Thread: Torque Calculation/Determination-Urgent
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Unread 13-04-2014, 11:33
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Re: Torque Calculation/Determination-Urgent
Good questions. Maybe the engineers from VAX and CTRE can answer for their respective motor controllers.

There's also the question of the 775-18 spinning at 13000*2 = 26000 RPM. Can its rotor, fan, and the bearings handle this? And even if the the motor leads are open-circuit (zero generated current), how much load does the fan put on the MiniCIM at that speed, through a 20:1 gearbox?



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Good point on the fan - I had not thought of that. The 26000 RPM is only 33% higher than the 19,500 free RPM at the rated 18V. The robot will not be at this velocity very often or for long so I think there is sufficient margin.

I assume that the ESC have flyback diodes, so it will never truly be open-circuit. I am not sure what load that will impart on the MiniCIM. If the ESC blows, it expect it will be the flyback diodes that smoke.