Re: Relating Stepper Motor Current To Torque

From: Bryan Hackney (bh.remove_at_bhconsult.com)
Date: 12/28/03 

Date: Sun, 28 Dec 2003 18:26:57 GMT

Ted Wood wrote:
> I'm looking to measure the torque generated by a stepper motor by
> relating it to winding current during steps. Has anyone done anything
> like this or can anyone suggest some references?
>

[...]

How were you going to measure torque? I have an idea to build a small
dynomometer - one of those projects that will probably never happen.
I have the equipment, but putting it together is a challenge.

This involves using a good brushless DC servomotor and digital drive.
The drive needs to be able to operate in a torque mode and provide output -
probably in the form of an analog out or streaming data that corresponds
to the various drive parameters - speed, torque, etc.

Hook the motor to be studied up directly to the torque drive. Create
estimates of the viscous and dynamic drag of the servomotor. Adjust the
torque of the servo to observe the curves of the motor under study.

Relevant Pages

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