Hello, I've been revisiting this velocity estimation thing again, and was wondering if anyone is actually using the velocity estimate output from an encoder. I seem to recall there was a variant of PID called PID2, but can't find it in the codebase. Does anyone use this or remember the details?
My concern is that the PWM-driven voltage mode servo amps I use sound awfully "grainy" at low speeds, and it is clear that quantization of the encoder counts (both in position and time) leads the regular PID to see huge artificial jumps in perceived velocity. Turning up the D parameter magnifies this effect, as would be expected. Something that would smooth out these excursions in apparent velocity from one servo period to the next seems like it would be a big help. I'm working on copying the velocity estimation from the encoder.c hal component, but I was wondering what to do with it after I have the velocity pin outputting a clean, non-quantized velocity. Thanks, Jon ------------------------------------------------------------------------------ Download new Adobe(R) Flash(R) Builder(TM) 4 The new Adobe(R) Flex(R) 4 and Flash(R) Builder(TM) 4 (formerly Flex(R) Builder(TM)) enable the development of rich applications that run across multiple browsers and platforms. Download your free trials today! http://p.sf.net/sfu/adobe-dev2dev _______________________________________________ Emc-developers mailing list Emc-developers@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-developers
