View Full Version : chapita motor problems

06-04-2002, 11:55 AM
We are entering our third year as participants in the FIRST competition. We're looking at the possibility of using the chapita (sp) motors as the main drive source for our 'bot, but we are having difficulty with the motors pulling too much current and popping the 30amp fuses. We are using a chain drive system with a 12 tooth drive gear directly attached to the motor shaft to a 20 tooth driven gear. This is attached to an axle with another 20 tooth gear which is in turn attached to our wheel shafts. Any suggestions? Any help would be greatly appreciated.:confused:

Mike Schroeder
06-04-2002, 10:14 PM
Hey, well all i remember from our robot is that we used the chiwapia motors and a 60 amp breaker if you need more info contact Wayne C. on the cd forums

Andy Brockway
06-05-2002, 10:16 AM
It sounds like your gearing is too high.

Look in the White Papers for Team 716's design. It uses the cluster gear to bring the rpm's to something more manageable.

The motor turns at 5,500 rpm free speed.

The gear ratio's are:
motor/cluster = 9?/44
cluster/output gear = 16/60

This gives an output speed of 300 rpm. We geared this 2:1 giving 150 rpm to our 9" dia Skyway wheels.

You can use chain to attain the same output directly from the motor but it takes more room.

Good Luck