JVN Build Tip: Mechanism Loading

[dtengineering]

Originally Posted by JVN

CIMs are champs -- do whatever you want, the breaker will trip before the CIM even flinches.

This is (as you'd expect from John) a great write up. There is one conditition, however, where our CIM's have become hot enough (outer case over 60 degrees C) that I started to worry about them. That was using them as drive motors in repeat practice matches. One year we were through tech well before most other teams and the field crew wanted robots on the field to test their systems and make sure everything was "broken in". Our drive team was MORE than happy to oblige. At some point (on the third battery change, if I recall... we'd been going at full "match" power for over half an hour) I mentioned to one of the students that we should check the motor temperature.

The student replied "Ouch!" We grabbed our IR thermometer and I can't remember exactly what the temperature of the case was, but it was hot enough that even if the CIM wasn't flinching, I was. It took about half an hour to cool down to the point where I felt good about firing the motors back up again.

Now, the good news was that the CIMs were still fine, so I'm not disagreeing with the quote. But there may be occasional circumstances where even the mighty CIMs shall succumb to heat.

Of course, if you use them in an arm, and counterbalance the arm like John is suggesting (that's kind of the point of the whole post) then you shouldn't have a problem.

Jason

P.S. If you want to see some cleverly counterbalanced arms, just check out a VEX tournament.

P.P.S. Oh, the many benefits of being through tech at 9:00am!