It's simply a method whereby position increments are added to the PID command in a time sliced (1KHz in my case) fashion (v=dp/dt).
To achieve an axis velocity of 1m/s, the PID command is incremented by 1mm at 1ms intervals. From there the PID does it's thing which might involve wagging a bit (dithering) from one update to the next to maintain that velocity.
If "v" isn't dithered then the servo loop won't add any of it's own. Mostly, you'll just get oscillations at a lower frequency. If you want a dithered DAC then it'll need to be applied directly to the final demand.
Normally the PID function scales it's demand output to suit the DAC but there's no reason not to target a larger word size then dither that down to the DAC. I guess in that respect, this then becomes an added feature of the servo loop.
I do not know if you ever scoped the switching behavior of a power fet. If not, do it and your focus will change. Otherwise: try to interpret the measurin g carefully ;-)
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If "v" isn't dithered then the servo loop won't add any of it's own. Mostly, you'll just get oscillations at a lower frequency. If you want a dithered DAC then it'll need to be applied directly to the final demand.
Normally the PID function scales it's demand output to suit the DAC but there's no reason not to target a larger word size then dither that down to the DAC. I guess in that respect, this then becomes an added feature of the servo loop.
The MOSFET gate voltage certainly looks amusing. It's a bit of a wow moment watching it the first time.