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chip updates: interesting concepts that come from not designing something [funnies]

So here's an interesting. What I realized is that the motors/controllers are being limited to 14% of maximum output speed/power? What that means is the max speed of the motor is now 0.14*(5676rpm) = 790rpm.

That means the average torque being outputted by the motor is a little above 2.0 Nm according to the above graph. That means the output torque of the gearbox is roughly 200 Nm max?


At least that's what I think makes sense. The total output power is 14% of the maximum output power. Which means the total torque*speed is 14% of the possible max. So that's 406W*0.14 = 56.84 watts.


So at the maximum speed we can now achieve (which is 790rpm or 82rad/s) that's 0.693 Nm maximum output torque from the motor. That's 69.3 Nm of max output torque. Maybe that makes the most sense.


Let's go with the 69.3 Nm torque just so we don't expect the leg to do more. I wish there was a way to directly measure the output torque the motor is outputting at any given moment. I don't know enough about the torque/current/voltage relationship of a brushless motor so I'll do some more research on that at some point so maybe we can measure it but I don't know enough about that right now to figure out the relationship.


But what this does tells us is maybe we don't need as big a gearbox as there is on there - enough reduction to get the gearboxes back in the green region of operation as an overall design?


#updates #omgrobots

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