On Thu, 3 May 2012 12:39:15 +0300, Anders Wallin wrote: >>> The spectrum is so full of noise all the way up and beyond the >>> range >>> of the chart, that it has to be measured on some kind of machine. >>> Jon >> I found the source of this pictures: >> http://www.mmrc.iss.ac.cn/~xgao/papernc/jounce20111122.pdf >> And I am not sure what was measured. From this motion >> profile (0.1 to 0.2 s time to reach max. velocity) >> I do not expect frequency components in the >> 800 to 1200 Hz range. >> Another point is that the spectrum does not look alike sinc. >> But I may be totally wrong. > > The authors of that paper are not very clear on what exactly was > measured, but I am sure it is not just an fft of the > velocity-profile. > Rather is a vibration measurement from somewhere on the machine. As > such it might have components from the spindle, servo-drive, etc. > > If someone really wanted to get into this on a hobby level there > might > be acceleration-sensors (made for e.g. airbag-triggers on cars) which > could be used? > Simply HAL-scoping commanded/actual position and maybe looking at > their spectra might be a good start too.
Actually a high end smart phone with the new fancy nano gyros + accelerometers might just do the trick. ------------------------------------------------------------------------------ Live Security Virtual Conference Exclusive live event will cover all the ways today's security and threat landscape has changed and how IT managers can respond. Discussions will include endpoint security, mobile security and the latest in malware threats. http://www.accelacomm.com/jaw/sfrnl04242012/114/50122263/ _______________________________________________ Emc-developers mailing list Emc-developers@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-developers
