A few of us duscussed this at Fest and before. You can use a stepper motor and just vary the current in one coil as the force feedback. I don't think you can reliably use the other coil as an encoder, but it could be possible. We saw an Allen Bradley MPG that appeared to do exactly that though - a stepper motor with some analog circuitry to do pulse shaping. (I don't know if it did force feedback - it may have used both coils for quadrature)
As for load, you should be able to get a rough approximation from the PWM output value (from PID). High output means high instantaneous load. You may want some filtering on that, but it should work OK. - Steve Kirk Wallace wrote: >Has anyone done a jog wheel with force feed-back for detents and/or axis >load? It would be nice to have a jog wheel or quill lever to do "manual" >drilling or cutting. Do any of the current commercial CNC's have this? > >Jon, is there any test point to get a load signal from your PWM amps? > ------------------------------------------------------------------------- This SF.Net email is sponsored by the Moblin Your Move Developer's challenge Build the coolest Linux based applications with Moblin SDK & win great prizes Grand prize is a trip for two to an Open Source event anywhere in the world http://moblin-contest.org/redirect.php?banner_id=100&url=/ _______________________________________________ Emc-users mailing list [email protected] https://lists.sourceforge.net/lists/listinfo/emc-users
