RTDE protocol incompatibility?

Technical Questions Robot Communication
1

Hi everyone,

I’m integrating the RTDE client in a python daemon to read the robot’s pose.
I could already modify the samples provided to read it successfully in the simulator using the software version (3, 4, 0, 285).

When I try to run it in a real robot (version 3.3.4.208), the RTDE client cannot negotiate the protocol version. The samples use protocol v2, so I changed it to 1. When I do so, I get the following error:

Traceback (most recent call last):
File “/usr/lib/python2.5/threading.py”, line 486, in __bootstrap_inner
self.run()
File “pose_daemon.py”, line 47, in run
if not con.send_output_setup(output_names, output_types, POSE_UPDATE_RATE):
File “/daemon/rtde/rtde.py”, line 125, in send_output_setup
result = self.__sendAndReceive(cmd, payload)
File “/daemon/rtde/rtde.py”, line 202, in __sendAndReceive
return self.__recv(cmd)
File “/daemon/rtde/rtde.py”, line 245, in __recv
data = self.__on_packet(packet_header.command, packet)
File “/daemon/rtde/rtde.py”, line 188, in __on_packet
return self.__unpack_setup_outputs_package(payload)
File “/daemon/rtde/rtde.py”, line 289, in __unpack_setup_outputs_package
output_config = serialize.DataConfig.unpack_recipe(payload)
File “/daemon/rtde/serialize.py”, line 177, in unpack_recipe
raise ValueError('Unknown data type: ’ + i)
ValueError: Unknown data type: OT_FOUND

I don’t know what I’m doing wrong. Does someone know what to do to get the protocol version 1 working correctly? Do I need to change something in the XML configuration file?

Thanks in advance

EDIT: I just read the release notes for SW 3.4 which mention the upgrade to protocol version 2, and that the samples were upgraded. Is there some sample code for version 1 around?

1 Like
2

We would suggest sticking to protocol v2 since this was introduced in SW 3.4.

1 Like
3

Thanks! I will take that into account!

4

I am also working on getting RTDE working. Like jubeira, I have a working version on the simulator against UR version 3.4 protocol version2, but I can not seem to get a working sample for protocol version 1 working. My robot is running version 3.3. How much work is it to upgrade the robot from 3.3. to 3.4?

5

Upgrading simply requires for you to download the software (.urup file) from the Support site, place it on a USB drive, plug the USB into the robot, and navigate to Setup Robot > Upgrade,

This should also be elaborated in the manual.
UR Software download

6

Thanks JBM. I will upgrade the robot and continue to work against RTDE protocol 2.