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wind27382
02-05-2009, 09:06 AM
Well it's been a long time since I've been on these forumn. I'm not an engineer inf act I'm more of an artist, but I have been trying to create a head tracking unit for a personal project, and I wanted to have you guys advice.

I'm thinking about using a
PhidgetAccelerometer 3-Axis


and of course
InterfaceKit 8/8/8


so far I'm planning on using them to track the rotation of my head movements. I plan on ordering the parts for my simple head tracker today so I really want to get some advice before i spent the money and get the wrong thing. right now my budget is around 200 dollars. it is my goal to build a simple head tracking unit for under 200 hundred dollars. I will also need it to hook directly into my computers usb drive.

darkback2
02-05-2009, 10:17 AM
You may want to use multiple tracking methods. Check out the stuff posted on using a wiimote...If your using a computer anyway you can use a wiimote to track your head position.


http://www.youtube.com/watch?v=Jd3-eiid-Uw

Hope this helps.

DB

wind27382
02-05-2009, 11:50 AM
it helps but i didn't want to use a we remote. I wanted to use my own customize equipment.

besides this is only the first step of the project. I'm originally a 3d artist who wants to be a part of virtual reality. i feel that it will be the future of gaming. here is the steps that I will take

head tracking
first head tracking- simply getting a camera to be able to turn left and right with you head movements.
second finish head tracking- getting the camera to be able to left up and down.
thrid finishing touches- such as extra features such as adding a distance sensor

head mounted display
after I finish the head tracking unit i will begin working on the head mounted display. I know of a company that sells cheap lcd screens small enough to work. while studying at the art institute of pittsburgh I worked for lens crafters as an optical lab technician. i use to manufacture glasse's I'm certified so I know a little thing about vision. so I think that I will be able to make a good head mounted display.

so the first step will be to get tje display actualy mad, and attached to the trackign unit
third step will be to try and get the actual programming working.
and lastly test it to see how I can improve on it.

Adrenalynn
02-05-2009, 12:04 PM
I suspect an Accelerometer is not the way you want to go for head tracking. Building an IR head tracker with a web cam and some LEDs is trivially easy, and is the "pro" way that the higher-end commercial products go.

The advantage to using a Wiimote is that it's a VERY high resolution webcam. Otherwise - it's an identical kinda thing.

http://www.free-track.net/english/

elios
02-05-2009, 05:42 PM
this jonny lee character is very smart. have you guys seen his videos on the active touch screens and white boards?

Adrenalynn
02-05-2009, 05:49 PM
yeah, it's just using the Wiimote's camera and IR diodes on the fingers. It's basically identical to the head tracker. In summary, the camera is seeing the position and orientation of the LEDs and doing the trig to figure out how that maps given parallax in the 3space.

wind27382
02-06-2009, 06:24 AM
yes I get all of that my only problem was that i wanted the person to have 360 degrees of movement. so in other words i want you to be able to turn completely around and look behind you.

Adrenalynn
02-06-2009, 11:09 AM
The problem with using an accelerometer: Once you stop, where's "behind you"?

Their motion is relative.

You would need at least a compass, accelerometer, and gyro to do that well.

darkback2
02-06-2009, 02:49 PM
Are you building a halodeck? :p

The wimote itself uses the IR camera and accelerometer data. You could try puting a compas on a hat or helmet, and coupling that with the camera. That way when the computer looses the IR signal it can switch over to the compass. It may not be 100%, but its better than nothing.

Another idea would be to use roborealm, and have a camera mounted on the persons head. Roborealm could recognize various shapes on cards mounted around the room. The XY coordinates of the shapes would give you your pan tilt, and the shapes themselves would tell you which direction you were looking. Ofcourse you would probably need more than 4 cards because the camera angle would have to be crazy wide in order for that to work...just another though.

wind27382
02-06-2009, 10:10 PM
no halodeck that is just far to above my skill level. i ordered an accelerator so i will be trying to play with it this weekend if it doesn't work i will be trying something else. I will be trying to use two methods to track one to track the axis such as the rotation and another to track the positiong of the head. think of a head mounted display for a virtual reality game if you will.

Adrenalynn
02-07-2009, 12:11 AM
An accelerometer can't track rotation _at all_.

wind27382
02-07-2009, 07:36 AM
actually it looks like I will need an accelerometer and a gyro. the only problem is that I'm having problems finding cheap usb gyros. or one that would work with what I'm planning. but i should have something along the lines of test to post in a few days.