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most important about motors
The most important about the electric motors we get from the kit is the speed torque curve. A lot of people don't understand how important this curve is, but you should really pay attention to it. Especially since woodie mentioned it a lot during kickoff.
What's so important about it is that it describe the behavior of a motor under load. Not what happen when you gear the motors or whatever other situation people came up with (which, by the way, was quite interesting to hear how people explain the speed-torque curve)...
So basically, the speed torque curve explains how a motor will react under load. The more load it face, the slower it goes, until the motor stall out. At no load, the motor is spinning at free speed, and under extremely amount of load, the motor is stalling and not spinning at all. And of course, as the load increase, the current it draw increase too.
So why is this important, well, it's because using this curve, you can figure out where are the most optimal places on the speed torque curve you want to me in. Either near the power peak, or the efficiency peak. And you do that by gearing down on whatever component you are using that motor on, and choose how much load it's going to reflect back to the motors. If you have a huge gear reduction, the motor will feel so little load that it might run near free speed... On the other hand, if you aren't gearing the motors at all, they will face all the load and stall if that amount is too big for them to take.
The amount of torque you can get out of is the range of torque from the speed torque curve, from zero to... well, not stall torque, because that's when you draw so much current that the circuit breaker will trip. Just look at the graph and figure out highest torque you can get before breaker start tripping, and multiply that with the gear ratio.
That's the range of torque your component will provide at different situation... Under load or no load. Say it's an arm, the arm will be pushing harder and harder within that range, before it start tripping breakers or start stalling the motor.
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