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IIRC, the ROS UR controller runs at 200Hz and we’ve had arms crash when they run much slower than that.

The website claims “30hz polling rate”, “2ms latency”. Not sure if that is a best case or just for that demo.

Crash? The software, or physically? A 200Hz as a min control loop rate seems on the fast side as a general default, but it all depends on the control environment - and I may be biased as I've done a lot more bare silicon controls than ROS.

I'm guessing running a 200 Hz command rate on an e-series UR which uses 1 kHz internally will give you a protective stop?

Physically crash. When we would block the control loop at all (even down to 100hz), we would get errors and then occasionally the arm would erratically experience massive acceleration spikes and crash into its nearby surroundings before e-stopping.

Re: Other comment. Yes, this was with ur3e s which by default have update rates at around 500hz.

> The website claims “30hz polling rate”, “2ms latency”. Not sure if that is a best case or just for that demo.

This is just example cases but in fact it can go as high as you want as long as your hardware allows it

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