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Re: Top Speed
The Wildstang robot has been designed to go about 7 ft/s top speed for the past 5 years. We have used 2 drill and 2 Fisher Price motors for the drive for the past 3 years. We have convinced ourselves that with the power of these motors, this is about the optimum gearing for speed versus torque if you do not have a shifter (we never have done a shifter – why would be the subject for another thread). Anyway, at this gear ratio, we can accelerate a 130lb robot pretty quickly. And when you have “crab” steering, this is about as fast as you want to go for control reasons. We use another technique to reduce the sensitivity of the controls for “fine motor skill” maneuvers – we cut the PWM output to the motors in half when the trigger on the joystick is not depressed, and set it to full PWM output when it is depressed.
I will say that if we decided to use more powerful motors (the Chips instead of the FP’s) then we could bump up our top speed accordingly. This is why 25’s Evil Machine, which used 6 motors for their drive, was effective at a higher top end speed. But yeah, at those speeds, the drive control sensitivity is very high and thus difficult to control the robot.
Raul
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Warning: this reply is just an approximation of what I meant to convey - engineers cannot possibly use just written words to express what they are thinking.
Last edited by Raul : 04-12-2003 at 07:37.
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