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Collmandoman
10-03-2005, 13:27
Would I PID controlled arm still function when the pressurepad is deactivated?
sanddrag
10-03-2005, 13:41
I doubt it. I believe the robot controller is put into disabe mode which makes it so nothing can operate.
Dave Scheck
10-03-2005, 14:32
My understanding was that when the pressure pad was deactivated, the disabled bit gets set. When that is set, the robot is disabled which causes the outputs of the RC are held at neutral (127). Your PID loop will continue to run, however, there will be no output to your motors. Be careful that your integral component doesn't wind up while you're disabled...that could make for some interesting results when the pad was reactivated :ahh:
Alan Anderson
10-03-2005, 14:46
When the robot is disabled, Victors will go to neutral, and Spikes will turn off (both FWD and REV outputs go to ground). Note that this can easily cause undesired actions if you're using any Festo valves in your pneumatics!
ConKbot of Doom
10-03-2005, 16:53
When it is disabled, is it really outputing neutral (127) to the victors, or is there no signal?
I know that with motor controllers it isn't really that big of a deal, but if there were say, a servo controlled latch for an arm. That could make for an interesting situation. Or servos for shifting transmissions...
Ryan M.
10-03-2005, 20:20
When it is disabled, is it really outputing neutral (127) to the victors, or is there no signal?
I know that with motor controllers it isn't really that big of a deal, but if there were say, a servo controlled latch for an arm. That could make for an interesting situation. Or servos for shifting transmissions...
It actually sets it to 127.

And to answer the original question:
The program continues to function, meaning your PID will still be working. However, any output is ignored by the RC. This should be fine though, because the errors will just accumulate and be corrected for when the disable is turned off.

If you're asking if you can still move the arm, the answer is no. :( Sorry.
Anthony Kesich
10-03-2005, 23:30
If you're worried about the PID building up, you can disable your algorithm while the robot is disabled.

There is a bit called disabled_mode that is 0 of the robot is running and 1 if its disabled. If you want, you can tell the PID only to run if disabled_mode == 0, other wise, just leave it. This will keep your integral term from building up and making the arm be crazy.

Hope this helps.

-Tony K