Connecting UR Cobot over Modbus TCP

Hello,

I am working on connecting a UR5 cobot via Modbus TCP and extracting data in Ignition (v.7.9.7) to determine the number of times the robot enters protective stop.

As of right now I’ve managed to connect the cobot to ignition and extract data, but if it’s reconnected (either by restarting the cobot or accidentally disconnecting it by removing the Ethernet cable) it will enter a loop where it’s state fluctuates between Connected/Disconnected. The only solution that I have at the moment is editing the tags in designer (open tag, press ‘ok’), which seems to help reestablish the connection, but that has to be done manually. Is there a way I can avoid that by using an automatic reload tags function after a set time amount (5-10 minutes) or is there another way of solving the root problem?

Thank you,
Stefan

did you ever figure out a solution for this? we are having the exact same issue and band-aid fix with a UR10E cobot over here

it still sends modbus to the HMI it has connected to it normally , The Cobot is only blocking the data to ignition specifically

Never played with a UR10E however you could maybe set a periodic script of tag.configure etc, but not actually make any changes, or do disable the tag then reenable

https://docs.inductiveautomation.com/display/DOC81/system.tag.configure

We've had the same sort of issue with our UR5 with Ignition 7.9, and 8.1. Sometimes it's a problem, sometimes not. Sometimes I can get the problem to go away by simply launching Designer and having it actually start communicating with the Cobot.

This is interesting as I am starting to deal with them more.

Maybe you can monitor the device connection and run something to refresh it when it happens.

I'm running into a similar Connected/Disconnected issue but it happens immediately on configuring the device which doesn't allow me to ever view data at all. Has anyone run into this issue and resolved it?

EDIT: I have been able to establish a connection by first adding a tag, then changing its OPC Item Path after being created. This seems to switch the device to a Connected State, even if the original OPC item path was a valid. For example, if I add [UR]HR0, then switch it to [UR]HR1, the state becomes connected. If I change the path back to [UR]HR0, it remains connected. Any edit to the OPC-UA Device Settings or restart of the robot controller puts it back into the Connected/Disconnected Loop. Just simply editing the tag and pressing okay or disabling/enabling the tag doesn't seem to restore communication.

Can any IA driver gurus speculate why this may be happening?

For anyone reading this in the future, after a call to tech support and trying a few different things we found that editing the Tag Groups OPC Settings Data Mode to "Polled" fixed the issue.

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That sounds promising. Can you please explain how to get to that point? I'm still very new to Ignition and can't seem to find a place to change Tag Groups OPC Settings Data Mode to "Polled". I'm sure I'm not looking in the right places.
Thank you

OPC Settings
Data Mode This mode dictates how OPC values are obtained. The default mode, Subscribed, is preferred because it is more efficient than a read.

Subscribed
All OPC Tags in the Tag Group will be subscribed according to the Tag Group rate. Values will come in asynchronously as they change.

Polled
Tags will not be subscribed, but will instead be synchronously read each time the Tag Group executes. This operation is less efficient, but allows more precise control over when values are obtained. This mode is particularly useful when collecting data over a slow or expensive connection for display. When combined with the one-shot execution mode above, and a static Tag tied to a momentary button, it's easy to create a manual refresh button on a screen that pulls data on-demand.

https://docs.inductiveautomation.com/display/DOC81/Tag+Groups

That worked, thank you