Autonomous wheel chocking bot

Working on an engineering senior design team creating a robot to chock wheels. Currently sourcing two motors for differential front drive. Open to either direct drive or a belt drive but prefer direct for simplicity since it is a proof of concept not an actual product.

I did calculations that we need 1 ft-lbs (1.355 Nm) of torque at each wheel. Its pretty low speed at about 3 ft/s and needing to reach speed at about 2 seconds. Only needing an RPM of about 140.

I am looking at the $69 Odrive dual shaft motors D5065 270KV. Would get two of them for left and right front wheels. They are rated at about 1.46 ft-lbs (1.99 Nm). But then I see the de-rating curve. How true is this data for this curve? The motor for us would only have a faceplate no casing so it would be open to the air. Does it really take a 0.5x de-rate in torque?

The bot will likely weigh around 100 lbs. Do you think these motors will provide enough torque to get this guy moving on flat ground? I believe my calculations are correct, but just am trying to avoid spending my sponsor’s money on two motors that dont have enough force behind them!

Any insight is appreciated.

Grab a couple of D5065 motors and a pair of inexpensive Vex Planetary gearboxes with 1/2" shafts. No problem :slight_smile:

And yes, the thermal derating is pretty serious on these (and all other hobby grade motors)