pic: 2008 FIRST team 1001

[Qbranch]

Originally Posted by Woody1458

Also as far as speed you only get 50% of your output twards speed, the rest of the power goes towards the wheels pulling away from each other.

Well, thats true, IF you want one of the flat sides of the robot to be the front. There's nothing saying you can't pick a corner and have that be the 'front' of the robot when driving.

Originally Posted by Woody1458

Being on all Omnis people will be able to push you around with nothing you can do about it.

True, however with a small (1 square foot or so) robot on a omnidirectional drive train of some sort, I doubt many robots will be doing much catching up with you. Remember, the absolute maximum intermittent duty horsepower four 2.5" CIMs working together can produce is 1.8hp at the shaft. This means, if you have a 120lb robot and you want to travel at 15 ft/sec, it'll take you 0.42 seconds to reach that speed. Now, if your robot weighs, say, 30lbs (beleivable for what is essentially a square with motors, transmissions, wheels, and all things required for the FRC controller + drives), and we accelerate to 15 ft/sec with the same energy input, we reach the speed in just 0.11 seconds. True, both of these robot assume perfect traction, a battery that never dips below 12vdc, and a victor drive that can drive the motors to their maximum Wo state (about 67 amps), however the point is still made: little robot, accelerates and makes turns MUCH faster than any other robot could hope to.

But, yes, if you got into a pushing match you'd surely lose... not than anyone could get you in one anyhow.

Sparky 1001: *chuckle* nice picture. I'm not sure what your team really is building... but if you are going towards building the smallest FRC drivetrain robot you can, more power (or acceleration? ) to you. But uh... I think just using vex might get a little outclassed.

sooo... what are you all actually building? I'm curious now!

-q