Quote:
Originally Posted by JoesephWhite
Could you explain to me why we should you the Toughbox vs. the CIMple?
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The CIMple Box's reduction is only 4.67:1. This is fine in the Kit of Parts drives of 2011 / 2012, because they came with a chain reduction to further reduce the CIM output, but when you are direct driving you are locked into that gear ratio.
If we plug your drivetrain into
JVN's Mechanical Design Calculator*, your drivetrain has a free speed of about 30 feet per second (approximately 24 feet per second after friction and other losses). That sounds great, except that you'll never, ever get going that fast. Either you would spend the entire length of the field accelerating, or in this situation, you're so overgeared that you will probably trip circuit breakers just trying to move or turn. Basically, you don't have enough torque to move yourself.
The Toughbox Mini is a 2-stage reduction, so you have a lot more flexibility with your final ratio. I don't know if your team has the 2013 KoP Toughbox Minis (10.71:1 ratio) or the off-the-shelf ones direct from AndyMark (12.75:1), but both of those ratios are much better for 6 inch wheels. The former will give you a speed of about 10.5 feet per second after losses, which is a pretty good, fast speed for a robot that only expects to play a little defense, while the latter will give you a speed of 8.8 feet per second after losses, which is better for inexperienced drivers and more defensive play.
*The "right" answer to your questions would be explaining all of the math of drivetrain gearing to you, but it's near the end of Week 4 so I'd rather just "give you the answer" and have you look into the physics behind it when you have free time.