On 2014-11-20 19:25, andy pugh wrote: > On 20 November 2014 14:29, Marius Liebenberg <mar...@mastercut.co.za> wrote: >> Andy why were you disappointed with the position feedback. >> Will it be ok on a slow moving bed? >> Do you think a more powerful MCU will do the trick? > It was noisy and dithered a lot. The Arduino has to measure 2 voltages > per measurement. To do it fast enough it had to be only 8 bits and the > shortest sample time that the Arduino could handle. Even then the > carrier was only 1kHz, whereas Resolvers normally work at at least > 5kHz. > > So, two noisy values divided by each other = a very noisy result, > which gives a noisy arctan and a lot of servo dither. > > Yes, a more powerful MCU would be better, and it so happens that Mesa > and Pico sell exactly that all ready to go. > > Why will nobody believe me when I say that my experiment was rubbish? Nobody will believe that of an esteemed gentlemen like you. I only need one channel so the mcu route seems ok but I might replace the resolver with an encoder and a reference location switch.
-- Regards /Groete Marius D. Liebenberg +27 82 698 3251 +27 12 743 6064 QQ 1767394877 ------------------------------------------------------------------------------ Download BIRT iHub F-Type - The Free Enterprise-Grade BIRT Server from Actuate! Instantly Supercharge Your Business Reports and Dashboards with Interactivity, Sharing, Native Excel Exports, App Integration & more Get technology previously reserved for billion-dollar corporations, FREE http://pubads.g.doubleclick.net/gampad/clk?id=157005751&iu=/4140/ostg.clktrk _______________________________________________ Emc-users mailing list Emc-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-users
