Re: [CAD_CAM_EDM_DRO] re:Re: suggested improvement for EMC

Ian Wright wrote:

> Hi Jon,
>
> This was really what I had in mind when I said that perhaps the machine
> could back up a bit and 'take a run at the work' after a pause. I hadn't
> really appreciated the extent of the look-ahead but, now looking back over
> earlier posts it seems it can be quite a way so perhaps the idea isn't
> feasible. Is the look-ahead a defined quantity like so many lines

No, the lookahead is infinite, and can extend to the end of the program, if
necessary. In some complex surface contour work, it can actually extend over
thousands or even tens of thousands of blocks of code.

> or, in
> other words, could it be defined in such a way that, if the machine returned
> to a point defined by the beginning of the look-ahead buffer and started
> from there repeating previous 'cut moves' in thin air, it would eventually
> catch up with where it should be in a controlled manner (or would the buffer
> be so large that the time involved in such a move would be impractical)?

It can take 10 - 15 seconds for a 100 MHz Pentium to run through all the moves
in some of my engraving programs, which are the biggest I've run so far.

Jon