 | | Any experience with measuring rotations?
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Hi all, I am working on a "project" where I want to measure some reasonably small rotations, things on the order of +/- 10 degrees or less. Just to make it hard, the force acting on the thing being rotated is small, like, completely hypothetically, (...) (18 years ago, 20-Jan-07, to lugnet.robotics.nxt)
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| | Re: Any experience with measuring rotations?
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(...) Easy. A light sensor. Point the sensor at a disk that's shaded from white to black. I've used that to detect the distance a robot is from a wall (wall following), using just a black & a white dot (1x1) which are moved in front of the sensor. (...) (18 years ago, 20-Jan-07, to lugnet.robotics.nxt)
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| | Re: Any experience with measuring rotations?
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(...) "It's foolproof!" (...) This sounds like a good idea. I'm thinking I'm going to have to work out a sequence of more than just two shades, but that's what weekends are for, right? So, if I could make of sequence of colors that have increasing (...) (18 years ago, 20-Jan-07, to lugnet.robotics.nxt)
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| | Re: Any experience with measuring rotations?
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(...) Don't mess with colors. Just use a gradient. You'll have a mostly linear set of values. With my black & white studs, there are also several shades of gray in between (like a little black & mostly white...) (...) no. :) Steve (18 years ago, 20-Jan-07, to lugnet.robotics.nxt)
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| | Re: Any experience with measuring rotations?
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(...) I am not rally an NXT guru, but seems the best way would be to simply measure the distance and calculate the angle. Tommy Armstrong (18 years ago, 20-Jan-07, to lugnet.robotics.nxt)
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| | Re: Any experience with measuring rotations?
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(...) I am not really an NXT guru, but seems the best way would be to simply measure the distance and calculate the angle. Tommy Armstrong (18 years ago, 20-Jan-07, to lugnet.robotics.nxt)
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| | Re: Any experience with measuring rotations?
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(...) In the document (URL) find a paper-disk with grey gradient. The document was part of my presentation at the 2005 Annual Robolab Conference in Austin/TX. There was a second part (URL) don't remember, if those documents ever have been available (...) (18 years ago, 20-Jan-07, to lugnet.robotics.nxt)
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| | Re: Any experience with measuring rotations?
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(...) Well... there's two things here, and Steve solution actually addresses them both. Do you actually need a continual series of states, and the "weight" of the thing on the end of the beam, or just know if something *is* on the end of the beam? (...) (18 years ago, 20-Jan-07, to lugnet.robotics.nxt)
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| | Re: Any experience with measuring rotations?
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(...) I made a sequence of stacked 1x2 plates, running from black to red, through green dark grey, light grey, tan, white, yellow, and orange on the way there. My nxt gave me reflected light values running from about 12 to about 52. The nine steps (...) (18 years ago, 20-Jan-07, to lugnet.robotics.nxt)
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| | Re: Any experience with measuring rotations?
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(...) Hi Tommy, This is a good idea; I'll try the ultrasonic sensor to see what it can do. Thanks! (18 years ago, 21-Jan-07, to lugnet.robotics.nxt)
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| | Re: Any experience with measuring rotations?
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(...) Thanks for the technical details, Claude. It's going to take me some time to get through this! Rafe (18 years ago, 21-Jan-07, to lugnet.robotics.nxt)
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| | Re: Any experience with measuring rotations?
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(...) What I need to do compute the average position of a number of items across the length of the teeter-totter (!). If, on average, they are in the middle, then there is no rotation and I should get zero. If there are more on the left than the (...) (18 years ago, 21-Jan-07, to lugnet.robotics.nxt)
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| | Re: Any experience with measuring rotations?
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(...) Well put quite simply... The probability of some event A occurring given that event B has occurred is equal to the probability of event B occurring given that event A has occurred, multiplied by the probability of event A occurring and divided (...) (18 years ago, 21-Jan-07, to lugnet.robotics.nxt, FTX)
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