I’m using a planetary gear set and I need to figure out the torque of the output. I couldn’t find anything that would measure the torque of a shaft (mostly the torque and efficiency of cortex motors). The only way I could think of how to do it for now is timing how long it takes to reach maximum s…

[image] DrewWHOOP: What you probably want to find is the stall torque Okay I’m going to do that. Also I’m assuming that I should still find acceleration speed but I should calculate torque with what Kmmohn said. Also does anyone know the stall torque of V5 motors? Edit: [image…

you can find it on the VEX website. I believe for the 100 RPM (red cartridge) it’s 2.1 Nm

He’s looking for the experimental values, not just the theoretical ones, I’m assuming. As was said earlier you can test this with a pulley, or, you can use an encoder and measure the rpm at the shaft, and then use the formula P=ωτ to find the torque. The power value is listed on vex’s website, I do…

Here’s an example test rig you could set up. Torque would be the length of the beam (from the center of the motor shaft to the point where it is pressing on the scale) multiplied by the scale readout. [Capture.PNG]

τ=FSin(θ). It’s multiplied, not divided

Right…thanks for catching that. (I’ve corrected my posts). Long day, and I forgot all my arithmetic when I took Calculus, and I haven’t used Calculus for 30 years, so I’ve forgotten that too :crazy_face:

Yea I’m looking for the experimental values because my gear set is semi inefficient and also thanks kmmohn for the CAD picture I was confused on how the setup would be. Also is that example for how to do stall torque or for torque (sorry I’m not good at words) I’m assuming stall torque because you…

Right, the set-up shown would be stall torque…or it might be the torque where your shaft starts twisting…be careful if you’re using a low strength shaft in a V5 motor!

I’m assuming that stall torque would be more helpful in pushing battles but torque would be more helpful when accelerating. But they both would go up with a gear ratio that increases torque.

How do I measure torque from a shaft?

VEX V5 General Discussion Technical Discussion

Hudsonville_Robotics October 15, 2020, 2:06am 24

I don’t mean to wake the dead but why not nudge 'em a little. This is a dyno article from 2017.