If our system powers down for any reason we have a communication issue with our Cognex camera. We are running the camera with the URCaps plugin. Maybe this is a question for Cognex, but figure I would try my luck here…
We typically run the system “Remote”. So then the operator has to jump back into Manual Mode > Installation > URCaps > Cognex > Refresh the connection. The connection is shown as Green, but as soon as the refresh is performed the system operates as normal without issue.
The error message before doing the refresh is the following;
XMLRPC: Failed with exception unable to transport XML to server and get XML.
response back. libcurl failed to execute the HTTP POST transaction, explaining:
Failed to connect to 127.0.0.1 port 33004 Connection refused
Program node: CCX result —CameraPose
Program node type: Cognex Camera Pose
Error position: line 99
URcap: Cognex In-Sight Robot Guidance - Cognex Corporation
Yeah that’s probably going to be a question for Cognex. I’ve experienced several URCAPs that are not very good at handling loss of power/comms. Comes down to how they’ve written their CAP and how fault tolerant it is (or isn’t).
It was a decent pain overall, but I was able to get everything to work. It would have been nice if the new version (1.3.1) of the Cognex URCaps wasn’t completely incompatible with the older version (1.2.2). I had to go back to the older version, Copy/paste all my programs into new NON-Cognex URcap programs on the robot and then update to the new URCap version and then insert the new URCaps program structure into that program and paste everything into its correct area.
Luckily we only had like two main programs running otherwise it could have been a major headache.
I noted to Cognex that their URCaps were not at all backwards compatible and the headache that it caused due to the program just not able to load at all.
WOW, that sounds like a lot of work… Unfortunately, we expect a lot from certain companies that have a good reputation in the industry, but then we have to solve ourselve the problems. I am having problems with my application because of the accuracy of the teachpoint.
I have to keep a distance of 650 mm between my part and the camera and the robot does not drive always to the teach point with the accuracy that I need, If the part if below the camera, everything is ok, if the part goes like 3 cm to the right or left, the accuracy goes down. Maybe you have an advice for me. I´d be very greatfull to you.
I don’t really know enough about your application to try to give a good response.
What do you mean that the robot does not always drive to the teach point? The robot should go to the same point unless you have a blend enabled on it. You can also add a wait command at the point to ensure the robot is stationary (or using is_steady() code) at your point until the next command is issued.
Image we have a ruler and my pick point is always the 10 cm mark, well the robot drives to 10 cm with great accuracy if the foto was taken when the part was directly under the camera,
But if I take the foto and the part was moved a couple of cm to the left of right and not directy under the camera, the robot misses the 10 cm mark and drives to 8 or 12 cm that means the accuracy of driving to the teach point goes down.
Hmm… Not 100% on an answer. Are you calibrating your Camera and correcting for possible lens distortion? I could see those possibly causing some issues you are referring to. If you’re not well calibrated the robot and the camera may be giving unwanted results.
I am only doing the calibration of the URCaps from Cognex like in this video https://www.youtube.com/watch?v=eTpo2FXoSd8&t=1185s. My application looks like that one but the distance between my camera and the object is 700 mm. I guess in the video it is not as much.
I don´t know if it is possible to mix somehow first the calibration for lens distortion and then the cognex one. i am kind of a lost in this topic
I’ve found the problem. After I did the calib, i changed the TCP and that is not allowed. That the reason why he was going to the wrong placw the whole time. Thanks again for taking time to answer me
Glad you were able to figure it out.