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Re: Ultrasonic Help
Quote:
Originally Posted by apalrd
We have a 10-turn pot sensing drum rotations. The drum rotates slightly more than 10 times, so it is chained (with plastic sprockets) to the drum shaft, providing a slight reduction. We now use about 8 turns of the pot over the entire travel distance.
We don't like encoders for absolute positioning because we don't know exactly where we are, only where we think we should be based on where we assumed (or sensed, with another sensor) we started. The largest issue is that, if we don't start at home, we have to move to home to reset. If we have a practice robot and we don't fold it up into the start position before running it, or we stop running deployed code to change something without folding up into start position, we no longer know exactly where we are. That said, for some mechanisms, it's the best way to do it.
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I share your concerns, and I agree a multiturn pot is probably the right way to go for this.
Matt
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Matt Krass
If I suggest something to try and fix a problem, and you don't understand what I mean, please PM me!
I'm a FIRST relic of sorts, I remember when we used PBASIC and we got CH Flightsticks in the KoP. In my day we didn't have motorized carts, we pushed our robots uphill, both ways! (Houston 2003!)
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