Re: Re: Is this a silly idea

On Thursday 11 December 2003 7:11 pm, CAD_CAM_EDM_DRO@yahoogroups.com
wrote:

> Message: 15
> Date: 11 Dec 2003 01:05:41 -0600
> From: Tony Hursh <awh@...>
> Subject: Re: Is this a silly idea
>
> On Wed, 2003-12-10 at 06:04, Jon Elson <elson@...> wrote:
> > No, you should be able to write a simple kinematics routine for
> > EMC, and use the rest as is. The only thing you have to worry
> > about is the "gimbal lock" problem. If you ever drive the machine
> > through the 0 - 0 point, the results are unpredictable at the center
> > of rotation of the rotary axis.
>
> Computer graphics guys avoid the gimbal lock problem by using
> quaternions rather than Euler transformations. A quick Google shows
> that the International Space Station is using quaternions also (movie
> fans may recall the "gimbal lock" incident in Apollo 13).
>
> Maybe quaternions could be applied here?

Tony Hursh

Thanks for bringing this up. In fact, Till Franitza suggested that EMC
ought to think about these several years ago. If I remember right it
went right over most of the heads. I know it did mine. But then I'm
just one of the EMC loud mouths with very little programming skills and
even less understanding of the logic of it all.

Ray