Comments on: Cheap 360 degree head tracking

By: oscar cutino

oscar cutino — Fri, 15 Feb 2008 03:45:54 +0000

hi , i need information about haw i can hack the xbox 360 hardware .

By: Andrew Watt

Andrew Watt — Tue, 12 Feb 2008 01:50:47 +0000

Um, I’m trying to picture why 360 is necessary. My head certainly can’t do that.

Game design for owls?

By: Joel Clemens

Joel Clemens — Mon, 11 Feb 2008 19:51:30 +0000

hi guys, I'm the one who sumbitted the news for this article.
a couple things need to be addressed
1. i know it is similar to Johnny Lee's wiimote VR projects, i too started with the wiimote, but since the wiimote doesn't have a GYROSCOPE it cannot track 360degrees of rotation, with with its IR tracking.

2. the accelerometers are used to know which way is up (because of gravity) therefore GlovePIE can provide an angle of Pitch and Roll, which i applied into the game. Yaw (rotation) is calculated with the gyroscope and is easily calibrated if you understand how to program in glovepie.

3. the HMD that i used it technically off the shelf, the casing is from an old VFX1 VR helm that was gutted and retrofitted with a (very) cheap evertek HMD

i'll be making another video soon, and i'll post it my website eventually.
-joel

By: Forrest Voight

Forrest Voight — Sun, 10 Feb 2008 23:15:54 +0000

To compensate for drift in gyroscopes like this, you can use a Kalman filter to fuse data from accelerometers and gyros. The accelerometers can find the direction down to compensate for drift.

By: tom61

tom61 — Sun, 10 Feb 2008 22:53:21 +0000

Cool. Very tempting now that you can get these controllers for ~$30 online now.

I wonder if just having the nunchuk (which has another accelerometer) connected to a wiimote if you could get enough data to do the same thing. You’d get wireless working right now this way, though it’d cost more if you didn’t already have the Wiimote/nunchuk (which I’m guessing a fair number of people do).

By: Andrew

Andrew — Sun, 10 Feb 2008 19:05:10 +0000

edz,

It’s not absolute rotational sensing in the horizontal place, it’s just acceleration around the axis (at least, that’s my assumption). So, given that these accelerometers tend to accumulate error over time, there will eventually be drift. But, for the purposes of VR, you probably wouldn’t notice it until you took the googles off and noticed you were standing in a different direction than when you started (although, it would be really weird if the tilt of your head started to drift such that you had to physically tilt your head in order to make the image appear level).

By: EdZ

EdZ — Sun, 10 Feb 2008 18:34:13 +0000

Waitaminute, it has absolute rotational sensing in the horizontal plane?! How is that even possible!

By: Andrew

Andrew — Sun, 10 Feb 2008 17:53:14 +0000

Woa, the sixaxis as an accelerometer with 6-degrees of freedom?? That’s freaking awesome! Kits for those accelerometers were over $100 on sparkfun last time I checked. With the Wiimote, you need to combine information from the the sensor bar to derive position while the remote is moving in order to get more than 3-degrees of freedom. I hope people can get the sixaxis’s bluetooth communication figured out – I think at the moment people who do this need to use the wired usb connection.

By: n3rrd

n3rrd — Sun, 10 Feb 2008 17:24:39 +0000

This is very similar to the Wiimote version, posted here:
http://www.hackaday.com/2007/12/21/wiimote-head-tracking-desktop-vr-display/

This one is demonstrated with already existing programs, though. The Wii one is demonstrated for a type of software that doesn't really exist until now.

By: biz

biz — Sun, 10 Feb 2008 14:40:16 +0000

badass