Rookie Team 2582 with a problem... Please Help

[RoboGeek99]

We seem to be doing pretty well for a rookie team because we basically have a driving mechanism that kinda works but has 2 problems. First, the gearboxes work but when we hook them up only one side works and the other just kinda starts then stops and continues to do this until we cut the power. Second question how can we mount and construct a tensioner to mount to the chain in order to keep the chain from slipping off the sprocket from the gearbox (we have a 4-wheel drive) Please help us

[Taylor]

To answer your second question, we've had great success with floating tensioners from McMaster-Carr. They're not the cheapest things in the world (about $33 each plus shipping) but they work pretty well. Page 1010 of the catalog, and online as well.

[lukevanoort]

I can't think of what your power problems might be, but I may be able to help with the tensioners. This is what my team ran in 2006. Personally, I think this design was our best; it was definitely much better than our 2007 ones (our 2008 tensioners aren't fully made yet, so I don't have an opinion there). The u-bolts on the 2006 machine were easy to adjust and simple to make, in addition to being relatively cheap. For the actual idler sprocket itself, in 2006/7 we used ball-bearing steel idlers from McMaster-Carr, which worked nicely; however, they were kinda heavy for their function. So, this year we have aluminum ball-bearing idler sprockets from AndyMark, which only cost about $2 more and are a little larger, but weigh significantly less (sorry, I don't have hard numbers, we weighed neither the old nor the new idlers).

[Steve_Alaniz]

Originally Posted by RoboGeek99

We seem to be doing pretty well for a rookie team because we basically have a driving mechanism that kinda works but has 2 problems. First, the gearboxes work but when we hook them up only one side works and the other just kinda starts then stops and continues to do this until we cut the power. Second question how can we mount and construct a tensioner to mount to the chain in order to keep the chain from slipping off the sprocket from the gearbox (we have a 4-wheel drive) Please help us

First question is, Where is the problem? Is it with the gearbox or the pwm running the motor? Have you swapped PWM connectors and see if the problem follows? Does the problem start immediately or does it start when you move the joystick?
My first impression is that this is a programming error. The mixed channels are in PWM13-16 for single joystick control on the default code. Where do you have them plugged in?

Steve

[Alan Anderson]

Originally Posted by RoboGeek99

First, the gearboxes work but when we hook them up only one side works and the other just kinda starts then stops and continues to do this until we cut the power.

My first guess is that you have a mechanical binding issue that's causing the motor to pull too much current and trip the breaker. After a few seconds, the breaker will reset and it starts all over.

My second guess is that you've connected the Victor speed controller backwards. Make doubly sure that you have the power from the breaker panel and the wires to the motor going to the proper terminals.