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Unread 18-11-2001, 13:43
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FRC #0177 (Bobcat Robotics)
Team Role: Engineer
 
Join Date: May 2001
Rookie Year: 1999
Location: Hebron, CT
Posts: 110
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Re: Simply Friction

Quote:
The electric motors exert a constant force relatively speaking on the system.

Basically, as the speed of the robot increases, the internal friction (friction in the gears/sprokets/bearing) increases directly proportional to the increase in speed.

This is more or less backwords.

The losses in the system will not actually increase that much as the robot accelerates.

The force (torque) output from the motors will decrease as the robot accelerates.

There is a limited amount of power available from the motors. The power from the motors is equal to the product of the torque they provide and the speed at which they are turning. As the RPM's of the motors go up, the amount of torque they can supply goes down. Eventually, the available torque is reduced to the point where it is equal to the frictional losses in the system and the robot stops accelerating and continues on at constant speed.