sdh_only.cpp

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

// standard includes
#include <unistd.h>

// ROS includes
#include <ros/ros.h>
#include <urdf/model.h>
#include <actionlib/server/simple_action_server.h>

// ROS message includes
#include <std_msgs/Float32MultiArray.h>
#include <trajectory_msgs/JointTrajectory.h>
#include <sensor_msgs/JointState.h>
#include <control_msgs/FollowJointTrajectoryAction.h>
#include <control_msgs/JointTrajectoryControllerState.h>
#include <brics_actuator/JointVelocities.h>
#include <brics_actuator/JointValue.h>

// ROS service includes
#include <cob_srvs/Trigger.h>
#include <cob_srvs/SetOperationMode.h>

// ROS diagnostic msgs
#include <diagnostic_msgs/DiagnosticArray.h>

// external includes
#include <schunk_sdh/sdh.h>

class SdhNode
{
        public:
                ros::NodeHandle nh_;
        private:
                // declaration of topics to publish
                ros::Publisher topicPub_JointState_;
                ros::Publisher topicPub_ControllerState_;
                ros::Publisher topicPub_Diagnostics_;
                
                // topic subscribers
                ros::Subscriber subSetVelocitiesRaw_;
                ros::Subscriber subSetVelocities_;

                // service servers
                ros::ServiceServer srvServer_Init_;
                ros::ServiceServer srvServer_Stop_;
                ros::ServiceServer srvServer_Recover_;
                ros::ServiceServer srvServer_SetOperationMode_;

                // actionlib server
                actionlib::SimpleActionServer<control_msgs::FollowJointTrajectoryAction> as_;
                std::string action_name_;

                // service clients
                //--

                // other variables
                SDH::cSDH *sdh_;
                std::vector<SDH::cSDH::eAxisState> state_;

                std::string sdhdevicetype_;
                std::string sdhdevicestring_;
                int sdhdevicenum_;
                int baudrate_, id_read_, id_write_;
                double timeout_;

                bool isInitialized_;
                bool isError_;
                int DOF_;
                double pi_;
                
                trajectory_msgs::JointTrajectory traj_;
                
                std::vector<std::string> joint_names_;
                std::vector<int> axes_;
                std::vector<double> targetAngles_; // in degrees
                std::vector<double> velocities_; // in rad/s
                bool hasNewGoal_;
                std::string operationMode_; 
                
        public:
                SdhNode(std::string name):
                        as_(nh_, name, boost::bind(&SdhNode::executeCB, this, _1),true),
                        action_name_(name)
                {
                        pi_ = 3.1415926;
                        
                        nh_ = ros::NodeHandle ("~");
                        isError_ = false;
                        // diagnostics
                        topicPub_Diagnostics_ = nh_.advertise<diagnostic_msgs::DiagnosticArray>("/diagnostics", 1);

                }

                ~SdhNode() 
                {
                        if(isInitialized_)
                                sdh_->Close();
                        delete sdh_;
                }


                bool init()
                {
                        // initialize member variables
                        isInitialized_ = false;
                        hasNewGoal_ = false;

                        // implementation of topics to publish
                        topicPub_JointState_ = nh_.advertise<sensor_msgs::JointState>("/joint_states", 1);
                        topicPub_ControllerState_ = nh_.advertise<control_msgs::JointTrajectoryControllerState>("state", 1);

                        // pointer to sdh
                        sdh_ = new SDH::cSDH(false, false, 0); //(_use_radians=false, bool _use_fahrenheit=false, int _debug_level=0)

                        // implementation of service servers
                        srvServer_Init_ = nh_.advertiseService("init", &SdhNode::srvCallback_Init, this);
                        srvServer_Stop_ = nh_.advertiseService("stop", &SdhNode::srvCallback_Stop, this);
                        srvServer_Recover_ = nh_.advertiseService("recover", &SdhNode::srvCallback_Init, this); //HACK: There is no recover implemented yet, so we execute a init
                        srvServer_SetOperationMode_ = nh_.advertiseService("set_operation_mode", &SdhNode::srvCallback_SetOperationMode, this);
                        
                        subSetVelocitiesRaw_ = nh_.subscribe("set_velocities_raw", 1, &SdhNode::topicCallback_setVelocitiesRaw, this);
                        subSetVelocities_ = nh_.subscribe("set_velocities", 1, &SdhNode::topicCallback_setVelocities, this);

                        // getting hardware parameters from parameter server
                        nh_.param("sdhdevicetype", sdhdevicetype_, std::string("PCAN"));
                        nh_.param("sdhdevicestring", sdhdevicestring_, std::string("/dev/pcan0"));
                        nh_.param("sdhdevicenum", sdhdevicenum_, 0);
                        
                        nh_.param("baudrate", baudrate_, 1000000);
                        nh_.param("timeout", timeout_, (double)0.04);
                        nh_.param("id_read", id_read_, 43);
                        nh_.param("id_write", id_write_, 42);

                        // get joint_names from parameter server
                        ROS_INFO("getting joint_names from parameter server");
                        XmlRpc::XmlRpcValue joint_names_param;
                        if (nh_.hasParam("joint_names"))
                        {
                                nh_.getParam("joint_names", joint_names_param);
                        }
                        else
                        {
                                ROS_ERROR("Parameter joint_names not set, shutting down node...");
                                nh_.shutdown();
                                return false;
                        }
                        DOF_ = joint_names_param.size();
                        joint_names_.resize(DOF_);
                        for (int i = 0; i<DOF_; i++ )
                        {
                                joint_names_[i] = (std::string)joint_names_param[i];
                        }
                        std::cout << "joint_names = " << joint_names_param << std::endl;
                        
                        // define axes to send to sdh
                        axes_.resize(DOF_);
                        velocities_.resize(DOF_);
                        for(int i=0; i<DOF_; i++)
                        {
                                axes_[i] = i;
                        }
                        ROS_INFO("DOF = %d",DOF_);
                        
                        state_.resize(axes_.size());

                        nh_.param("OperationMode", operationMode_, std::string("position"));
                        return true;
                }

                void executeCB(const control_msgs::FollowJointTrajectoryGoalConstPtr &goal)
                {                       
                        ROS_INFO("sdh: executeCB");
                        if (operationMode_ != "position")
                        {
                                ROS_ERROR("%s: Rejected, sdh not in position mode", action_name_.c_str());
                                as_.setAborted();
                                return;
                        }
                        if (!isInitialized_)
                        {
                                ROS_ERROR("%s: Rejected, sdh not initialized", action_name_.c_str());
                                as_.setAborted();
                                return;
                        }

                        if (goal->trajectory.points.empty() || goal->trajectory.points[0].positions.size() != size_t(DOF_))
                        {
                                ROS_ERROR("%s: Rejected, malformed FollowJointTrajectoryGoal", action_name_.c_str());
                                as_.setAborted();
                                return;
                        }
                        while (hasNewGoal_ == true ) usleep(10000);

                        std::map<std::string,int> dict;
                        for (int idx=0; idx<goal->trajectory.joint_names.size(); idx++)
                        {
                                dict[goal->trajectory.joint_names[idx]] = idx;
                        }

                        targetAngles_.resize(DOF_);
                        targetAngles_[0] = goal->trajectory.points[0].positions[dict["sdh_knuckle_joint"]]*180.0/pi_; // sdh_knuckle_joint
                        targetAngles_[1] = goal->trajectory.points[0].positions[dict["sdh_finger_22_joint"]]*180.0/pi_; // sdh_finger22_joint
                        targetAngles_[2] = goal->trajectory.points[0].positions[dict["sdh_finger_23_joint"]]*180.0/pi_; // sdh_finger23_joint
                        targetAngles_[3] = goal->trajectory.points[0].positions[dict["sdh_thumb_2_joint"]]*180.0/pi_; // sdh_thumb2_joint
                        targetAngles_[4] = goal->trajectory.points[0].positions[dict["sdh_thumb_3_joint"]]*180.0/pi_; // sdh_thumb3_joint
                        targetAngles_[5] = goal->trajectory.points[0].positions[dict["sdh_finger_12_joint"]]*180.0/pi_; // sdh_finger12_joint
                        targetAngles_[6] = goal->trajectory.points[0].positions[dict["sdh_finger_13_joint"]]*180.0/pi_; // sdh_finger13_joint
                        ROS_INFO("received position goal: [['sdh_knuckle_joint', 'sdh_thumb_2_joint', 'sdh_thumb_3_joint', 'sdh_finger_12_joint', 'sdh_finger_13_joint', 'sdh_finger_22_joint', 'sdh_finger_23_joint']] = [%f,%f,%f,%f,%f,%f,%f]",goal->trajectory.points[0].positions[dict["sdh_knuckle_joint"]],goal->trajectory.points[0].positions[dict["sdh_thumb_2_joint"]],goal->trajectory.points[0].positions[dict["sdh_thumb_3_joint"]],goal->trajectory.points[0].positions[dict["sdh_finger_12_joint"]],goal->trajectory.points[0].positions[dict["sdh_finger_13_joint"]],goal->trajectory.points[0].positions[dict["sdh_finger_22_joint"]],goal->trajectory.points[0].positions[dict["sdh_finger_23_joint"]]);
                
                        hasNewGoal_ = true;
                        
                        usleep(500000); // needed sleep until sdh starts to change status from idle to moving
                        
                        bool finished = false;
                        while(finished == false)
                        {
                                if (as_.isNewGoalAvailable())
                                {
                                        ROS_WARN("%s: Aborted", action_name_.c_str());
                                        as_.setAborted();
                                        return;
                                }
                                for ( unsigned int i = 0; i < state_.size(); i++ )
                                {
                                        ROS_DEBUG("state[%d] = %d",i,state_[i]);
                                        if (state_[i] == 0)
                                        {
                                                finished = true;
                                        }
                                        else
                                        {       
                                                finished = false;
                                        }
                                }
                                usleep(10000);
                                //feedback_ = 
                                //as_.send feedback_
                        }

                        // set the action state to succeeded                    
                        ROS_INFO("%s: Succeeded", action_name_.c_str());
                        //result_.result.data = "succesfully received new goal";
                        //result_.success = 1;
                        //as_.setSucceeded(result_);
                        as_.setSucceeded();
                }

                void topicCallback_setVelocitiesRaw(const std_msgs::Float32MultiArrayPtr& velocities)
                {
                        if (!isInitialized_)
                        {
                                ROS_ERROR("%s: Rejected, sdh not initialized", action_name_.c_str());
                                return;
                        }
                        if(velocities->data.size() != velocities_.size()){
                                ROS_ERROR("Velocity array dimension mismatch");
                                return;
                        }
                        if (operationMode_ != "velocity")
                        {
                                ROS_ERROR("%s: Rejected, sdh not in velocity mode", action_name_.c_str());
                                return;
                        }

                        // TODO: write proper lock!
                        while (hasNewGoal_ == true ) usleep(10000);

                        velocities_[0] = velocities->data[0] * 180.0 / pi_; // sdh_knuckle_joint
                        velocities_[1] = velocities->data[5] * 180.0 / pi_; // sdh_finger22_joint
                        velocities_[2] = velocities->data[6] * 180.0 / pi_; // sdh_finger23_joint
                        velocities_[3] = velocities->data[1] * 180.0 / pi_; // sdh_thumb2_joint
                        velocities_[4] = velocities->data[2] * 180.0 / pi_; // sdh_thumb3_joint
                        velocities_[5] = velocities->data[3] * 180.0 / pi_; // sdh_finger12_joint
                        velocities_[6] = velocities->data[4] * 180.0 / pi_; // sdh_finger13_joint

                        hasNewGoal_ = true;
                }
                bool parseDegFromJointValue(const brics_actuator::JointValue& val, double &deg_val){
                    if (val.unit == "rad/s"){
                        deg_val = val.value  * 180.0 / pi_;
                        return true;
                    }else if (val.unit == "deg/s"){
                        deg_val = val.value;
                        return true;
                    }else {
                        ROS_ERROR_STREAM("Rejected message, unit '" << val.unit << "' not supported");
                        return false;
                    }
                }
                void topicCallback_setVelocities(const brics_actuator::JointVelocities::ConstPtr& msg)
                {
                        if (!isInitialized_)
                        {
                                ROS_ERROR("%s: Rejected, sdh not initialized", action_name_.c_str());
                                return;
                        }
                        if(msg->velocities.size() != velocities_.size()){
                                ROS_ERROR("Velocity array dimension mismatch");
                                return;
                        }
                        if (operationMode_ != "velocity")
                        {
                                ROS_ERROR("%s: Rejected, sdh not in velocity mode", action_name_.c_str());
                                return;
                        }

                        // TODO: write proper lock!
                        while (hasNewGoal_ == true ) usleep(10000);
                        bool valid = true;

                        valid = valid && parseDegFromJointValue(msg->velocities[0], velocities_[0]); // sdh_knuckle_joint
                        valid = valid && parseDegFromJointValue(msg->velocities[5], velocities_[1]); // sdh_finger22_joint
                        valid = valid && parseDegFromJointValue(msg->velocities[6], velocities_[2]); // sdh_finger23_joint
                        valid = valid && parseDegFromJointValue(msg->velocities[1], velocities_[3]); // sdh_thumb2_joint
                        valid = valid && parseDegFromJointValue(msg->velocities[2], velocities_[4]); // sdh_thumb3_joint
                        valid = valid && parseDegFromJointValue(msg->velocities[3], velocities_[5]); // sdh_finger12_joint
                        valid = valid && parseDegFromJointValue(msg->velocities[4], velocities_[6]); // sdh_finger13_joint

                        if (valid) hasNewGoal_ = true;
                }               
                bool srvCallback_Init(cob_srvs::Trigger::Request &req,
                                                        cob_srvs::Trigger::Response &res )
                {

                        if (isInitialized_ == false)
                        {
                                //Init Hand connection  
                                
                                try
                                {
                                        if(sdhdevicetype_.compare("RS232")==0)
                                        {
                                                sdh_->OpenRS232( sdhdevicenum_, 115200, 1, sdhdevicestring_.c_str());
                                                ROS_INFO("Initialized RS232 for SDH");
                                                isInitialized_ = true;
                                        }
                                        if(sdhdevicetype_.compare("PCAN")==0)
                                        {
                                                ROS_INFO("Starting initializing PEAKCAN");
                                                sdh_->OpenCAN_PEAK(baudrate_, timeout_, id_read_, id_write_, sdhdevicestring_.c_str());
                                                ROS_INFO("Initialized PEAK CAN for SDH");
                                                isInitialized_ = true;
                                        }
                                        if(sdhdevicetype_.compare("ESD")==0)
                                        {
                                                ROS_INFO("Starting initializing ESD");
                                                if(strcmp(sdhdevicestring_.c_str(), "/dev/can0") == 0)
                                                {
                                                        ROS_INFO("Initializing ESD on device %s",sdhdevicestring_.c_str());
                                                        sdh_->OpenCAN_ESD(0, baudrate_, timeout_, id_read_, id_write_ );
                                                }
                                                else if(strcmp(sdhdevicestring_.c_str(), "/dev/can1") == 0)
                                                {
                                                        ROS_INFO("Initializin ESD on device %s",sdhdevicestring_.c_str());
                                                        sdh_->OpenCAN_ESD(1, baudrate_, timeout_, id_read_, id_write_ );
                                                }
                                                else
                                                {
                                                        ROS_ERROR("Currently only support for /dev/can0 and /dev/can1");
                                                        res.success.data = false;
                                                        res.error_message.data = "Currently only support for /dev/can0 and /dev/can1";
                                                        return true;
                                                }
                                                ROS_INFO("Initialized ESDCAN for SDH"); 
                                                isInitialized_ = true;
                                        }
                                }
                                catch (SDH::cSDHLibraryException* e)
                                {
                                        ROS_ERROR("An exception was caught: %s", e->what());
                                        res.success.data = false;
                                        res.error_message.data = e->what();
                                        delete e;
                                        return true;
                                }
                        }
                        else
                        {
                                ROS_WARN("...sdh already initialized...");
                                res.success.data = true;
                                res.error_message.data = "sdh already initialized";
                        }
                        
                        res.success.data = true;
                        return true;
                }

                bool srvCallback_Stop(cob_srvs::Trigger::Request &req,
                                                        cob_srvs::Trigger::Response &res )
                {
                        ROS_INFO("Stopping sdh");

                        // stopping all arm movements
                        try
                        {
                                sdh_->Stop();
                        }
                        catch (SDH::cSDHLibraryException* e)
                        {
                                ROS_ERROR("An exception was caught: %s", e->what());
                                delete e;
                        }

                ROS_INFO("Stopping sdh succesfull");
                res.success.data = true;
                return true;
        }

        bool srvCallback_Recover(cob_srvs::Trigger::Request &req,
                                                        cob_srvs::Trigger::Response &res )
        {
                ROS_WARN("Service recover not implemented yet");
                res.success.data = true;
                res.error_message.data = "Service recover not implemented yet";
                return true;
        }
        
        bool srvCallback_SetOperationMode(cob_srvs::SetOperationMode::Request &req,
                                                                        cob_srvs::SetOperationMode::Response &res )
        {
                hasNewGoal_ = false;
                sdh_->Stop();
                ROS_INFO("Set operation mode to [%s]", req.operation_mode.data.c_str());
                operationMode_ = req.operation_mode.data;
                res.success.data = true;
                if( operationMode_ == "position"){
                        sdh_->SetController(SDH::cSDH::eCT_POSE);
                }else if( operationMode_ == "velocity"){
                        try{
                                sdh_->SetController(SDH::cSDH::eCT_VELOCITY);
                                sdh_->SetAxisEnable(sdh_->All, 1.0);
                        }
                        catch (SDH::cSDHLibraryException* e)
                        {
                                ROS_ERROR("An exception was caught: %s", e->what());
                                delete e;
                        }
                }else{
                        ROS_ERROR_STREAM("Operation mode '" << req.operation_mode.data << "'  not supported");
                }
                return true;
        }

        void updateSdh()
        {
                ROS_DEBUG("updateJointState");
                if (isInitialized_ == true)
                {
                        if (hasNewGoal_ == true)
                        {
                                // stop sdh first when new goal arrived
                                try
                                {
                                        sdh_->Stop();
                                }
                                catch (SDH::cSDHLibraryException* e)
                                {
                                        ROS_ERROR("An exception was caught: %s", e->what());
                                        delete e;
                                }
                
                                if (operationMode_ == "position")
                                {
                                        ROS_DEBUG("moving sdh in position mode");

                                        try
                                        {
                                                sdh_->SetAxisTargetAngle( axes_, targetAngles_ );
                                                sdh_->MoveHand(false);
                                        }
                                        catch (SDH::cSDHLibraryException* e)
                                        {
                                                ROS_ERROR("An exception was caught: %s", e->what());
                                                delete e;
                                        }
                                }
                                else if (operationMode_ == "velocity")
                                {
                                        ROS_DEBUG("moving sdh in velocity mode");
                                        try
                                        {
                                                sdh_->SetAxisTargetVelocity(axes_,velocities_);
                                                // ROS_DEBUG_STREAM("velocities: " << velocities_[0] << " "<< velocities_[1] << " "<< velocities_[2] << " "<< velocities_[3] << " "<< velocities_[4] << " "<< velocities_[5] << " "<< velocities_[6]);
                                        }
                                        catch (SDH::cSDHLibraryException* e)
                                        {
                                                ROS_ERROR("An exception was caught: %s", e->what());
                                                delete e;
                                        }
                                }
                                else if (operationMode_ == "effort")
                                {
                                        ROS_DEBUG("moving sdh in effort mode");
                                        //sdh_->MoveVel(goal->trajectory.points[0].velocities);
                                        ROS_WARN("Moving in effort mode currently disabled");
                                }
                                else
                                {
                                        ROS_ERROR("sdh neither in position nor in velocity nor in effort mode. OperationMode = [%s]", operationMode_.c_str());
                                }
                                
                                hasNewGoal_ = false;
                        }

                        // read and publish joint angles and velocities
                        std::vector<double> actualAngles;
                        try
                        {
                                actualAngles = sdh_->GetAxisActualAngle( axes_ );
                        }
                        catch (SDH::cSDHLibraryException* e)
                        {
                                ROS_ERROR("An exception was caught: %s", e->what());
                                delete e;
                        }
                        std::vector<double> actualVelocities;
                        try
                        {
                                actualVelocities = sdh_->GetAxisActualVelocity( axes_ );
                        }
                        catch (SDH::cSDHLibraryException* e)
                        {
                                ROS_ERROR("An exception was caught: %s", e->what());
                                delete e;
                        }
                        
                        ROS_DEBUG("received %d angles from sdh",(int)actualAngles.size());
                        
                        ros::Time time = ros::Time::now();
                        
                        // create joint_state message
                        sensor_msgs::JointState msg;
                        msg.header.stamp = time;
                        msg.name.resize(DOF_);
                        msg.position.resize(DOF_);
                        msg.velocity.resize(DOF_);
                        msg.effort.resize(DOF_);
                        // set joint names and map them to angles
                        msg.name = joint_names_;
                        //['sdh_knuckle_joint', 'sdh_thumb_2_joint', 'sdh_thumb_3_joint', 'sdh_finger_12_joint', 'sdh_finger_13_joint', 'sdh_finger_22_joint', 'sdh_finger_23_joint']
                        // pos
                        msg.position[0] = actualAngles[0]*pi_/180.0; // sdh_knuckle_joint
                        msg.position[1] = actualAngles[3]*pi_/180.0; // sdh_thumb_2_joint
                        msg.position[2] = actualAngles[4]*pi_/180.0; // sdh_thumb_3_joint
                        msg.position[3] = actualAngles[5]*pi_/180.0; // sdh_finger_12_joint
                        msg.position[4] = actualAngles[6]*pi_/180.0; // sdh_finger_13_joint
                        msg.position[5] = actualAngles[1]*pi_/180.0; // sdh_finger_22_joint
                        msg.position[6] = actualAngles[2]*pi_/180.0; // sdh_finger_23_joint
                        // vel                  
                        msg.velocity[0] = actualVelocities[0]*pi_/180.0; // sdh_knuckle_joint
                        msg.velocity[1] = actualVelocities[3]*pi_/180.0; // sdh_thumb_2_joint
                        msg.velocity[2] = actualVelocities[4]*pi_/180.0; // sdh_thumb_3_joint
                        msg.velocity[3] = actualVelocities[5]*pi_/180.0; // sdh_finger_12_joint
                        msg.velocity[4] = actualVelocities[6]*pi_/180.0; // sdh_finger_13_joint
                        msg.velocity[5] = actualVelocities[1]*pi_/180.0; // sdh_finger_22_joint
                        msg.velocity[6] = actualVelocities[2]*pi_/180.0; // sdh_finger_23_joint
                        // publish message
                        topicPub_JointState_.publish(msg);
                        
                        
                        // because the robot_state_publisher doen't know about the mimic joint, we have to publish the coupled joint separately
                        sensor_msgs::JointState  mimicjointmsg;
                        mimicjointmsg.header.stamp = time;
                        mimicjointmsg.name.resize(1);
                        mimicjointmsg.position.resize(1);
                        mimicjointmsg.velocity.resize(1);
                        mimicjointmsg.name[0] = "sdh_finger_21_joint";
                        mimicjointmsg.position[0] = msg.position[0]; // sdh_knuckle_joint = sdh_finger_21_joint
                        mimicjointmsg.velocity[0] = msg.velocity[0]; // sdh_knuckle_joint = sdh_finger_21_joint
                        topicPub_JointState_.publish(mimicjointmsg);
                        
                        
                        // publish controller state message
                        control_msgs::JointTrajectoryControllerState controllermsg;
                        controllermsg.header.stamp = time;
                        controllermsg.joint_names.resize(DOF_);
                        controllermsg.desired.positions.resize(DOF_);
                        controllermsg.desired.velocities.resize(DOF_);
                        controllermsg.actual.positions.resize(DOF_);
                        controllermsg.actual.velocities.resize(DOF_);
                        controllermsg.error.positions.resize(DOF_);
                        controllermsg.error.velocities.resize(DOF_);
                        // set joint names and map them to angles
                        controllermsg.joint_names = joint_names_;
                        //['sdh_knuckle_joint', 'sdh_thumb_2_joint', 'sdh_thumb_3_joint', 'sdh_finger_12_joint', 'sdh_finger_13_joint', 'sdh_finger_22_joint', 'sdh_finger_23_joint']
                        // desired pos
                        if (targetAngles_.size() != 0)
                        {
                                controllermsg.desired.positions[0] = targetAngles_[0]*pi_/180.0; // sdh_knuckle_joint
                                controllermsg.desired.positions[1] = targetAngles_[3]*pi_/180.0; // sdh_thumb_2_joint
                                controllermsg.desired.positions[2] = targetAngles_[4]*pi_/180.0; // sdh_thumb_3_joint
                                controllermsg.desired.positions[3] = targetAngles_[5]*pi_/180.0; // sdh_finger_12_joint
                                controllermsg.desired.positions[4] = targetAngles_[6]*pi_/180.0; // sdh_finger_13_joint
                                controllermsg.desired.positions[5] = targetAngles_[1]*pi_/180.0; // sdh_finger_22_joint
                                controllermsg.desired.positions[6] = targetAngles_[2]*pi_/180.0; // sdh_finger_23_joint
                        }
                        // desired vel
                                // they are all zero
                        // actual pos                   
                        controllermsg.actual.positions = msg.position;
                        // actual vel
                        controllermsg.actual.velocities = msg.velocity;
                        // error, calculated out of desired and actual values
                        for (int i = 0; i<DOF_; i++ )
                        {
                                controllermsg.error.positions[i] = controllermsg.desired.positions[i] - controllermsg.actual.positions[i];
                                controllermsg.error.velocities[i] = controllermsg.desired.velocities[i] - controllermsg.actual.velocities[i];
                        }
                        // publish controller message
                        topicPub_ControllerState_.publish(controllermsg);

                        // read sdh status
                        state_ = sdh_->GetAxisActualState(axes_);
                }
                else
                {
                        ROS_DEBUG("sdh not initialized");
                }
                // publishing diagnotic messages
            diagnostic_msgs::DiagnosticArray diagnostics;
            diagnostics.status.resize(1);
            // set data to diagnostics
            if(isError_)
            {
              diagnostics.status[0].level = 2;
              diagnostics.status[0].name = "schunk_powercube_chain";
              diagnostics.status[0].message = "one or more drives are in Error mode";
            }
            else
            {
              if (isInitialized_)
              {
                diagnostics.status[0].level = 0;
                diagnostics.status[0].name = nh_.getNamespace(); //"schunk_powercube_chain";
                diagnostics.status[0].message = "sdh initialized and running";  
              }
              else
              {
                diagnostics.status[0].level = 1;
                diagnostics.status[0].name = nh_.getNamespace(); //"schunk_powercube_chain";
                diagnostics.status[0].message = "sdh not initialized";
              }
            }
            // publish diagnostic message
            topicPub_Diagnostics_.publish(diagnostics);

        }
}; //SdhNode

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

        //SdhNode sdh_node(ros::this_node::getName() + "/joint_trajectory_action");
        SdhNode sdh_node(ros::this_node::getName() + "/follow_joint_trajectory");
        if (!sdh_node.init()) return 0;
        
        ROS_INFO("...sdh node running...");

        double frequency;
        if (sdh_node.nh_.hasParam("frequency"))
        {
                sdh_node.nh_.getParam("frequency", frequency);
        }
        else
        {
                frequency = 5; //Hz
                ROS_WARN("Parameter frequency not available, setting to default value: %f Hz", frequency);
        }

        //sleep(1);
        ros::Rate loop_rate(frequency); // Hz
        while(sdh_node.nh_.ok())
        {
                // publish JointState
                sdh_node.updateSdh();
                
                // sleep and waiting for messages, callbacks
                ros::spinOnce();
                loop_rate.sleep();
        }

        return 0;
}