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I was getting very erratic readings from a rotation sensor (if I put a pendulum on it and moved it back and forth the 0 position would wander all over the place). I started looking at the raw values from the sensor and comparing them with what the (...) (25 years ago, 25-Jan-00, to lugnet.robotics.rcx.legos)
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| | Re: rotation sensor mystery solved?
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(...) When I wrote my original post I was afraid that major surgery was going to be required to fix this. The values with an extension wire are actually shifted into formerly invalid slots which are contiguous with the existing state groups. So the (...) (25 years ago, 25-Jan-00, to lugnet.robotics.rcx.legos)
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| | Re: rotation sensor mystery solved?
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(...) Will this version also work with fresh batteries and short cable, or do we have to change tables depending on the battery state ? (25 years ago, 25-Jan-00, to lugnet.robotics.rcx.legos)
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| | Re: rotation sensor mystery solved?
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(...) old (...) The version I posted works with all cable lengths and battery strengths I have access to. I just extended the range of each state a bit toward the low battery end of the scale. --Ben (25 years ago, 26-Jan-00, to lugnet.robotics.rcx.legos)
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| | Re: rotation sensor mystery solved?
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I put in some debug code to catch rotations which skip a state (transitions like 3->1 or 0->2) which the legOS table `diff2change' currently translates to 0 steps (because we can't be sure whether that was 2 steps forward or 2 steps back). These (...) (25 years ago, 26-Jan-00, to lugnet.robotics.rcx.legos)
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| | Re: rotation sensor mystery solved?
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(...) Hi Ben, i think that's very interesting work you're doing, especially because i'd like to build sophisticated balancing bots, and already got 2 rotation sensors from lego world shop for this reason. I'm currently not actively working on that, (...) (25 years ago, 26-Jan-00, to lugnet.robotics.rcx.legos)
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| | Re: rotation sensor mystery solved?
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(...) It is very very interesting. I have worked the last weeks evenings to discover the fault in my concept, my modell and my Software. and I have discovered, that the fault can't be on my side. I discovered that my implementation of a fake (...) (25 years ago, 26-Jan-00, to lugnet.robotics.rcx.legos)
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| | Re: rotation sensor mystery solved?
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(...) I tried hacking something like this into the old rotation sensor code, and it didn't go real smoothly, but is definitely a necessity (I think) if you want the sensor to handle very, very high speed apps. (...) I am. I'm almost tempted to steal (...) (25 years ago, 26-Jan-00, to lugnet.robotics.rcx.legos)
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| | Re: rotation sensor mystery solved?
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(...) What exactly do you intend here, Martin? I spent quite some time working on this over the summer and in the fall, and had a great deal of problems but also some success. I'd be happy to help you out with my experiences if you have some idea (...) (25 years ago, 26-Jan-00, to lugnet.robotics.rcx.legos)
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| | Re: rotation sensor mystery solved?
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(...) I got a letter two days ago indicating that the two rotation sensors I ordered the first week in January are nicely on backorder and will ship in a month or so. This is similar to what I was told on the phone when I ordered them from Shop and (...) (25 years ago, 26-Jan-00, to lugnet.robotics.rcx.legos)
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| | Re: rotation sensor mystery solved?
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(...) which (...) I added code to assume that 2 step transitions were 2 steps in the last known direction of travel. The results were MUCH worse than just ignoring those steps, as the current code does. This seems to suggest that the 2-step (...) (25 years ago, 26-Jan-00, to lugnet.robotics.rcx.legos)
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| | Re: rotation sensor mystery solved?
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(...) That's one of the reasons I got mine. I was trying to make a simple balancer when I built the pendulum I described (with 4.5 degree accuracy). There were a lot of problems with my mechanism, but the overriding problem was that the 0 point (...) (25 years ago, 26-Jan-00, to lugnet.robotics.rcx.legos)
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