I didn't take any photo but it's quite simple. Just unscrew the motionplus and take out the pcb. Cut of the connector and solder to the extension cable. I use a SDCard holder as the casing and hot glue the cover.

Great idea for a cover!

Used whatever resources we have. This is garage VR. Tested out the headtracker mounted under the HMZ-T1 and it work. At least it look much nicer and less nerdy compare to mounting the motionplus on the head

I would be love to be one of those people, if at all possible. I promise it will get used for interesting stuff!

I finished up the FreePIE code for the iPhone tracker. It's uploaded it to FreePIE so you can download it, but it's not part of the build yet so I have an "unofficial" console-only build and test script if anyone wants to try it out. You will have to purchase the $9 Sensor Data App for your iPhone.
http://itunes.apple.com/us/app/sensor-data/id397619802?mt=8

Then just unzip this package, open a command console, and run "FreePIE.exe iPhone_test_script.lua"


Then under the Sensor Data App, configure the Unicast address to your computer IP, and click "Start Stream".

I was unable to fix or understand the periodic sensor lag problem. Tried shutting down all apps and disabling cellular radio but still no luck. I am curious if other people experience this. (Please let me know) Also, there is a bit of drift in the heading. I think if I calibrated with the magnetic compass, then that would fix it but I am only using the gyro-inertial values right now.

Good luck.

Edit: You will need to have the .NET 4.0 runtime installed and also the Visual Studio 2010 runtime. You can get that runtime here http://www.microsoft.com/download/en/details.aspx?id=5555

Me too, i would love to fix support in FreePIE for it!

@brantlew

Can you characterize the drift? Is it over time, or due to violent motion? I ask because I have an iPod touch, so it only has gyro/acc, and I cannot get it to drift at all, even by violently shaking it for 30 seconds. I'm using the 'iDesktop VR' app to test this, maybe its sensor integration algorithms are superior to those SensorData uses.

Anyway, I'll check out your script tonight and report back.

@FingerFlinger: I actually notice it the most when I slowly rotate the phone 360 or 720 degrees. It seems to accumulate an error - maybe 5-10 degrees after a couple of rotations. As a first approximation, I am only using 1 set of sensor values so there is a really strong possibility that I can correct this error with the integration of more sensor data.

PS. It's possible that its error in my code, but I don't think so. I was careful to avoid coding practices that would lead to floating point accumulation errors.

Hi,

we have already started a Google spreadsheet to classify the cheap trackers out there :

http://www.vrgeeks.org/wiki/device-classification

You are free to modify it

Also :



Actually you have unlimited head rotation, since this is done by the inertial trackers and does not require the blob to be viewed by the camera.



This is definitely not "fixed position", this tracker is real 6DOF. Within a limited range for sure, but all trackers have a limit



Most inertial sensors don't work for translations at all, even if they have accelerometers. So I would place most of them in the first category.
Especially all the so called 9DOF IMUs, which in the end can only give usable 3DOF data..

cheers

@cbwan:


Excellent! I'll take a look at it. I haven't updated this list in a while so it will help me fill in some of the details.


For my purposes, I consider it fixed position if you have to stay within a 3 meter radius (room size). I can see how there is confusion over this classification though. Maybe I should separate into two categories:
fixed = <0.5 meter radius (TrackIR)
limited = <3 meter radius (Hydra, Kinect)


I was careful in my definition to state that they were only able to detect motion. True, you can't reliably double integrate the IMU's to gather positional information. But you can use raw accelerometer and the first integral (velocity) to detect motion. This is often all you need to know. It is sometimes irrelevant to know if you traveled exactly 10 or 20 meters, but it is relevant to know that you started moving at about 1 m/s and then stopped.

Ok




(you also have to be careful to compensate for the acceleration that you detect while rotating, but that's another topic)

I'm not following the forum enough to know what your purposes are,
but I would advise a correct, precise head position.

Small and correct movements of the head are critical for presence because that's how you perceive naturally.
And if you have that, you don't even need to have a stereoscopic display to correctly perceive depth (http://cb.nowan.net/blog/2010/04/28/doe ... 3d-matter/)

We recently tried that at Laval Virtual. Some of the best French VR experts were on our booth and did not realize that we had used the Sony HMZ-T1 in mono.
They felt the 3d was very smooth and not giving any headache.

cheers!

I agree. I almost never use stereoscopic view because it's such a pain to setup and adds little.

LOL! Maybe this was the Synopter effect ( http://www.newscientist.com/article/dn1 ... aches.html )?

No it's not the Synopter effect
There are a lot of cues to perceive depth, stereosopy is only one of them.

Motion parallax is another very important one, and we had a good head tracker so the user could freely translate his head.

http://cb.nowan.net/blog/2010/04/28/doe ... 3d-matter/



The first simulator I worked with had a big monoscopic screen with head tracking, and this worked quite well too.

Yeah, there are a lot of factors other than stereo that help perceive depth. That is a big reason trackers that can provide more than rotational data are so cool.

For some types of simulation, though, there might not be much of a difference. Racing, for example, where your head is not going to be sliding side to side very much.

It wouldnt be of much use in a HMD were the image follow the head, and movies would have to be real time rendered.

It still makes a big difference being able to move your head about, even in flight sims (and I suspect racing ones). When I use a flight sim with only 3DOF, it feels really restrictive and unnatural after using 6DOF sims. Even though I only usually move it a few inches (except when trying to look behind me) it adds a lot to the immersion. Not to mention it also allows you to 'zoom in' on your instrument panel.

When I play Arma I actually disables the zoom feature, it's annoying as hell, and in Arma it does not feel natural, maybe its better in other games

I don't mean 'zoom' as in using the zoom function of the game, I mean the ability to put your virtual face closer to the instruments to seem them more clearly.

Yeah I know, but in arma it feels like you are zooming when you do it

Anybody know anything about these sensors?

http://invensense.com/mems/catalog.html

Nice find. Looks promising, the the prices seem OK.

All SMD as far as I can tell. Not a show stopper, but a pain to work with.

EDIT- cyber, your new avatar is quite disturbing.

Yeah, these will be a real pain to work with if you don't have a hot-air pencil.

The hot air rework stuff isn't horribly expensive, I think the one I got was about £60. Cheap Chinese gear, doesn't actually meet the saftey laws, have heard stories of some potentially deadly wiring errors, works very well, but be careful what you buy.

Hmm, I've only ever used stuff at work, which is pretty nice, generally. Never used hobbyist tier equipment. Maybe I'll have to give it a shot.

Invensense makes great gyroscopes, but it is difficult and relatively expensive for an individual to source their parts. STMicro makes comparable stuff that is much less expensive.

All MEMS motion sensors that I'm aware of are surface mount.

Sorry to junk the thread up. Didnt know where to post this, I found a funny video today of a guy who has a nice setup for skyrim with the TrackIR. What I found interesting was the voice command (footstep sound to walk), if you make it to the end of his video I'm sure you will enjoy his frustration with the setup.

http://www.youtube.com/watch?feature=pl ... vcGqha6xJ0

Set the iPhone up as a tracker the same way brant did and I had the same issue, but not as bad. It would run completely smooth for 20 secs then drop and jerk for about 5 secs. I put the iPhone on plane mode with wifi on so nothing would interrupt and it's still the same. I think it's a limitation of the app. Shame otherwise it runs like a treat.

Fingerflinger, it's not really hobbyist gear, from what I have read the machine I have (Atten Instruments AT858D+) is pretty much the industry standard for low volume work over there. It is just that the safety and quality inspection standards are not the same as what you might expect if you bought it from a shop on home soil.

If you know what to do with such a piece of equipment, it is quite possible you can do the inspection yourself...

Video review.
http://www.eevblog.com/2011/04/25/eevbl ... rk-review/

I will stop being off topic now.

Found a review of the upcoming cinemizer HT; looks promising...
http://the-games-veda.blogspot.de/2012/ ... acker.html

That looks pretty decent actually. Good to know it works without drivers, could be a good choice for a plug-and-play setup.