Running a Window Motor with both a spike and a victor at the same time

Hello from team 253,

We are having trouble with a window motor running off of a victor running full power. We would like to run the motor full speed forward with the spike and then at roughly 30% power in the negative direction with a spike. Is this possible? I mean is it legal? Thank you for the help.

If you need a drawing ask me, I can post one.

Thank you,

Shane

Spikes have three speeds: Full forwards, full reverse, off.

If you’re running both a Victor and a Spike to control a single motor… I suggest using ONLY the Victor if you need variable speed. I can’t find a rule saying it’s illegal, but you’ll have a much more difficult time passing inspection than if you only use one (and the wiring… you might get into trouble with altering the wiring pathways).

What trouble are you having with the window motor, exactly?

Hello!

Our window motor was running off of a spike to lift and drop a big claw that sits in front of our robot to pick up the ball. We were using the window motor with no problem for the past two weeks with no problem and now (this week) after not changing anything our motor can not lift the ball when we have it in our claws.

We are not sure what to do about this and we are looking for any help.

Thank you!

Shane

P.S.
This is my real account.

The Window motors contain an internal PTC circuit breaker - if they get too hot the circuit breaker will open the connection (and stop the motor) until the motor cools down.

Check everything to make sure nothing is binding; if there is nothing obvious then it is likely the Window motor is simply struggling with the task. The Window motors only have a peak power output of 20 Watts, which is one of the weakest FRC-legal motors.

In this case, you should investigate to see if you can use a different, more powerful motor to accomplish this task.

You’re connecting the output sides of a Spike and a Victor together? If so, I’m pretty sure that’s a bad idea. A couple bad lines of code and you have both devices turned on with opposite polarities connected.

A Victor should have no problem running a window motor at 100% duty cycle, assuming you have calibrated the Victor. You have, right?

I think that since the spike is running while the victor is off the victor will hav 12 v applied across the output side. This would be functionally similar to plugging it in backwards which can fry them.

Note that the Denso window motors have pins (which have been expressly allowed in the past and one should consult the current year’s rules to confirm this is still the case) that will lock the motor with the torque of an arm with some weight to it. We ran into the same issue with an arm design back in 2011, removing the three pins in the plastic housing where the motor meets the gearbox solved the problem.

http://www.chiefdelphi.com/forums/archive/index.php/t-91768.html

R30 The integral mechanical and electrical system of any motor may not be modified. Motors, servos, and electric solenoids used on the ROBOT shall not be modified in any way, except as follows:

C.The locking pins on the window motors (P/N: 262100-3030 and 262100-3040) may be removed.

Found it, emphasis mine.