Thread: Drive Trains
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Unread 01-04-2008, 14:07
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Re: Drive Trains

Quote:
Originally Posted by neoshaakti View Post
what are the different elements of a drive train, and how do teams maximize each elements performance.
Leaving the driver aside for now....

The first element is the motors. A fast, powerful robot will use at least two CIMs per side, or if it's a Mecanum or Omni drive it will have one CIM for each of the 4 wheels. For added power some teams add a Fisher Price motor to each side also.

The second element is the transmissions. They need to be strong, reliable, and provide the correct gear ratio(s) for the way you plan to play the game. Multi-speed transmissions will give both good low speed pushing ability and maneuverability, and high speed for moving quickly across the field. Designing and building your own transmissions is quite a challenge, some teams meet this challenge well, but most decide to either use the kit transmissions or buy good quality transmissions such as AndyMark offers. Maintenance is an important issue, gears need lubrication, bolts need to be kept tight, etc.

The third element is connecting the wheels to the transmissions. Some use direct drive, some use gears, most teams use chains, and a few use belts or "tank treads". The drive system needs to be well made, have the correct ratio to play the game well, include necessary tensioning methods, and be easy to repair if needed.

The fourth element is the wheels. The kit wheels are good enough for many teams, but there are also many different styles and sizes of wheels available from different sources. Many teams that have CNC machining capability design and make their own wheels. Important considerations are wheels strength, tread friction and life, and maintenance. Good wheels will provide high traction and the tread will last at least for an entire regional event, and the wheels won't break or come loose or otherwise fall apart. Also there are several types of omni and Mecanum wheels available, and some teams make their own wheels.

I won't talk about crab or swerve drives, they are a special category and require quite a bit of research to figure out how to make them work well.