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How the Wiimote Works
The New York Times' 'How it Works' series touches on a remote with a twist: the Nintendo Wiimote. The article describes the micron-sized machines that make it work, displays cut-away graphics of the little white marvel, and rounds out the discussion with a breakdown of where the tech came from. From the article: "The controller's most-talked-about feature is the capacity to track its own relative motion. This enables players to do things like steer a car by twisting the remote in the air or moving a game character by tilting the remote down or up. 'This represents a fabulous example of the consumerization of MEMS,' the tiny devices known as micro-electro-mechanical systems, said Benedetto Vigna, general manager of the MEMS unit at STMicroelectronics, a leading maker of the accelerometers embedded in the controllers. (Nintendo itself declined to talk about the controllers' inner workings.) He said the motion sensors, using the technology that activates vehicle air bags, can accurately sense three axes of acceleration: up and down, left to right, and forward and backward."
C'mon, "editors"...this is SlashDot, not Time. Most people here could probably have written that article blindfolded. How about a couple of real tech articles today?
This just in.
Nintendo is using their wiimote technology to determine when the wiimote flies from the users hand, and will now deploy an airbag before striking your HDTV.
Please return your wiimote for the new version with the wiirbag.
The sixaxis must be twice as good! Either that or Sony failed geometry...
I heard that the lifespan of a MEMS accelerometer is usually on the range of 10^15 oscillations, which disappoints me GREATLY.
I thought the Wiimote worked like this:
If you see a monster, throw the Wiimote directly at the monster. Depending on your aim, the monster will die in a shower of bright sparks and crackly noises, or the monster will hurl various objects back at you such as books, chunks of plaster, ceiling fan blades, or your little brother's eyeball.
[
independent researchers have shown that there is a strong link between very high voltages coming from the accelerometers and the state of inebriation (and perhaps low IQ) of the player...
"A door is what a dog is perpetually on the wrong side of" - Ogden Nash
So did they actually use tools to open the Wiimote up carefully? Or did they fling it with all their strength at an HDTV to get both an article, and piece of the class-action?
Slashdot Burying Stories About Slashdot Media Owned
After having used my Wii and the controller for a couple weeks now I've been somewhat disappointed with the technology.
First, the Wiimote isn't an absolute pointing device. It's all relative to the Wiimote bar you place near your TV. Everything is relative to that device, so you are never actually pointing accurately at anything on your screen.
Second, the Wiimote has accuracy/responsiveness issues. Not sure if it is interference from bright lights or some other type of wireless/electronic devices. There are times where you are having to repeat the same motions over again because the Wiimote isn't registering.
Nothing fatal, but the hype certainly has worn off. Hopefully Nintendo will be coming out with updates to make the Wiimote more consistent in registering input over the next year.
This article sounds a lot like this slashdot story of a few weeks ago entitled "The Mechanics of Motion Sensing"...
..to the Wiimote - at least reversed from the eeprom on the device. This should improve the compatibility of PC's to the Wiimote, and I hope we see some interesting applications on the PC soon ; that or Nintendo should release a Wii-SDK, otherwise I think they are definitely losing a whole lot of interest in the long run of the more adventurous type of user who longs for interesting applications for this simple (proven) but now widely available concept of three-axis sensing devices.
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Someone should tell Sony that thier controllers are also moving through time. Maybe they'll release a clock upgrade to make it an EightAxis.
I'm a bit confused. The ability of the Wiimote to sense the angle it's at seems quite consistent, and doesn't appear to be possible to "fool", while the ability to sense motion can be fooled somewhat.
It seems to me that they must be separate, at least a little. You can walk away with a Wiimote, far out of bluetooth range, turn it however you like, bring it back... And the console will still sense its orientation precisely. Location? Games that use that sometimes get out of sync so you have to wave the Wiimote around a bit to get them better calibrated.
So I'm pretty sure that's a separate feature, to say nothing of the additional component of the CCD pointing at the IR sources above your TV to give you a pointing device.
My blog: http://www.seebs.net/log/ --- My iPhone/iPad app: http://www.seebs.net/seebsfrac/
In my last post, I missed that the vectors were hidden because I used the tag containers.
The first should be [0,0,-9.8] and the second should be [15,15,15].
Apology to Ubuntu forum.
While I love the Wiimote and Nunchuk, I think they really suffer from the lack of at least a single-axis gyroscope. The accelerometer is great for measuring tilts in relation to the earth's surface, but they can't register angles on axes perpendicular to the earth's surface. This makes it more difficult to register a camera pan to the left or right, for instance, without involving the IR sensor.
The most obvious use (to me) for such a feature would be to have the Nunchuk pan the camera left and right as you point it left and right (in FPS games for instance), but it would also improve situations like batting and swordfighting where you want the instrument onscreen to match the angle of the Wiimote as closely as possible.
That's true, but that's not what he was talking about. (Well, he was, but not in the part you quoted.) He was talking about how the place where you're really pointing is not the same as where it thinks you're pointing, and you can verify this yourself.
If you stand close to the TV -- not so close that it goes haywire, but close -- you'll see that it thinks it's pointing way off, depending on how you point, and usually in the vertical direction it's the most severe. And unlike the sibling poster said, this has nothing to do with its sensitivity. It has to do with the fact that the ONLY information you are allowed to give it about the sensor bar (in Wii options) is whether it's above or below the screen. WHAT???? It doesn't allow you to give it ANY more information about the real boundaries of your screen, which would allow the OS to have some trivial transformation to make it line up perfectly.
To be sure, this isn't a problem for a lot of applications. For one, as long as you are allowed to see where it THINKS you're pointing, and it's not miles off, it's perfectly functional. Also, for more than about ~8 feet away, the error is very small. But if they want to have a game like, I don't know, Time Crisis or House of the Dead, where you're not supposed to have the luxury of knowing where you're really pointing until you fire, it falls short.
A game could calibrate this, but I only know one that does -- Zelda -- and that's only horizontal, not vertical, which is the bigger problem.
BEFORE YOU MOD TROLL, let me just say that I love playing the Wii, but it bothers me to no end that they didn't put in a very trivial step that would vastly increase functionaly. Sure, I can understand them not *forcing* you to calibrate like that on startup, but to not even bury it under some advanced options?
Apology to Ubuntu forum.
This is fucking hilarious. I will proceed to let you know precisely how most vehicle air bags are activated.
It is true that in the more modern vehicles there is ONE accelerometer per direction of air bag. This is used to set off air bags other than the front. There is usually one accelerometer to set off the front air bag.
HOWEVER this is not the only input. In fact it takes two inputs to set off the air bag. One input is that accelerometer sensor. The other input is either crash sensor mounted in or near the front bumper.
This is the hilarious part - these sensors typically consist of a magnet, a ball bearing, a ramp, and a set of contacts with another magnet. A sufficient shock will break the ball bearing free of the magnet, at which point it rolls up the ramp (again, if the shock is enough) and sticks to the other magnet, closing the switch contacts.
So what this guy is saying is that the technology in the Wiimote utilizes is a combination of an accelerometer and a ball bearing rolling up a ramp.
Seatbelt? High-tech shit! --Carlin
"You're right," Fisheye says. "I should have set it on 'whip' or 'chop.'"
If you see a monster, throw the Wiimote directly at the monster. Depending on your aim, the monster will die in a shower of bright sparks and crackly noises, or the monster will hurl various objects back at you such as books, chunks of plaster, ceiling fan blades, or your little brother's eyeball.
--
I always use a +2 Wiimote for my games.
-- Tigger warning: This post may contain tiggers! --
I'd M2 that unfair.
Time is very dumbed down, and uses slang my middle school English teacher wouldn't allow. That's for non-technical articles.
The NY Times article doesn't tell us anything we didn't already know.
Apology to Ubuntu forum.
So I need to ask, if I turn on the nightshot in my sony camcorder, am I going to screw up people playing with their wii?
(Nightshot emits an IR beam)
Could I make an IR device to screw up my friends with just an IR LED?
but you could define three orthornormal axes for the accelerometer and three orthornomal axes for the gyroscope, which would be ... wait for it... sixaxis. We do this all the time in the aerospace world because you don't always mount the accelerometer and the gyroscope in the same manner. Each set of axes can be defined by a 3D vector and related by a 3x3 matrix.
But try this: hold the Wiimote up to your eye, and look along the Wiimote like using the sight on a handgun. In actual fact, it lines up perfectly, at least for me. It just doesn't feel like it does. I'm not sure why.
Well, duh. The Remote can't know where you place your TV, or how big your TV is. That's why there is a sensor bar. Games are free to calibrate your remote, though, so that the "TV offset" is corrected. So far, none do this. You could fix this by creating your own wider or smaller sensor bar - I thought about creating a small white sensor bar I can place inside my projector's picture.
The responsiveness issues seem to depend on the games. Some have a pretty big lag, some don't. It never bothers me during gaming, though, I only notice it when I'm moving the hand.
Lastly, I think you're confusing the accelerometer and the "pointing mechanism." The fact that the Wii sometimes doesn't register your motions has got nothing to do with bright lights or interference. It's simply you not making the correct motions. Motion sensing does not depend on the sensor bar.
I'm totally happy with my Wii. I'm playing it at least one or two hours every day, since I got it on Europe launch day. I have friends over every second day, and five of them have already bought or ordered their own Wiis (and the number would be higher if more Wiis were available). I pronounce the Wii "best console ever."
Nope, there is just the accelerometer and the sensorbar, no other sensor in the Wiimote. That the sensorbar can detect tilt in one axis is simply the result of having two (or more) IR dots. available, tilt detection in racing games works via the accelerometer, the tilt info from the sensorbar might be used for those funny pointer rotations.
Actually it (the sensor bar) is most likely used to correct drift. In the VR industry this would be called a six degree of freedom hybrid inertial tracker. The primary method of detecting the pose of the controller (position + orientation) is by integrating the results from the accelerometer(s) over time. The problem is that since we're integrating digital values, we don't get this nice discrete integral, so we get a lot of error. Now this doesn't matter when you don't need an absolute position and/or orientation (like for steering/swinging a tennis racket/etc), and on the bright side accelerometers have a very quick response rate so you get good interaction with them. By adding an additional source of orientation data (in this case the IR lights on the sensor bar) we can correct the errors in the integrated pose when we need accuracy. Other systems often use things like ultrasonic clicks for calibration to avoid line of sight problems... But since the idea is to point at the TV when you're wanting to do precision aiming, you don't really have to worry about line of sight.
Maxim: People cannot follow directions.
Increases in truth directly with the length of time spent explaining them
Clearly those with modpoints do not know how airbags are set off. I fucked the curve all up in my Automotive Electronics class, and surely know more about it than the idiots who modded me.
"You're right," Fisheye says. "I should have set it on 'whip' or 'chop.'"