Spindle orient PID tuning [re-solved, yay]

Thanks Robert.  While I'm waiting for PCW to get back I'll have a go with it - without the lincurve & limit2 - and see how it behaves with FF1 = ?

What's the worst that could happen?

FF1 will not work with step inputs to the PID (as the orient component outputs currently)

PCW wrote:

FF1 will not work with step inputs to the PID (as the orient component outputs currently)
 

 

 

Ok, I need a limit2 in between pin.N.something and pin.N.something-else.

And the limit2 needs some max, min, and maxv values.

And something to turn on/off the limit2 at some condition.

If I get a mostly working config I can eventually digest how the parts are working together, but since I don't know where to start I'm kind of stuck without an actual example.  I'm still at the monkey-see, monkey-do stage with this sort of thing.

EDIT  how does this look?

net orient-command   <= orient.0.command
net orient-command   => limit2.0.in
net orient-command-limit   <= limit2.0.out
net orient-command-limit   => pid.0.command
net orient-limit-switch  <= pin.0.mystery
net orient-limit-switch  => limit2.0.load

setp limit2.0.min   = ???
setp limit2.0.max  = ???
setp limit2.0.maxv = ???

Basically what you want is for the orient motion to be a simple trapezoidal motion profile
so that even without any feedback, (and mainly just feed-forward) you end up at
approximately the right endpoint. This means, much less is asked of the feedback
so you don't need as high gains and the integral term will not get a massive windup
as you get with a step motion command.

Thanks for the explanation, that was rather helpful understanding the goal and process.

Unfortunately, without details or starting values I'm not able to accomplish this.

Actually limit3 is needed
Starting values for the bounds should be pretty easy to set
maxv is in RPS and maxa is in RPS/S