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Unread 10-02-2005, 10:53
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What would Dave do?
AKA: Peter Kieselbach
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Re: 2005 Motor Information

Quote:
Originally Posted by HPA_Robotics_13
I think it was pretty much a lack of understanding.

Just to make sure I understand: The "stall torque" of a motor is the torque it provides (or the torque it takes to turn it) when the motor is not moving. So if I am to take a motor that is not hooked up to any sort of power source, the torque I apply to force the output shaft to rotate is that motor's "stall torque."

Thus: The reductions on my robot's FP system are such that with a full load (a tetra at the end of the arm) and no power, the system does not move. This means that I am putting no load on my FP motor when my arm is stopped at a 45 degree angle. I am producing no heat! This means that I do not have to worry about overheating my motors, because I have done such a large reduction on my system.

Does this all sound valid?
Sorry, but Stall Torque is the torque developed by the motor at the specified supply voltage with the rotor held stationary. Another way to look at it is the torque load applied to the motor which causes its rotation to stop (stall) when energized.

If you are relying on the de-energized motor magnetic torque (and drive friction) to hold your arm stationary, beware of unexpected loads caused by inertia, other robots, etc. and of changing system losses (gears wearing in, etc.). You may find your arm starts dropping at unpleasant times - like when the buzzer sounds and you just got clear of the tetra you capped with.
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