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0 pointsicegreentea24y ago0 comments

Yes, this stuff is nice.

But it is worth noting that these control loops can often have some sort of memory, so you normally need to test over multiple cycles - you usually have a test vector to load in, and watch for the response vector.

Trivial example would be if you had a PID controller implemented into your main loop. Your main loop would be storing the integral and "previous" error term.

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bagels4y ago

Equivalent to handling an additionaanl sensor input and an additional output, no?

icegreentea2OP4y ago

Yes, you could in principle convert any memory within a given loop into a separate unit. You just gotta pick between the tradeoffs between having more I/O and software/hardware units, versus having more memory within specific software/hardware units.

You just gotta find a balance that works for your requirements and constraints. In my application (it was medical devices), we found that stateful loops fit nicely.

EmielMols4y ago

True, but you do want to test the emergent control system.

jcims4y ago

That's the irony of closed loop control systems. They appear to be simple but the emergent behavior, particularly when there is a hierarchy of control loops, is incredibly complex.

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