I don't think that would work well. Think about the situation where you have several (mostly straight) short line segments, the last being the shortest, and then a 90deg turn. I think many would find it unacceptable to overshoot the last segment 10thou if you were doing something like inside corners.
I only have two machines running linuxcnc so far (both commercial gantry routers, both steppers) as a hobby so have limited experience but I don't think the look ahead is that big of an issue *IF* the machine has decent acceleration capability & is properly tuned to use it. I can process complex 3d profiling in wood on the big one right about the limit of my spindle hp (~100ipm w/ a 1/2" ballmill). Yes, it probably does limit me slightly when doing a final finishing pass w/ a smaller bit. When Im doing aluminum sheet at ~30ipm its a total non-issue though. I have a factory CNC 3hp Wells Index knee mill w/ DC servos that Im retrofitting (slowly.) If LinuxCNC can keep up on the gantrys it will be no problem FOR ME on the knee mill. But I see how it might be a limiting factor for a modern Hass class speed machine w/ massive spindle hp and feed rates possible when profiling. But those would typ have very high acceleration levels to match. Machines w/ very low acceleration levels will suffer the most as they won't be allowed to get up to speed if you can't slow them down very fast. Its like what they say about driving at night: "Dont outdrive your headlights" :) More segments of look ahead would no doubt be an improvement. But how much? (seriously, I think we'd all like to know.) Can people give examples of machines and jobs where cutting speed is a problem due to limited look ahead? I don't have enough experience to even be able to guess the magnitude of the issue. Best, Stephen I think that if this is actually the case it would make more sense to > set a lower limit on this distance (INI file setting?) so that the > motion system would guarantee stopping in the next program line or > (for example) 0.01" > > ------------------------------------------------------------------------------ For Developers, A Lot Can Happen In A Second. Boundary is the first to Know...and Tell You. Monitor Your Applications in Ultra-Fine Resolution. Try it FREE! http://p.sf.net/sfu/Boundary-d2dvs2 _______________________________________________ Emc-users mailing list Emc-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-users
