Side of Drives Giving Out

[LeelandS]

Our robot has been having a bit of a problem as we have been practicing for the Rah Cha Cha Ruckus in a few weeks. We will go to drive up the bridge, get up a little ways, and a side of the drives (commonly the left, occasionally the right, sometimes both) will just give out. They stop working and the robot spins backwards with only one side of the drives working. I'm looking for possible causes, as we have not clue where to look.

Here is the set-up. Each side of the drive is powered by 1 CIM motor, through a CIMple box. We have a wide orientation robot with two wheels on each side, so this set-up is chained to both wheels. My hitch with giving details is that I did not help design or build this robot. This is the 2012 robot of a team I joined in July, so I wasn't part of the design process.

I speculate (and I am by no means a mechanical engineer or an expect on motors) that the CIMs can't handle the load of going up the bridge and just shut off temporarily. We maintain communication with the robot, and after a few seconds can continue driving around. I am lead to this conclusion by that fact, and that the robot has no issue driving around on flat group. Since there is only one CIM per side, it's a hefty load, even for such a tough motor.

If there are any details that might be pertinent to the discussion, let me know. I know this has been a persistent problem (it occured during testing over the Summer). The next time I will be able to see the robot work will be Thursday morning, so I will be able to gather data and look for anything else based on feedback.

Any help would be appreciated. Due to lack of mechanical mentor support, I don't think any changes can be made. But I would like to know what the issue is. It will certainly influence how we play at Ruckus. Thank you in advance to any who are willing to offer advice.

-Leeland