The Mechanics of Motion Sensing

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."

Comments

Interesting.

[Mendak Jemuna]

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.

Re:Interesting.

[fatphil]

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).

Re:Interesting.

[naoursla]

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.

Other applications

[inKubus]

It would be cool to incorporate this type of controller into a portable device. You could have portable laser-tag like games with real-time mapping, or incorporate some type of ball and it automatically keeps score and records the game. You could have "operations" players indoors that have some different role (view the maps, for instance, and direct the players)

With networking and GIS in a portable device, it's almost necessary to have new interfaces to use all the new space it knows about. In gaming it's the most fun but these types of thing could be used in more professional ways also.

Re:I Thought...

[twistedsymphony]

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).

Who was first?

[Glacial Wanderer]

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.

Re:Very odd

[DerekLyons]

Given the 10+ year development and 20+ year use lifecycles of military equipment it's surprising to see consumer gear _behind_ military tech.

It's hard to actually say who is ahead or behind, partly because tech in the real world isn't a linear scale (like it is in various games), partly because the military deploys such a wide variety of accelerometers. The ones used in, say the Trident-II's MK6 guidance, are certainly much larger than these (about the size of a film can) and are 'old style' (asymmetrical floats in fluid) - they are also much more robust and less sensitive to vibration. (The accelerometers in the MK6 Guidance System are also a neat illustration of the nonlinearity of tech in the real world. It uses an advanced form of the same type used in Polaris - because they are more sensitive and accurate than an advanced form of the (quite advanced in and of themselves) ones used in the MK5 guidance of the Trident-I.)

No fatigue

[exp(pi*sqrt(163))]

I was worried that something like metal fatigue would set in. But metal fatigue is a result of microscopic fractures in the crystalline structure of the metal. These sensors have moving parts that are fabricated from a single flawless crystal. So nothing like metal fatigue can take place.

wii console, remote and sensor bar

[asjk]

The Nintendo Wii Remote one-ups the Sony controller by including an infrared camera. It picks up signals from a sensor bar the owner attaches to the television set. This enables the remote to "know" where it is in relation to the screen, so the player can use the controller to point to things on the screen -- a useful feature in shooting games (and a lot of games are shooting games).

Here's another interesting piece of information. According to this source, the sensor bar is not even communicating with the console! I guess it's just shooting out a reference point for the remote, to act like a virtual mousepad to the remote's mouse?