Re: [CAD_CAM_EDM_DRO] cheap high speed servo control

Graham Stabler wrote:

> I am currently designing a coil winding machine for small hot air bonded
> bobbinless coils, one thing I would like is a servo motor as the spindle
> to allow good speed control as well as angular control at the start of
> winding. i.e. I want to be able to drive it quickly (up to 3000rpm) and
> then use it more like a stepper motor during wire attachment etc.
>
> The gecko drive units look good but would I be correct in assuming that
> the servo could not be run at speeds as high as 3000rpm? The max step
> rate is 250khz so I suppose it depends on the encoder.

Right. 250 KHz is actually a LOT! 3000 RPM is only 50 rev/sec, so a
1000 cycle/rev encoder x 4 quadrature counts/cycle x 50 R/S = 200,000
count/sec.

> Are there any other fairly cheap drivers that might allow me to drive
> the motor both at high speed and in step mode? I will probably run the
> machine from a microprocessor which will be given winding constants (no.
> of turns etc) via a pc link.

Yes, there are several. Apparently Rutex also has a similar device.

Jon