Thread: 6WD vs 8WD
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Unread 06-01-2011, 11:43
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Re: 6WD vs 8WD

Quote:
Originally Posted by JamesCH95 View Post
Good point, and well worded.

However, consider that the driving force (i.e. output torque of the motors) decreases with speed. At some speed the motors will lack the torque required to spin the wheels, barring extreme cases. At that point, the situation will become the F=ma situation we all know and love and the lighter robot will be able to accelerate faster.

Another interesting tidbit is that the wheels' coefficient of friction may not be constant, but rather vary with contact pressure. Assuming that the coefficient of friction is constant the heavy and light robots will accelerate at the same rate in a friction-limited case. However, if the tread/playing surface is sensitive to contact pressure then the lighter robot will have the advantage, all else being equal.

Also note that a drive-train does not require power to break traction, but rather requires torque, specifically torque on the drive wheels.
Good points (especially the last one, I have to be more careful about my technical diction around here ).