Hello, I am writing to ask a few questions about communication using the C3 Bridge Interface.
As I understand, ‘Dmitry’ is the author of this program, so I would especially like to address this to him.
While this is not directly related to RoboDK, I am trying to use the C3 Bridge, a communication interface employed when working with KUKA through RoboDK, to send motion commands to a KUKA robot.
To achieve this, I referenced the C3 Bridge documentation and developed a Python client program for communication. The code is as follows:
My main question is that although I use the ‘move’ method in my code to send motion commands through this program, the robot does not execute the command.
I have successfully read and assigned KUKA system variables through this example, but the process of sending motion commands is not going smoothly.
Could you please review the code I wrote and let me know what might be causing the issue?
Additionally, I am curious about the example in the documentation where the ‘position string’ in the 'payload' for a PTP command is formatted as:
‘{POS: X 0, Y 0, Z 0, A 0, B 0, C 0}’.
However, I want to send a PTP command using joint values instead of coordinates, so I formatted it as:
‘{AXIS: A1 0, A2 -90, A3 90, A4 0, A5 0, A6 0}’.
Could you tell me if this is an appropriate method?
Lastly, when sending motion commands to the C3 Bridge using a client program, what mode should the robot controller be in?
For instance, when using RoboDK, the KRL program is executed in ‘AUT’ mode after connecting with RoboDK via the communication driver. I am unsure about the proper setup when using a client program like mine to send commands to the C3 Bridge.
I apologize for asking a question not directly related to RoboDK, but I would greatly appreciate any response. Thank you for your continuous support.
Best regards.
As I understand, ‘Dmitry’ is the author of this program, so I would especially like to address this to him.
While this is not directly related to RoboDK, I am trying to use the C3 Bridge, a communication interface employed when working with KUKA through RoboDK, to send motion commands to a KUKA robot.
To achieve this, I referenced the C3 Bridge documentation and developed a Python client program for communication. The code is as follows:
Code:
import sys
import struct
import random
import socket
import time
from rdk_config import Config_host
__version__ = '1.1.0'
ENCODING = 'UTF-8'
# Message Tpyes (flag)
# 0 - CommandReadVariableAscii
# 1 - CommandWriteVariableAscii
# 11 - CommandMotion
class kukaClient:
def __init__(self, ip, port):
self.ip = ip
self.port = port
self.msg_id = random.randint(1, 100)
self.sock = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
try:
self.sock.connect((self.ip, self.port))
except socket.error as e:
print(f"Socket error: {e}")
sys.exit(-1)
def test_connection(self):
try:
sock = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
ret = sock.connect_ex((self.ip, self.port))
sock.close()
return ret == 0
except socket.error as e:
print(f"Socket error: {e}")
return False
@property
def can_connect(self):
return self.test_connection()
def move(self, motion_type, position, debug=True):
if not isinstance(position, str):
raise TypeError('Position values must be STRING.')
print("Position (original): ", position)
self.position = position.encode('utf-16le') # Wide format (UTF-16LE)
self.motion_type = motion_type
print("Position (encoded): ", self.position.hex()) # Print encoded position in hex for debugging
return self._move_robot(debug)
def _move_robot(self, debug):
req = self._pack_move_req()
print("req ready!")
self._send_req(req)
print("send ok")
_value = self._read_rsp_move(debug)
if debug:
print(_value)
return _value
def _pack_move_req(self):
position_len = len(self.position) // 2
flag = 11 # Wide format version of CommandMotion
req_len = 3 + 2 + len(self.position)
return struct.pack(
'!HHBBH' + str(len(self.position)) + 's',
self.msg_id, # Tag ID
req_len, # Message Length
flag, # Message Type
self.motion_type, # Motion Type
position_len, # Length of Position String (in characters)
self.position # Positon String
)
def _send_req(self, req):
print("_send_req: ", req)
self.rsp = None
try:
self.sock.sendall(req)
print("sock.sendall(req)")
self.rsp = self.sock.recv(1024)
print("self.rsp: ", self.rsp)
except socket.timeout:
print("Socket timeout occurred. No response received.")
except socket.error as e:
print(f"Socket error: {e}")
def _read_rsp_move(self, debug=False):
if self.rsp is None:
return None
header_format = '!HHBH'
header_size = struct.calcsize(header_format)
body = self.rsp[header_size:-3] # Exclude the 3-byte end marker
is_ok = self.rsp[-3:]
if debug:
print('Response:', self.rsp)
if is_ok.endswith(b'\x01'):
self.msg_id = (self.msg_id + 1) % 65536
return body.decode('utf-16le')
def close(self):
self.sock.close()
if __name__ == "__main__":
ip = 'xxx.xx.x.xxx' # C3 Bridge Interface Server IP address
port = 7000
client = kukaClient(ip, port)
if client.can_connect:
print("Connecting Success.")
stop_message = client.read('$STOPMESS')
if stop_message:
print(f"Robot is Stop Status: {stop_message}")
else:
print("Robot is Not Stop Status.")
# motion command example (PTP)
position = '{AXIS: A1 0, A2 -90, A3 90, A4 0, A5 0, A6 0}'
#position = '{POS: X 0, Y 0, Z 0, A 0, B 0, C 0}'
client.move(1, position, debug=True)
else:
print("Server Connecting Fail.")
client.close()My main question is that although I use the ‘move’ method in my code to send motion commands through this program, the robot does not execute the command.
I have successfully read and assigned KUKA system variables through this example, but the process of sending motion commands is not going smoothly.
Could you please review the code I wrote and let me know what might be causing the issue?
Additionally, I am curious about the example in the documentation where the ‘position string’ in the 'payload' for a PTP command is formatted as:
‘{POS: X 0, Y 0, Z 0, A 0, B 0, C 0}’.
However, I want to send a PTP command using joint values instead of coordinates, so I formatted it as:
‘{AXIS: A1 0, A2 -90, A3 90, A4 0, A5 0, A6 0}’.
Could you tell me if this is an appropriate method?
Lastly, when sending motion commands to the C3 Bridge using a client program, what mode should the robot controller be in?
For instance, when using RoboDK, the KRL program is executed in ‘AUT’ mode after connecting with RoboDK via the communication driver. I am unsure about the proper setup when using a client program like mine to send commands to the C3 Bridge.
I apologize for asking a question not directly related to RoboDK, but I would greatly appreciate any response. Thank you for your continuous support.
Best regards.
