Re: [CAD_CAM_EDM_DRO] Re: Re: Re: Polar Coordinates CNC?

At 10:35 AM 11/5/02 -0600, you wrote:

>If we select a quadrature encoder or used a stepper motor with
>gearing/belting sufficient to get that resolution, do you think that the
>greater accuracy as we approach the center would still cause problems?

Of course not. But don't you then use up more CPU time calculating? IE,
either you compute all the arcs regardless of size or you compute fewer
arcs depending on the smaller radii on some parts, which latter involves an
additional function. But anyway, the error on polar machine is always going
to be greater at extremes of the machine, whereas with Cartesian machine it
isn't

Much the same applies to hexapods. The error is between two and five times
the actuator error, compared to the one times actuator error of Cartesian
machine.

Regards, Hoyt McKagen

To prevent virus propogation, don't put this addy in your book
Belfab CNC - http://www.freeyellow.com/members/belfab/belfab.html
US Best MC - http://www.freeyellow.com/members/batwings/best.html
Camping/Caving - http://www.freeyellow.com/members/batwings/caving.html
Two-Wheel-Tech List - http://batwings.freeyellow.com/2whfaq.html
Never trust a fat man