Since everything is in motion, how will this interact with the PID or other timing loops? I wonder if that would be sufficient to filter out the vibration.
On Aug 10 2015 1:04 AM, Julian Wingert wrote: > A median filter shall be a good start here > > On 10. August 2015 08:40:02 MESZ, Nicholas Mc Guire > <der.h...@hofr.at> wrote: >>On Sat, 08 Aug 2015, Peter C. Wallace wrote: >> >>> > >>> > I think the trick the Resolute encoder uses is this: the image is >>captured in >>> > a perhaps sub microsecond flash of the LED, and then the "image" >>can be >>> > shifted out of the sensor at a leisurely rate. The specifications >>sort of >>> > suggests this (very fast capture (ns) time, but only multi KHz >>maximum update >>> > rate) >>> > >>> > Peter Wallace >>> > Mesa Electronics >>> > >>> >>> They may in fact use a laser for illumination as AFAIK you can get >>higher peak >>> power with a pulsed laser than a LED. These are in the $30 region >>> for >>75W peak >>> 40 ns pulse width, not much vibration or motion blur in 40 ns :-) >>> >> >>the problem is not the vibration in the 40ns >>but that the recorded encoder image is more or less >>a random position within the vibration range of >>the device + vibration of the laser - I was thinking >>about compensations like done with satelite images >>where multiple pictures are taken and then the signals >>are compensated by filtering out szintilation effects >> >>If the actual sampling is in the multi kHz range only then >>that would be well in the modes that such systems can have >>and one - worst case - would have the full vibration in >>the positional information. Just wonder if there are any >>detection algorithms that look into such issues. Naively >>one could do a fft on the position data under the assumption >>that motion should be constant/known-trajectory and that >>could reveale such vibration/aliasing induced errors. >> >>> >>http://www.osram-os.com/osram_os/en/products/product-catalog/laser-diodes/high-power-laser-diodes/pulsed-laser-diodes/hybrid-pulsed-laser-diodes/index.jsp >>> >>> ( thank you Harold Edgerton ) >>> >>thx! >>hofrat >> >>------------------------------------------------------------------------------ >>_______________________________________________ >>Emc-developers mailing list >>Emc-developers@lists.sourceforge.net >>https://lists.sourceforge.net/lists/listinfo/emc-developers ------------------------------------------------------------------------------ _______________________________________________ Emc-developers mailing list Emc-developers@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-developers
