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Unread 14-02-2016, 21:12
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Ether Ether is offline
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Re: Two Motors on the same mechanism: risks and mitigations

Quote:
Originally Posted by MisterG View Post
is each of those four blocks is a separate PID
They are separate closed-loop controllers. You can use PID if you like.

Block#1 (the top one) and Block#3 are identical (but separate) and should have similar tuning parameters.

Block#2 and Block#4 (the bottom one) are identical (but separate) and should have similar tuning parameters.

EDIT: Get one side working by tuning Block#1. Then use the same type of controller (and gains) to drive Block#3. Then add Block#2 and Block#4 and tune them to make the sides synchronous, using the same gains in each.

Quote:
with sp being the command and pv being the feedback?
Yes. sp is SetPoint (command) and pv is ProcessVariable (feedback).

Quote:
Did you just come up with this now or is this a scheme that you have known about for some time and if so do you know of any cases where this has been used successfully?
Hat tip to Jared Russell.

Lengthy discussion at this thread.

Here's a simple method for getting a nice smooth x(t) motion profile (if smoothness is desired).




Last edited by Ether : 14-02-2016 at 21:32.