pg70_rs232_control_lib.cpp

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/*********************************************************************************************/
/* Author: Frantisek Durovsky */

#ifndef PG70_RS232_CONTROL_LIB_CPP
#define PG70_RS232_CONTROL_LIB_CPP

#include <pg70_rs232_control.h>

namespace schunk_pg70
{

PG70_serial::PG70_serial(ros::NodeHandle *nh) :
    act_position_(-1),
    pg70_error_(0xff)
{
  //Read launch file params
  nh->getParam("schunk_pg70/portname", port_name_);
  nh->getParam("schunk_pg70/baudrate", baudrate_);
  nh->getParam("schunk_pg70/gripper_id", gripper_id_);
  
  //Initialize and open serial port
  com_port_ = new serial::Serial (port_name_, (uint32_t)baudrate_, serial::Timeout::simpleTimeout(100));
  if (com_port_->isOpen())
  {
    ROS_INFO_STREAM("PG70: Serial port " << port_name_ << " openned");
      
    //Get initial state and discard input buffer
    while(pg70_error_ == 0xff)
    {
      pg70_error_ = getError(com_port_);
      ros::Duration(WAIT_FOR_RESPONSE_INTERVAL).sleep();
    }
    
    //Start periodic gripper state reading 
    getPeriodicPositionUpdate(com_port_, TF_UPDATE_PERIOD);
  }
  else
    ROS_ERROR_STREAM("PG70: Serial port " << port_name_ << " not opened");
}

PG70_serial::~PG70_serial()
{
  com_port_->close();      //Close port
  delete com_port_;        //delete object
}

void
PG70_serial::reference(serial::Serial *port)
{
  std::vector<uint8_t> output;
  output.push_back(0x05);           //message from master to module
  output.push_back(gripper_id_);    //module id
  output.push_back(0x01);           //Data Length
  output.push_back(0x92);           //Command reference

  //Checksum calculation
  uint16_t crc = 0;

  for(size_t i = 0; i < output.size(); i++)
    crc = CRC16(crc,output[i]);

  //Add checksum to the output buffer
  output.push_back(crc & 0x00ff);
  output.push_back((crc & 0xff00) >> 8);

  //Send message to the module
  port->write(output);
}

uint8_t
PG70_serial::getError(serial::Serial *port)
{
  ROS_INFO("Reading current module state...");
  std::vector<uint8_t> output;
  output.push_back(0x05);           //message from master to module
  output.push_back(gripper_id_);    //module id
  output.push_back(0x06);           //Data Length
  output.push_back(0x95);           //Command get state
  output.push_back(0x00);
  output.push_back(0x00);
  output.push_back(0x00);
  output.push_back(0x00);
  output.push_back(0x01);           //get state only once
 
  //Checksum calculation
  uint16_t crc = 0;

  for(size_t i = 0; i < output.size(); i++)
    crc = CRC16(crc,output[i]);

  //Add checksum to the output buffer
  output.push_back(crc & 0x00ff);
  output.push_back((crc & 0xff00) >> 8);

  //Send message to the module and wait for response
  port->write(output);
  ros::Duration(WAIT_FOR_RESPONSE_INTERVAL).sleep();

  //Read response
  std::vector<uint8_t> input;
  port->read(input, INPUT_BUFFER_SIZE);

  //Process current state message
  int get_state_index = 0;
  if(input.size() > 0)
  {
    if(input.size() > 7)
    {
      for(size_t i = 0; i < input.size(); i++)
        if ((input[i] == 0x07) && (input[i+1] == 0x95)) get_state_index = i;

      int pg70_error_ = input[get_state_index + 7];

      switch (pg70_error_)
      {
        case 0x00: ROS_INFO("PG70: No error detected"); break;
        case 0xC8: ROS_ERROR("PG70: Error: 0xC8 detected: Wrong ramp type"); break;
        case 0xD2: ROS_ERROR("PG70: Error: 0xD2 detected: Config memory"); break;
        case 0xD3: ROS_ERROR("PG70: Error: 0xD3 detected: Program memory"); break;
        case 0xD4: ROS_ERROR("PG70: Error: 0xD4 detected: Invalid phrase"); break;
        case 0xD5: ROS_ERROR("PG70: Error: 0xD5 detected: Soft low"); break;
        case 0xD6: ROS_ERROR("PG70: Error: 0xD6 detected: Soft high"); break;
        case 0xD7: ROS_ERROR("PG70: Error: 0xD7 detected: Pressure"); break;
        case 0xD8: ROS_ERROR("PG70: Error: 0xD8 detected: Service required"); break;
        case 0xD9: ROS_ERROR("PG70: Error: 0xD9 detected: Emergency stop"); break;
        case 0xDA: ROS_ERROR("PG70: Error: 0xDA detected: Tow"); break;
        case 0xE4: ROS_ERROR("PG70: Error: 0xE4 detected: Too fast"); break;
        case 0xEC: ROS_ERROR("PG70: Error: 0xEC detected: Math error"); break;
        case 0xDB: ROS_ERROR("PG70: Error: 0xDB detected: VPC3"); break;
        case 0xDC: ROS_ERROR("PG70: Error: 0xDC detected: Fragmentation"); break;
        case 0xDE: ROS_ERROR("PG70: Error: 0xDE detected: Current"); break;
        case 0xDF: ROS_ERROR("PG70: Error: 0xDF detected: I2T"); break;
        case 0xE0: ROS_ERROR("PG70: Error: 0xE0 detected: Initialize"); break;
        case 0xE1: ROS_ERROR("PG70: Error: 0xE1 detected: Internal"); break;
        case 0xE2: ROS_ERROR("PG70: Error: 0xE2 detected: Hard low"); break;
        case 0xE3: ROS_ERROR("PG70: Error: 0xE3 detected: Hard high"); break;
        case 0x70: ROS_ERROR("PG70: Error: 0x70 detected: Temp low"); break;
        case 0x71: ROS_ERROR("PG70: Error: 0x71 detected: Temp high"); break;
        case 0x72: ROS_ERROR("PG70: Error: 0x72 detected: Logic low"); break;
        case 0x73: ROS_ERROR("PG70: Error: 0x73 detected: Logic high"); break;
        case 0x74: ROS_ERROR("PG70: Error: 0x74 detected: Motor voltage low"); break;
        case 0x75: ROS_ERROR("PG70: Error: 0x75 detected: Motor voltage high"); break;
        case 0x76: ROS_ERROR("PG70: Error: 0x76 detected: Cable break"); break;
        case 0x78: ROS_ERROR("PG70: Error: 0x78 detected: Motor temp"); break;
      }
      //Re-start periodic position reading 
      getPeriodicPositionUpdate(com_port_, TF_UPDATE_PERIOD);
      return((uint8_t)pg70_error_);
    }
    else
    {
      //Re-start periodic position reading 
      getPeriodicPositionUpdate(com_port_, TF_UPDATE_PERIOD);
      return(0xff) ;
    }
  }  
}

void
PG70_serial::acknowledgeError(serial::Serial *port)
{
  std::vector<uint8_t> output;
  output.push_back(0x05);          //message from master to module
  output.push_back(gripper_id_);   //module id
  output.push_back(0x01);          //Data Length
  output.push_back(0x8b);          //Command CMD ACK

  //Checksum calculation
  uint16_t crc = 0;

  for(size_t i = 0; i < output.size(); i++)
    crc = CRC16(crc,output[i]);

  //Add checksum to the output buffer
  output.push_back(crc & 0x00ff);
  output.push_back((crc & 0xff00) >> 8);

  //Send message to the module
  port->write(output);
}

void
PG70_serial::setPosition(serial::Serial *port, int goal_position, int velocity, int acceleration)
{
  ROS_INFO_STREAM("PG70: Moving from: " << act_position_ << " [mm] to " << goal_position << " [mm]");
  
  std::vector<uint8_t> output;
  output.push_back(0x05);                //message from master to module
  output.push_back(gripper_id_);          //module id
  output.push_back(0x0D);                //D-Len
  output.push_back(0xb0);                //Command mov pos

  //Position <0-69>mm
  unsigned int IEEE754_bytes[4];
  float_to_IEEE_754(goal_position,IEEE754_bytes);

  output.push_back(IEEE754_bytes[0]);    //Position first byte
  output.push_back(IEEE754_bytes[1]);    //Position second byte
  output.push_back(IEEE754_bytes[2]);    //Position third byte
  output.push_back(IEEE754_bytes[3]);    //Position fourth byte

  //Velocity<0-82>mm/s
  float_to_IEEE_754(velocity, IEEE754_bytes);
  output.push_back(IEEE754_bytes[0]);    //Velocity first byte
  output.push_back(IEEE754_bytes[1]);    //Velocity second byte
  output.push_back(IEEE754_bytes[2]);    //Velocity third byte
  output.push_back(IEEE754_bytes[3]);    //Velocity fourth byte

  //Acceleration<0-320>mm/s2
  float_to_IEEE_754(acceleration, IEEE754_bytes);
  output.push_back(IEEE754_bytes[0]);    //Acceleration first byte
  output.push_back(IEEE754_bytes[1]);    //Acceleration second byte
  output.push_back(IEEE754_bytes[2]);    //Acceleration third byte
  output.push_back(IEEE754_bytes[3]);    //Acceleration fourth byte

  //Checksum calculation
  uint16_t crc = 0;

  for(size_t i = 0; i < output.size(); i++)
    crc = CRC16(crc,output[i]);

  //Add checksum to the output buffer
  output.push_back(crc & 0x00ff);
  output.push_back((crc & 0xff00) >> 8);

  //Send message to the module
  port->write(output);
}

float
PG70_serial::getPosition(serial::Serial *port)
{
  std::vector<uint8_t> output;
  output.push_back(0x05);                 //message from master to module
  output.push_back(gripper_id_);           //module id
  output.push_back(0x06);                 //Data Length
  output.push_back(0x95);                 //Command get state
  output.push_back(0x00);
  output.push_back(0x00);
  output.push_back(0x00);
  output.push_back(0x00);
  output.push_back(0x01);                 //get state only once

  //Checksum calculation
  uint16_t crc = 0;

  for(size_t i = 0; i < output.size(); i++)
    crc = CRC16(crc,output[i]);

  //Add checksum to the output buffer
  output.push_back(crc & 0x00ff);
  output.push_back((crc & 0xff00) >> 8);

  //Send message to the module
  port->write(output);
  ros::Duration(0.1).sleep();

  std::vector<uint8_t> input;
  port->read(input, INPUT_BUFFER_SIZE);

  //Detect reached position response
  float act_position;

  if(input.size() > 0)
  {
    for(size_t i = 0; i < input.size(); i++)
    {
      if((input[i] == 0x07) && (input[i+1] == 0x95))
      {
        uint8_t raw[4] = {input[i+5], input[i+4], input[i+3], input[i+2]};
        act_position = IEEE_754_to_float(raw);
        ROS_INFO_STREAM("PG70 INFO: Actual position: " << act_position << " [mm]");
        return(act_position);
      }
      else if  ((input[i] == 0x05) && (input[i+1] == 0x94))
      {
        uint8_t raw[4] = {input[i+5], input[i+4], input[i+3], input[i+2]};
        act_position = IEEE_754_to_float(raw);
        ROS_INFO_STREAM("PG70 INFO: Actual position: " << act_position << " [mm]");
        return(act_position);
      }
    }
  }
}

void
PG70_serial::getPeriodicPositionUpdate(serial::Serial *port, float update_period)
{
  std::vector<uint8_t> output;
  output.push_back(0x05);                 //message from master to the module
  output.push_back(gripper_id_);          //gripper id
  output.push_back(0x06);                 //Data Length
  output.push_back(0x95);                 //Command get state
    
  unsigned int IEEE754_bytes[4];
  float_to_IEEE_754(update_period, IEEE754_bytes);
  
  output.push_back(IEEE754_bytes[0]);    //period first byte
  output.push_back(IEEE754_bytes[1]);    //period second byte
  output.push_back(IEEE754_bytes[2]);    //period third byte
  output.push_back(IEEE754_bytes[3]);    //period fourth byte
  output.push_back(0x07);

  //Checksum calculation
  uint16_t crc = 0;                      

  for(size_t i = 0; i < output.size(); i++)
    crc = CRC16(crc,output[i]);

  //Add checksum to the output buffer
  output.push_back(crc & 0x00ff);
  output.push_back((crc & 0xff00) >> 8);
  
  //Send get_state message to the module 
  port->write(output);   
}

void
PG70_serial::stop(serial::Serial *port)
{
  std::vector<uint8_t> output;
  output.push_back(0x05);         //message from master to module
  output.push_back(gripper_id_);  //module id
  output.push_back(0x01);         //D-Len
  output.push_back(0x91);         //Command stop

  //Checksum calculation
  uint16_t crc = 0;

  for(size_t i = 0; i < output.size(); i++)
    crc = CRC16(crc,output[i]);

  //Add checksum to the output buffer
  output.push_back(crc & 0x00ff);
  output.push_back((crc & 0xff00) >> 8);

  //Send message to the module
  port->write(output);
}

//CALLBACKS

bool
PG70_serial::referenceCallback(schunk_pg70::reference::Request &req,
                               schunk_pg70::reference::Response &res)
{
  ROS_INFO("PG70: Reference Cmd recieved ");
  reference(com_port_);     
}

bool
PG70_serial::setPositionCallback(schunk_pg70::set_position::Request &req,
                                 schunk_pg70::set_position::Response &res)
{
  
  //Check if goal request respects position limits <0-69> mm
  if ((req.goal_position >= MIN_GRIPPER_POS_LIMIT) && (req.goal_position < MAX_GRIPPER_POS_LIMIT))
  {
    //Check if goal request respects velocity limits <0-83> mm/s
    if((req.goal_velocity > MIN_GRIPPER_VEL_LIMIT) && (req.goal_velocity < MAX_GRIPPER_VEL_LIMIT))
    {
      //Check if goal request respects acceleration limits <0-320> mm/s2  
      if((req.goal_acceleration > MIN_GRIPPER_ACC_LIMIT) && (req.goal_acceleration <= MAX_GRIPPER_ACC_LIMIT))
      {
        setPosition(com_port_,req.goal_position, req.goal_velocity, req.goal_acceleration);
        res.goal_accepted = true;
      }
      else
      {
        ROS_WARN("PG70: Goal acceleration rejected!");
        res.goal_accepted = false;
      }
    }
    else
    {
      ROS_WARN("PG70: Goal velocity rejected!");
      res.goal_accepted = false;
    }
  }
  else
  {
    ROS_WARN("PG70: Goal position rejected!");
    res.goal_accepted = false;
  }
}

bool
PG70_serial::getPositionCallback(schunk_pg70::get_position::Request &req,
                                 schunk_pg70::get_position::Response &res)
{
  ROS_INFO("PG70: Get position request recieved");
  res.actual_position = getPosition(com_port_);   
}

bool
PG70_serial::getErrorCallback(schunk_pg70::get_error::Request &req,
                              schunk_pg70::get_error::Response &res)
{
  ROS_INFO("PG70: Get state request recieved");
  res.error_code = getError(com_port_);
}

bool
PG70_serial::acknowledgeErrorCallback(schunk_pg70::acknowledge_error::Request &req,
                                      schunk_pg70::acknowledge_error::Response &res)
{
  ROS_INFO("PG70: Cmd Acknowledge error recieved");
  acknowledgeError(com_port_);
  ros::Duration(WAIT_FOR_RESPONSE_INTERVAL).sleep();
  if(getError(com_port_) == 0x00)
    res.acknowledge_response = true;
  else
    res.acknowledge_response = false;
}

bool
PG70_serial::stopCallback(schunk_pg70::stop::Request &req,
                          schunk_pg70::stop::Response &res)
{
  ROS_INFO("PG70: Cmd Stop recieved");
  stop(com_port_);
  ros::Duration(WAIT_FOR_RESPONSE_INTERVAL).sleep();
  res.stop_result = getPosition(com_port_);
}

void
PG70_serial::timerCallback(const ros::TimerEvent &event)
{
  std::vector<uint8_t> input;
  com_port_->read(input,INPUT_BUFFER_SIZE);
 
  //Detect position reached response
  for(size_t i = 0; i < input.size(); i++)
  {
    if((input[i] == 0x05) && (input[i+1] == 0x94))
    {
      uint8_t raw[4] = {input[i+5], input[i+4], input[i+3], input[i+2]};
      act_position_ = IEEE_754_to_float(raw);
    }
    
    if((input[i] == 0x0F) && (input[i+1] == 0x95))
    {
      uint8_t raw[4] = {input[i+5], input[i+4], input[i+3], input[i+2]};
      act_position_ = IEEE_754_to_float(raw);
    }
    
    if((input[i] == 0x07) && (input[i+1] == 0x95))
    {
      uint8_t raw[4] = {input[i+5], input[i+4], input[i+3], input[i+2]};
      act_position_ = IEEE_754_to_float(raw);
    }
  }
  
  ROS_DEBUG_STREAM("Actual position: " << act_position_);
  
  //Publish TF
  pg70_joint_state_.header.stamp = ros::Time::now();
  pg70_joint_state_.name.clear();
  pg70_joint_state_.position.clear();
    
  pg70_joint_state_.name.push_back("pg70_finger1_joint");
  pg70_joint_state_.position.push_back(act_position_/URDF_SCALE_FACTOR);
  
  pg70_joint_state_.name.push_back("pg70_finger2_joint");
  pg70_joint_state_.position.push_back(act_position_/URDF_SCALE_FACTOR);
   
  joint_pub.publish(pg70_joint_state_);         
  
}

//ADDITIONAL FUNCTIONS

float
PG70_serial::IEEE_754_to_float(uint8_t *raw)
{
  int sign = (raw[0] >> 7) ? -1 : 1;
  int8_t exponent = (raw[0] << 1) + (raw[1] >> 7) - 126;

  uint32_t fraction_bits = ((raw[1] & 0x7F) << 16) + (raw[2] << 8) + raw[3];

  float fraction = 0.5f;
  for (uint8_t ii = 0; ii < 24; ++ii)
    fraction += ldexpf((fraction_bits >> (23 - ii)) & 1, -(ii + 1));

  float significand = sign * fraction;

  return ldexpf(significand, exponent);
}

void
PG70_serial::float_to_IEEE_754(float position, unsigned int *output_array)
{
  unsigned char *p_byte = (unsigned char*)(&position);

  for(size_t i = 0; i < sizeof(float); i++)
    output_array[i] = (static_cast<unsigned int>(p_byte[i]));
}

uint16_t
PG70_serial::CRC16(uint16_t crc, uint16_t data)
{
  const uint16_t tbl[256] = {
  0x0000, 0xC0C1, 0xC181, 0x0140, 0xC301, 0x03C0, 0x0280, 0xC241,
  0xC601, 0x06C0, 0x0780, 0xC741, 0x0500, 0xC5C1, 0xC481, 0x0440,
  0xCC01, 0x0CC0, 0x0D80, 0xCD41, 0x0F00, 0xCFC1, 0xCE81, 0x0E40,
  0x0A00, 0xCAC1, 0xCB81, 0x0B40, 0xC901, 0x09C0, 0x0880, 0xC841,
  0xD801, 0x18C0, 0x1980, 0xD941, 0x1B00, 0xDBC1, 0xDA81, 0x1A40,
  0x1E00, 0xDEC1, 0xDF81, 0x1F40, 0xDD01, 0x1DC0, 0x1C80, 0xDC41,
  0x1400, 0xD4C1, 0xD581, 0x1540, 0xD701, 0x17C0, 0x1680, 0xD641,
  0xD201, 0x12C0, 0x1380, 0xD341, 0x1100, 0xD1C1, 0xD081, 0x1040,
  0xF001, 0x30C0, 0x3180, 0xF141, 0x3300, 0xF3C1, 0xF281, 0x3240,
  0x3600, 0xF6C1, 0xF781, 0x3740, 0xF501, 0x35C0, 0x3480, 0xF441,
  0x3C00, 0xFCC1, 0xFD81, 0x3D40, 0xFF01, 0x3FC0, 0x3E80, 0xFE41,
  0xFA01, 0x3AC0, 0x3B80, 0xFB41, 0x3900, 0xF9C1, 0xF881, 0x3840,
  0x2800, 0xE8C1, 0xE981, 0x2940, 0xEB01, 0x2BC0, 0x2A80, 0xEA41,
  0xEE01, 0x2EC0, 0x2F80, 0xEF41, 0x2D00, 0xEDC1, 0xEC81, 0x2C40,
  0xE401, 0x24C0, 0x2580, 0xE541, 0x2700, 0xE7C1, 0xE681, 0x2640,
  0x2200, 0xE2C1, 0xE381, 0x2340, 0xE101, 0x21C0, 0x2080, 0xE041,
  0xA001, 0x60C0, 0x6180, 0xA141, 0x6300, 0xA3C1, 0xA281, 0x6240,
  0x6600, 0xA6C1, 0xA781, 0x6740, 0xA501, 0x65C0, 0x6480, 0xA441,
  0x6C00, 0xACC1, 0xAD81, 0x6D40, 0xAF01, 0x6FC0, 0x6E80, 0xAE41,
  0xAA01, 0x6AC0, 0x6B80, 0xAB41, 0x6900, 0xA9C1, 0xA881, 0x6840,
  0x7800, 0xB8C1, 0xB981, 0x7940, 0xBB01, 0x7BC0, 0x7A80, 0xBA41,
  0xBE01, 0x7EC0, 0x7F80, 0xBF41, 0x7D00, 0xBDC1, 0xBC81, 0x7C40,
  0xB401, 0x74C0, 0x7580, 0xB541, 0x7700, 0xB7C1, 0xB681, 0x7640,
  0x7200, 0xB2C1, 0xB381, 0x7340, 0xB101, 0x71C0, 0x7080, 0xB041,
  0x5000, 0x90C1, 0x9181, 0x5140, 0x9301, 0x53C0, 0x5280, 0x9241,
  0x9601, 0x56C0, 0x5780, 0x9741, 0x5500, 0x95C1, 0x9481, 0x5440,
  0x9C01, 0x5CC0, 0x5D80, 0x9D41, 0x5F00, 0x9FC1, 0x9E81, 0x5E40,
  0x5A00, 0x9AC1, 0x9B81, 0x5B40, 0x9901, 0x59C0, 0x5880, 0x9841,
  0x8801, 0x48C0, 0x4980, 0x8941, 0x4B00, 0x8BC1, 0x8A81, 0x4A40,
  0x4E00, 0x8EC1, 0x8F81, 0x4F40, 0x8D01, 0x4DC0, 0x4C80, 0x8C41,
  0x4400, 0x84C1, 0x8581, 0x4540, 0x8701, 0x47C0, 0x4680, 0x8641,
  0x8201, 0x42C0, 0x4380, 0x8341, 0x4100, 0x81C1, 0x8081, 0x4040
  };

  return(((crc & 0xFF00) >> 8)  ^ tbl[(crc & 0x00FF) ^ (data & 0x00FF)]);
}
}  //schunk_pg70

#endif //PG70_RS232_CONTROL_LIB_CPP