Pololu Robotics & Electronics
My account Comments or questions? About Pololu Contact Ordering information Distributors

Pololu Forum

DC motor 20D

I’ve purchased this motor Pololu - 100:1 Metal Gearmotor 20Dx44L mm 6V and I want to simulate a model for the DC motor in load. I really need the following parameters L - electric inductance and J - moment of inertia.
I can’t found this parameters anywhere and I don’t think I could calculate them, especially the electric inductance.
Thank you!


The inductance of our 6V precious metal brush 20D gearmotors is about 1 mH. You could also check that for your specific motors using an LCR meter if you have access to one.

We have not characterized the moment of inertia for our motors yet, but you can approximate that using the dimensions of the output shaft. The output shaft is made of stainless steel, and its dimensions can be found in the motor’s dimension diagram. That diagram is included in the 20D gearmotor datasheet, and you can also find it separately on the product page under the resources tab.

- Patrick