_back("fl_caster_rotation_joint");
                                jointstate.name.push_back("bl_caster_r_wheel_joint");
                                jointstate.name.push_back("bl_caster_rotation_joint");
                                jointstate.name.push_back("br_caster_r_wheel_joint");
                                jointstate.name.push_back("br_caster_rotation_joint");
                                jointstate.name.push_back("fr_caster_r_wheel_joint");
                                jointstate.name.push_back("fr_caster_rotation_joint");
                        
                        }
                        else
                        {
                                // as soon as drive chain is initialized
                                // read Can-Buffer
#ifdef __SIM__

#else
                                ROS_DEBUG("Read CAN-Buffer");
                                m_CanCtrlPltf->evalCanBuffer();
                                ROS_DEBUG("Successfully read CAN-Buffer");
#endif
                                j = 0;
                                k = 0;
                                for(int i = 0; i<m_iNumMotors; i++)
                                {
#ifdef __SIM__
                                        vdAngGearRad[i] = m_gazeboPos[i];
                                        vdVelGearRad[i] = m_gazeboVel[i];
#else
                                        m_CanCtrlPltf->getGearPosVelRadS(i,  &vdAngGearRad[i], &vdVelGearRad[i]);
#endif
                                        
                                        //Get motor torque
                                        if(m_bPubEffort) {
                                                for(int i=0; i<m_iNumMotors; i++) 
                                                {
#ifdef __SIM__
                                                        //vdEffortGearNM[i] = m_gazeboEff[i];
#else
                                                        m_CanCtrlPltf->getMotorTorque(i, &vdEffortGearNM[i]); //(int iCanIdent, double* pdTorqueNm)
#endif
                                                }
                                        }

                                        // if a steering motor was read -> correct for offset
                                        if( i == 1 || i == 3 || i == 5 || i == 7) // ToDo: specify this via the config-files
                                        {
                                                // correct for initial offset of steering angle (arbitrary homing position)
                                                vdAngGearRad[i] += m_Param.vdWheelNtrlPosRad[j];
                                                MathSup::normalizePi(vdAngGearRad[i]);
                                                j = j+1;
                                        }
                                }

                                // set data to jointstate
                                for(int i = 0; i<m_iNumMotors; i++)
                                {
                                        jointstate.position[i] = vdAngGearRad[i];
                                        jointstate.velocity[i] = vdVelGearRad[i];
                                        jointstate.effort[i] = vdEffortGearNM[i];
                                }
                                
                                jointstate.name.push_back("fl_caster_r_wheel_joint");
                                jointstate.name.push_back("fl_caster_rotation_joint");
                                jointstate.name.push_back("bl_caster_r_wheel_joint");
                                jointstate.name.push_back("bl_caster_rotation_joint");
                                jointstate.name.push_back("br_caster_r_wheel_joint");
                                jointstate.name.push_back("br_caster_rotation_joint");
                                jointstate.name.push_back("fr_caster_r_wheel_joint");
                                jointstate.name.push_back("fr_caster_rotation_joint");
                                
                        }

                        controller_state.joint_names = jointstate.name;
                        controller_state.actual.positions = jointstate.position;
                        controller_state.actual.velocities = jointstate.velocity;

                        // publish jointstate message
                        topicPub_JointState.publish(jointstate);
                        topicPub_ControllerState.publish(controller_state);
                        
                        ROS_DEBUG("published new drive-chain configuration (JointState message)");
                        

                        if(m_bisInitialized)
                        {
                                // read Can only after initialization
#ifdef __SIM__
                                bIsError = false;
#else
                                bIsError = m_CanCtrlPltf->isPltfError();
#endif
                        }

                        // set data to diagnostics
                        if(bIsError)
                        {
                                diagnostics.level = 2;
                                diagnostics.name = "drive-chain can node";
                                diagnostics.message = "one or more drives are in Error mode";
                        }
                        else
                        {
                                if (m_bisInitialized)
                                {
                                        diagnostics.level = 0;
                                        diagnostics.name = "drive-chain can node";
                                        diagnostics.message = "drives operating normal";
                                }
                                else
                                {
                                        diagnostics.level = 1;
                                        diagnostics.name = "drive-chain can node";
                                        diagnostics.message = "drives are initializing";
                                }
                        }

                        // publish diagnostic message
                        topicPub_Diagnostic.publish(diagnostics);
                        ROS_DEBUG("published new drive-chain configuration (JointState message)");
                        //publish global diagnostic messages
                        diagnostic_msgs::DiagnosticArray diagnostics_gl;
                    diagnostics_gl.status.resize(1);
                    // set data to diagnostics
                    if(bIsError)
                    {
                      diagnostics_gl.status[0].level = 2;
                      diagnostics_gl.status[0].name = n.getNamespace();;
                      //TODOdiagnostics.status[0].message = error_msg_;
                    }
                    else
                    {
                      if (m_bisInitialized)
                      {
                        diagnostics_gl.status[0].level = 0;
                        diagnostics_gl.status[0].name = n.getNamespace(); //"schunk_powercube_chain";
                        diagnostics_gl.status[0].message = "base_drive_chain initialized and running";
                      }
                      else
                      {
                        diagnostics_gl.status[0].level = 1;
                        diagnostics_gl.status[0].name = n.getNamespace(); //"schunk_powercube_chain";
                        diagnostics_gl.status[0].message = "base_drive_chain not initialized";
                      }
                    }
                    // publish diagnostic message
                    topicPub_DiagnosticGlobal_.publish(diagnostics_gl);

                        return true;
                }
                
                // other function declarations
                bool initDrives();

#ifdef __SIM__
                void gazebo_joint_states_Callback(const sensor_msgs::JointState::ConstPtr& msg) {
                        for (unsigned int i=0; i<msg->name.size(); i++) {
                                //Drives
                                if(msg->name[i] == "fl_caster_r_wheel_joint") {
                                        m_gazeboPos[0] = msg->position[i];
                                        m_gazeboVel[0] = msg->velocity[i];
                                        m_gazeboStamp = msg->header.stamp;
                                }
                                else if(msg->name[i] == "bl_caster_r_wheel_joint") {
                                        m_gazeboPos[2] = msg->position[i];
                                        m_gazeboVel[2] = msg->velocity[i];
                                }
                                else if(msg->name[i] == "br_caster_r_wheel_joint") {
                                        m_gazeboPos[4] = msg->position[i];
                                        m_gazeboVel[4] = msg->velocity[i];
                                }
                                else if(msg->name[i] == "fr_caster_r_wheel_joint") {
                                        m_gazeboPos[6] = msg->position[i];
                                        m_gazeboVel[6] = msg->velocity[i];
                                }
                                
                                //Steers
                                else if(msg->name[i] == "fl_caster_rotation_joint") {
                                        m_gazeboPos[1] = msg->position[i];
                                        m_gazeboVel[1] = msg->velocity[i];
                                }
                                else if(msg->name[i] == "bl_caster_rotation_joint") {
                                        m_gazeboPos[3] = msg->position[i];
                                        m_gazeboVel[3] = msg->velocity[i];
                                }
                                else if(msg->name[i] == "br_caster_rotation_joint") {
                                        m_gazeboPos[5] = msg->position[i];
                                        m_gazeboVel[5] = msg->velocity[i];
                                }
                                else if(msg->name[i] == "fr_caster_rotation_joint") {
                                        m_gazeboPos[7] = msg->position[i];
                                        m_gazeboVel[7] = msg->velocity[i];
                                }
                        }
                }
#else

#endif
};

//#######################
//#### main programm ####
int main(int argc, char** argv)
{
        // initialize ROS, spezify name of node
        ros::init(argc, argv, "base_drive_chain");

        NodeClass nodeClass;

        // specify looprate of control-cycle
        ros::Rate loop_rate(100); // Hz 

        while(nodeClass.n.ok())
        {
#ifdef __SIM__

#else
                //Read-out of CAN buffer is only necessary during read-out of Elmo Recorder             
                if( nodeClass.m_bReadoutElmo ) 
                {
                        if(nodeClass.m_bisInitialized) nodeClass.m_CanCtrlPltf->evalCanBuffer();
                        if(nodeClass.m_CanCtrlPltf->ElmoRecordings(100, 0, "") == 0)
                        {
                                nodeClass.m_bReadoutElmo = false;
                                ROS_INFO("CPU consuming evalCanBuffer used for ElmoReadout deactivated");
                        }
                }
#endif

                nodeClass.publish_JointStates();
                
                loop_rate.sleep();
                ros::spinOnce();
        }

        return 0;
}

//##################################
//#### function implementations ####
bool NodeClass::initDrives()
{
        ROS_INFO("Initializing Base Drive Chain");

        // init member vectors
        m_Param.vdWheelNtrlPosRad.assign((m_iNumDrives),0);
//      m_Param.vdWheelNtrlPosRad.assign(4,0);
        // ToDo: replace the following steps by ROS configuration files
        // create Inifile class and set target inifile (from which data shall be read)
        IniFile iniFile;

        //n.param<std::string>("PltfIniLoc", sIniFileName, "Platform/IniFiles/Platform.ini");
        iniFile.SetFileName(sIniDirectory + "Platform.ini", "PltfHardwareCoB3.h");

        // get max Joint-Velocities (in rad/s) for Steer- and Drive-Joint
        iniFile.GetKeyDouble("DrivePrms", "MaxDriveRate", &m_Param.dMaxDriveRateRadpS, true);
        iniFile.GetKeyDouble("DrivePrms", "MaxSteerRate", &m_Param.dMaxSteerRateRadpS, true);

#ifdef __SIM__
        // get Offset from Zero-Position of Steering
        if(m_iNumDrives >=1)
                m_Param.vdWheelNtrlPosRad[0] = 0.0f;
        if(m_iNumDrives >=2)
                m_Param.vdWheelNtrlPosRad[1] = 0.0f;
        if(m_iNumDrives >=3)
                m_Param.vdWheelNtrlPosRad[2] = 0.0f;
        if(m_iNumDrives >=4)
                m_Param.vdWheelNtrlPosRad[3] = 0.0f;
#else
        // get Offset from Zero-Position of Steering
        if(m_iNumDrives >=1)
                iniFile.GetKeyDouble("DrivePrms", "Wheel1NeutralPosition", &m_Param.vdWheelNtrlPosRad[0], true);
        if(m_iNumDrives >=2)
                iniFile.GetKeyDouble("DrivePrms", "Wheel2NeutralPosition", &m_Param.vdWheelNtrlPosRad[1], true);
        if(m_iNumDrives >=3)
                iniFile.GetKeyDouble("DrivePrms", "Wheel3NeutralPosition", &m_Param.vdWheelNtrlPosRad[2], true);
        if(m_iNumDrives >=4)
                iniFile.GetKeyDouble("DrivePrms", "Wheel4NeutralPosition", &m_Param.vdWheelNtrlPosRad[3], true);

        //Convert Degree-Value from ini-File into Radian:
        for(int i=0; i<m_iNumDrives; i++)
        {
                m_Param.vdWheelNtrlPosRad[i] = MathSup::convDegToRad(m_Param.vdWheelNtrlPosRad[i]);
        }
#endif

        // debug log
        ROS_INFO("Initializing CanCtrlItf");
        bool bTemp1;
#ifdef __SIM__
        bTemp1 = true;
#else
        bTemp1 =  m_CanCtrlPltf->initPltf();
#endif
        // debug log
        ROS_INFO("Initializing done");


        return bTemp1;
}