Multi Robot Control

I assume these are KUKA robots?

It depends on how you need them to coordinate. The usual practice is simply to create "collision zones," spaces where the robots would collide. If a robot is clear of that zone, it turns on a signal to the other robot(s). Before entering that zone, the robot checks to see if the clear signal from the other robot(s) is active, and if so, resets its own clear signal before entering the zone.

This can get a little complicated, though. It's not hard for a situation to arise where two robots both hit their "enter zone" logic at the same time (or within one I/O refresh cycle), see each others' Clear signal still active, and both enter the zone before seeing the other robot's Clear signal go inactive. So there's often some extra safeguarding that needs to happen here.

Now, if you need multiple robots to move together (say, cooperating to lift an object too big for one of them to lift alone), that requires a completely different setup. For KUKAs, this usually begins with RoboTeam and special connections between KRCs, and special programming and calibration to allow the robots to move as if they were one.

roboteam is used in applications where two or more robots move in a coordinated fashion... like sharing the load. most of the multi-robot cells do not use roboteam - even though several robots are in same space, they often work independently (not coordinated). they simply use zones and handshaking signals to prevent collisions.

Quote from emerald_geni

Thank you for your explaination. Is this the same logical thinking that is used perhaps for robots in automobile manufacturing.

It's pretty typical. GM, for example, has an entire complex programming standard written around this, including pre-written robot and PLC logic that all system integrators are required to use on systems for GM.

The basic concept is used everywhere.

Quote from emerald_geni

I get roboTeam is the Kuka varient but is the concept u mentioned applicable for other robot implementations as well in the industry?

I'm pretty sure that Fanuc and ABB have their own equivalents. The trick is that this either makes two arms part of the same controller, or makes multiple controllers act as if they were one controller. It only works with robots of the same brand and same software/hardware revision levels.

Frankly, it's such a pain to set up and use, most of the time it's not worth it. I've only ever seen it in situations where it was absolutely necessary.