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Z800's head tracker and magnets

Posted: Thu Mar 06, 2008 1:37 am
by crim3
It seems that I have ruined the head tracker of my z800. I was testing how magnets affect the head tracker. I placed a strong magnet near it and since then the earth magnetism sensor gives erratic data.

So, if you have a z800, don't place magnets near it!

I can't use it now :'( and I'm missing it deeply.
I've tried to contact eMagin by e-mail to ask for head tracker replacement (Nec-Tokin MDP-A3U9S as far as I know). As any z800 user knows, all I got is silence from them. I tried to contact nec-tokin directly yesterday, but no answer by now.

If anyone knows how/where to get a new mdp-a3u9s and how much it could cost (I'm willing to pay anything, or almost anything, to restore my life back to normality) I'd be very grateful.

Posted: Thu Mar 06, 2008 1:46 am
by Welder
Owch!

I thought it was bad to stick magnets at any electrical component though.

Posted: Thu Mar 06, 2008 1:51 am
by crim3
I'm already aware of the foolishness of my action. Don't pour salt on the wound. :'(

Posted: Thu Mar 06, 2008 1:54 am
by Welder
But it cleans it out!

Nah it's understandable, I've broken several things while experimenting.. but usually that includes a soldering iron, a 9 volt battery, and a small electric motor that is only supposed to run off of a double A.. and a small 4 inch tall toy BattleBot from K-Mart. but annnyway...

Posted: Thu Mar 06, 2008 1:59 pm
by 3DGUY
I think you have maybe magnetised the sensor, it makes me wonder if it would naturaly fix itself if the magnetic field weakens over time. Sorry to hear that happened though.

Posted: Sun Mar 09, 2008 1:48 pm
by sharky
ouch.. that hurts...

Posted: Mon Mar 10, 2008 1:48 am
by crim3
This weekend I've been trying to use the raw 'gyros' values of the motion sensor directly. They give a measure of the angular velocity in each axis. It's relatively easy to calculate the angles from these velocities. In fact, they work quiet well, and got excited at first. But... man, everything goes "out of axis" in a few head movements! That's why this motion sensor includes accelerometers and a compass, too. Inertial tracking is not accurate enough to be practical without some kind of absolute reference.

Now I know how much **magic** is behind the final yaw, pitch and roll values that the driver gives, with everything done: angles from angular velocities and correction over time using the compass and the accelerometers. Those guys at Nec Tokin are good, very good!!.

To sum up things, it seems that at the end I will have to spend several hundred euros just 'cos I'm retarded and build a new wall at the computer room as I opened a hole hitting it with my forehead :)
But first... I'll try to work a bit with the wiimote's IR cam, my last hope hehehe
I'll have to decorate my z800 with some IR LED's.

Posted: Mon Mar 10, 2008 2:09 am
by sharky
http://www.nec-tokin.com/english/product/dl_sensor.html you could try to write them.. you could ask for a "demo" component.. :D usually they sell them but they cost a little bit more (5/10% more since you order only one)

good luck

Posted: Sun Apr 20, 2008 1:20 pm
by crim3
'Everything is "connected"' XD
The other day, when I read the reply about how the CRT works, I search for information at the wikipedia, and read a description of how the demagnetization of the CRT 'grid' works (they use a coil that generates a variable magnetic field). Well, since then, I've been thinking of what I have at home that have a coil and can produce that kind of variable magnetic field. Finally, today, I used a soldering gun ( http://www.kelong-co.com/eopen.asp?product=282 ) which has a really big coil on it that doesn't care about any FCC rules or whatever :)
I have dedicated some magnetic baths to the motion sensor, and is working again as always, that is, as bad as always XD
Aaaaah, this feeling..... I think they call it love XD my little z800 :*** luv u so much

Posted: Sun Apr 20, 2008 2:44 pm
by sharky
engineous! congrats.. :D

Posted: Mon Oct 13, 2008 4:31 pm
by phil
That's a heart-warming story :D

Since we're in the 'off-topic' section:
Once when I was little, and my parents were out, I tried putting a big speaker magnet against the screen of our (CRT) TV, and it left huge green and purple marks. I was expecting a pretty loud telling-off when they'd return to find their TV ruined. Then I got the idea that I could turn the same magnet round the other way and put it back on the same part of the screen. It worked - totally healed the marks as if nothing had happened 8) So I turned my attention to the cookie jar.

I think the moral of the story is "believe in yourself".

Posted: Mon Oct 13, 2008 4:31 pm
by phil
No, wait, it's DON'T PUT BIG MAGNETS NEAR STUFF :lol: