Quote:
Originally Posted by Ether
I think what Joe was saying is that the encoder is inherently a position transducer and the Jag would have to differentiate the signal to get rate... and at low speeds the signal from the encoder is not changing at 1000Hz so you can't get a 1000Hz rate signal from it.
[edit] I guess I was reading between the lines too much [/edit]
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There is that problem as well. But No, I had totally missed the velocity feedback mode.
As to counts frequency, at 256 counts per output of say a CIMpleBox and a 3:1 to an 8" wheel (1ft per rev) youll get 32 counts per inch (256*3/24). At this resolution you fall below 1000hz update at roughly 2.5fps. BUT... the code may use edges instead of periods to estimate speed (4X) if it does then we'd be pretty close the range where we cover all useful FIRST robot speeds (.6 fps seems slow enough for me)
Even without this, a slower update rate may be fine as long as we don't go crazy with the D gain.
We'll have to try it and see.
Joe J.