sorry for what maybe sounds like a dumb question, but having read the Proctor/Shackleford paper on the influence of jitter on steppers which basically say: "all it causes is a loss of torque on the order of 10%" (given the figures at the time the paper was written),
also, having never seen a stepper stall myself except when banging into a limit: Am 06.12.2012 um 20:47 schrieb Gene Heskett: > On Thursday 06 December 2012 14:38:54 Michael Haberler did opine: > >> Gene, >> >> just curious on your method: >> >> Am 06.12.2012 um 17:14 schrieb Gene Heskett: >>> Chuckle.. NP Kent, but I would point out that it only takes one >>> out-lier of an extra 50 u-s, in a 25 u-s loop, to cause a stepper >>> stall and a wrecked part or tool. To me I could care less if its 2 >>> u-s or 7 u-s because they aren't show stoppers. But that 2x a day 50 >>> u-s lag IS a show stopper because that is the puppy that will >>> cheerfully eat your lunch. >> >> How did you determine a) the stepper stalled (for how many steps?) and >> b) actually the cause was the delay you mention? >> >> - Michael >> > If a stepper stalls, running above 1/3 its max speed, and does it at random > times, that is the doorstep I lay the blame on. Do you have any hard evidence for that, or is that pure conjecture? How do you discriminate that suggested cause against mechanical overload? - Michael > How many steps before I > can hit the estop is immaterial because if it slips one step, it is stopped > forever since it cannot re-accelerate to running speed in one step once the > late step has passed, at least until linuxcnc slows down to reverse or turn > a corner, at which point the motor may well picked and run again. But > since linuxcnc is unaware of that, the point is moot, either the work, the > tool, or both are probably damaged beyond repair. > > Cheers, Gene > -- > "There are four boxes to be used in defense of liberty: > soap, ballot, jury, and ammo. Please use in that order." > -Ed Howdershelt (Author) > My web page: <http://coyoteden.dyndns-free.com:85/gene> is up! > It is your destiny. > -- Darth Vader > I was taught to respect my elders, but its getting > harder and harder to find any... > > ------------------------------------------------------------------------------ > LogMeIn Rescue: Anywhere, Anytime Remote support for IT. Free Trial > Remotely access PCs and mobile devices and provide instant support > Improve your efficiency, and focus on delivering more value-add services > Discover what IT Professionals Know. Rescue delivers > http://p.sf.net/sfu/logmein_12329d2d > _______________________________________________ > Emc-developers mailing list > [email protected] > https://lists.sourceforge.net/lists/listinfo/emc-developers ------------------------------------------------------------------------------ LogMeIn Rescue: Anywhere, Anytime Remote support for IT. Free Trial Remotely access PCs and mobile devices and provide instant support Improve your efficiency, and focus on delivering more value-add services Discover what IT Professionals Know. Rescue delivers http://p.sf.net/sfu/logmein_12329d2d _______________________________________________ Emc-developers mailing list [email protected] https://lists.sourceforge.net/lists/listinfo/emc-developers
