Re: [CAD_CAM_EDM_DRO] 90v DC motor as servo?

> Yes gear reduction changes the effective inertia forces.
> System performance can be easily calculated with free
> motion control software like that at
>
> http:///www.kolmorgen.com
>
> You need to know the motor inertia, torques, power, etc.
> If you cannot find a spec a fair inertia approximation can be arrived at by
> measuring rotor dimensions and assuming it is a solid cylinder of steel.
> Some of it is air and some is copper but
> it is very roughly a wash. The software will calculate the inertia.

Rotor dimensions might be hard to measure - do PM DC motors have the
same issue with loosing magnetization when dissasembled that steppers
do?

Baldor has inertia figures for their motors on the web. Of course the
one I picked up at a hamfest this weekend was not a baldor, but it was
cheap and should be usefull for something around the shop if it proves
unsatisfactory for this project.

Perhaps I'll compare the case dimensions of mine to the similarly
rated baldor and assume the rotor dimensions are similar if the cases
are.

Chris

--
Christopher C. Stratton, stratton@...
Instrument Maker, Horn Player & Engineer
22 Adrian Street, Somerville, MA 02143
http://www.mdc.net/~stratton
NEW PHONE NUMBER: (617) 628-1062 home, 253-2606 MIT