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The Mechanics of Motion Sensing

Posted by ryuzaki0 on from the ride-that-dragon dept.

Dr. Eggman writes, "The AP has a short technology piece on the mechanics that go into the motion-sensing capabilities of the Wii and PS3 controllers. It also details some of the past uses of the technology and gives a nice overview of just how far the technology has come from the earliest missile-guidance sensor equipment."

10 of 119 comments (clear)

  1. Interesting. by Mendak+Jemuna · · Score: 4, Interesting

    Interesting, but I have one question. Do the silicon springs recalibrate every so often, or will they wear out and break? My old N64 controller did this.

    1. Re:Interesting. by drinkypoo · · Score: 5, Informative

      They're so minute and move so little you will never have to worry about them breaking. Because they are so tiny you can never build up appreciable inertia in them. They are functionally considered solid state devices and they should last pretty much forever.

      --
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    2. Re:Interesting. by fatphil · · Score: 5, Interesting

      Should - and do. One of Freescale Semiconductor's clients' more popular uses for accelerometers is in industrial applications -- BIG kit -- on things that vibrate constantly. Things that vibrate more and more as bearings dry or wear (hence the need for the accelerometer - so you can perform detect this and perform maintenance before your printing press, or whatever, self-destructs). The accelerometers outlive any of the parts they are supposed to look after.

      Freescale has some pretty cool electonmicrographs of their 2-axis and 3-axis accelerometers - www.freescale.com, sensors, accelerometers, and browse around - I can't actually find the images now. I have a PPT on my work laptop, but that's no use. Grab a ZSTAR for <$50, and simply have a play with one yourself - (that includes everything - hardware and development kit).

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      Also FatPhil on SoylentNews, id 863
    3. Re:Interesting. by naoursla · · Score: 4, Interesting

      I asked a MEMS researched about this once. He said it comes down to fatigue. If you bend a paperclip back and forth a bunch of times the metal fatigues and eventually breaks. Fatigue occurs because the metal actually migrates around the bend. MEMS components are so small and move so quickly that they do not rest in one position long enough for fatigue to occur. The same principle hold for the springs in accellerometers and the mirrors in DMD projectors.

  2. Re:I Thought... by twistedsymphony · · Score: 4, Interesting

    In all seriousness I believe Nintendo would actually allow it. They really haven't blocked non-family content since the ESRB has been around and people have been able to get a better idea of the game content before they buy it through it's rating. Also have you seen the number of dating sims available for the DS that deal with "touching" not just in Japan but in the US too.

    The biggest roadblock to "adult" Wii entertainment isn't Nintendo but retailers, your EBGames, BestBuys, and Walmarts refuse to carry any "AO" rated titles meaning if a company did release them they'd get very limited to almost non-existent exposure... in the US at least (most of the rest of the world is a bit less prudish).

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  3. MEMS by Mike1024 · · Score: 5, Informative

    A good picture of a two-axis accelerometer can be seen here: http://users.wpi.edu/~cfurlong/me-593Mech.html (second picture down). Sensing is usually performed by capacitive combs, structures which act as capacitors, with their capacitance varying with displacement.

    MEMS accelerometers have dropped in price in recent years because there's a big market: the automotive sector. A typical new car needs two accelerometers, one for the traction control system measuring roughly plus-or-minus 2 to 4g, and one for airbag deployment measuring more like 50g.

    Two big manufacturers are Analog Devices and ST Microelectronics, though others exist.

    The high demand of the automotive sector has driven prices right down; sensors which would have cost hundreds of dollars in the past can now be purchased in bulk for less than $4. In fact, you could order one right now; component retailers will sell you one for less than $15.

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  4. Re:no gadget required to detect the direction of by heinousjay · · Score: 4, Funny

    One of these days, your doctor will figure out the dosage and your posting will cease. Truly a sad day for all.

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    Slashdot - where whining about luck is the new way to make the world you want.
  5. Who was first? by Glacial+Wanderer · · Score: 5, Interesting

    The Nintendo Wii Remote one-ups the Sony controller by including an infrared camera.

    I think they meant to say: The Sony controller dumbed down the Wii Remote by excluding the infrared camera.

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    Hobby Robotics
  6. Re:camera problems by anotherone · · Score: 4, Informative

    It has accelerometers AND the sensor thing. Tennis actually just uses the accelerometers, it works quite well no matter where you're facing.

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  7. Re:Question for Slashdot by JCondon · · Score: 4, Informative

    Tilt sensors indirectly measure orientation (tilt). They look at the change in the gravitational acceleration vector with respect to the sensor coordinate frame.