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Unread 13-04-2011, 19:03
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Mark Sheridan Mark Sheridan is offline
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Re: Minibot climb rate

Hey Bill

Perhaps there is wheel slip in the beginning of the climb, thus prolonging the acceleration in the beginning of the climb. 0.83 lbs is a lot of friction for the minibot. My guess is the the friction is lower and the minibot can accelerate quicker, but slippage losses in the beginning of the climb slow down the time. It overcomes the slip when motor toque is lower and the rpm higher, thus higher up on the pole. From here is starts accelerating with its full potential. Overall it appears to accelerate the entire length. It would be like pushing (or distorting) the velocity curve to the right.

On our revised minibot, it appears to slip a bit in the beginning but accelerates quickly after it. We run a 2.5 pound minibot with a 3/8 od wheel. It climbs in about 1.5 seconds. We are defiantly running higher magnets forces then yours. By increasing the magnet force, you can prevent wheel slip and prevent the robot from flying off.

I will see if your numbers compare well to my calculator later tonight.