[req]free-track Head Tracking

[android78]

I was wondering if anyone here had tried this:
http://www.free-track.net/english/
If so, please post any comments here.

There are many videos on youtube using it and it seems quite good, even though there's a bit of lag.

If you've managed to get it working, please let me know how it is. How do you find it in relation to other solutions, such as the VR920 compas/accelerometers?
Also, is there a way to maybe use something similar to this for a controller? If you were to set it up and have red and blue leds, red for head and blue for controller, would this work? I may have to look at the source code and see what I can make of it.

[nubie]

This looks awesome, I want to try it, maybe I can soon. All sorts of projects are getting in the way, like paying jobs though, and of course NAW.

Ever tried a SpaceOrb? I found one at the local second-hand shop, and then I bought a Playstation ORB to replace its ball with a new one (after I had practically repaired the original by cutting it open and gluing it back together with SuperGlue).

Then I found a shop selling the PSX versions for $1 apiece, so I grabbed 4 ($20 with shipping.)

I think that the ultimate solution should involve 6-DOF for the head/view, and 6DOF for the vehicle/movement. (I know of no game able to make use of this but the Descent series, and even then only for the ship, not the view.)

[android78]

I'm not quite sure what you mean about 6DOF for the vehicle. One game that appears to have implemented a different head movement to gun is Armed Assult. Have a look at this youtube video where the guy is looking round and running the one direction:
http://www.youtube.com/watch?v=p_bm9dLOVss
I had a look at the game and I'm not sure how they set it up for this. Maybe it's a hack to the game code to allow the view to be different.

Just an update:
I managed to remove the IR filter from my old webcam (broke it into bits to get it out so there goes using it for a normal webcam... big loss) and affixed a visible light filter (floppy disk magnetic disk) to it. Pointing a remote control at it seems to work well. I can control the mouse on screen reasonably well.
I can't comment on how good the 6DOF is since trying to hold a button down on 3 remotes and hold them in a triangular formation is rather hard... I'll try to get a simple IR led chain rigged up soon and see if I can get it to work.

[crim3]

I had a look at the game and I'm not sure how they set it up for this. Maybe it's a hack to the game code to allow the view to be different.

By default, in armed assault the head can be moved with the keypad numbers (snap views, this is from operation flashpoint) or with trackir. Look at the controls configuration, though it's not very intuitive to configure.

[nubie]

I'm not quite sure what you mean about 6DOF for the vehicle.

I mean exactly what I say (have you ever played Descent?), the vehicle can move in all 6 axis freely, and your head can move independently.

The problem with these games is that no matter how capable the setup, all anyone wants to do is walk/drive around like real life, instead it can be used to try things that aren't possible or very hard to do in real life. With a 6DOF movement you can do neat things with a 6DOF vehicle, I know of no vehicle in contact with the ground that uses 6 degrees for movement.

So kill the IR filter and use the software, OK. I should have a drawer full of old TV remotes (or just the fronts of their PCB's I broke off for just such an occasion )

Just an edit, I got the IR filter removed, I put one layer of floppy material in it as a filter, but I don't think it is enough, I think I will attach some more externally.

Mine was a bitch to get apart, I ruined the threads all down the side, and cracked the lens, it cracked around the actual lens part, so I guess it is OK. I guess I will attach the LEDs to my Polarized glasses, that way I can take them off quickly.

[nubie]

How many mA would you put through a standard IR LED? I am getting 106mA from my dual setup (admittedly after they got a little hot and I added a 10 Ohm resistor. Luckily I think they were pretty dead NiMH AAA, so not much harm done.)

I may have a wirelss IR emitter for some headphones, that thing got quite hot in operation, but I can pull a lot of LEDs from that, and possibly get them to a reasonable output level without so much amperage.

[sharky]

20ma is usual

[nubie]

That is what I figured, so I put another 10 Ohm resistor in series.

I dug up another TV remote for the Third LED, just need to get it wired.

[sharky]

at how many volts are those leds rated?

[nubie]

They came from a TV remote, I am not sure now if it was a 2 or 4 cell remote.

I am using 2 AAA NiMH batteries, so they should provide ~2.4-2.6v With 20 Ohms resistance and parallel wired it seems to pick up just fine.

[sharky]

i found some infors about IR leds.. since they are in a remote i assume they are normal, not high power.

U=1.3V
I=0.01mA

R=U/I

U=2.6-1,3=1,3
R=1,3/0,01=130 Ohm

you should place 130 OHM resistor in series if your informations are correct. this is calculated for 1 led...

if youre using 3 leds parallel then the calculation should be this:

U=2,6-1,3=1,3
R=1,3/0,03=43 Ohm.

this is the drawing:

Code: Select all

+2,6 ----[43 OHM]-------------------
                     !      !      !
                     !      !      !
                     !      !      !
                     !      !      !
                     !      !      !
                     !      !      !
                     O      O      O
                     !      !      !
                     !      !      !
                     !      !      !
                     !      !      !
                     !      !      !
- 0 --------------------------------

this is correct only if you have standard ir leds.

[nubie]

Wowsa, that would explain the high draw I was seeing.

I suppose I could always use a single battery, that will greatly help if I put the battery head-mounted.

[sharky]

yep you can use a single battery too, but you allways must have a resistor in series.. 5 ohm or so should be ok..

[nubie]

I used a 10 ohm resistor and 2 batteries for 3 LEDs, I would guess that they would be high output for a remote, you want the TV to get the signal.

It is amazing, it really really works. now I need a game to use it with. And a mount for the webcam.

[nubie]

I put it on a headset I got from the second-hand shop, I just played a little Live For Speed Alpha Y, native support, it is very nice. I have it off to the side of me because of the planar setup, so it is a bit off.

All you need to do is get it working in the FreeTrack window and fire up Live For Speed, as soon as you get in-car you will know it is working. No settings or anything.

I am going to try the Planar setup with LFS now, first impression is that you lose the sense of what the car is doing (with no G force feedback from the car you can't tell what it wants to do except for the view, and now that is gone too.)

Edit: Just tried it, amazing. It really transports you there. The funny thing is that you really want to look around, but the instant you do, off the road, just like real life. I was playing with the mouse and that probably made it worse. It might be easier with the wheel, but I don't want to have to set that up too.

[sharky]

hahahhaah i hgave made it! 4 led version!what i noticed is that it uses a LOT of resources.. ingame with a dualcore quadro i really notice the difference...but its great anyway! does somebody have an idea on how to assign a prog to antoher cpu?

[sharky]

cheap 'n easy.. i used blue leds and a cellphone charger.. works very well

[android78]

Nice one Sharky.
Are you running the LEDs in parallel? I thought that unwise since they are diodes and they may not be matched. This means that you may have one with a low voltage that will be much brighter then the rest.
I like the idea of hotmelt glue on masking tape!

[Likay]

He has a currentlimiting resistor at the top of the cap. hehe. Nice one Sharky.

cheers

[sharky]

thanks guys!

even if they burn out its not a problem.. i ordered 1000 leds of various kind for 200$ 1 year ago and have MANY still..

[LukePC1]

Nice project. I remember there was a thread like this, but noone made the trouble to build LED's in it - so it worked quite bad.

The program used there was Cam2Pen with
NoLimits Simulator Demo.
I think the two should work quite good together.

I built myself a helmet (for cycling) with LED's. I think I'll try them with these headtracking software - and hope, they are stronger than the sun shining from the window

PS: I just ordered 100 white LED's for about 20€ a couple of weeks ago.

PPS: I tried cam2pan with flashligt version, but I don't get the right results. My camera is either to slow or there is to much different light, that anoyes it.

PPPS: I tested the free headtrackin thing and it didn't turn out that bad. At least it didn't interrupt so ofthen as the cam2pan thing (which shuts down after 5 minutes).

@ sharky: How does the 4 point cap perform? My webcam does only 10fps, so I see some lags, but using only 1 point results in some wrong values.
Can it manipulate the mouse? I could only test it with live for speed, which is supported with profile. I think if it's worth to build a 4 point cap...

[sharky]

hi! 4 point performs wuite well IF you set up the correct led distances. else it fails and makes wrong movements. if it lags you should lower the webcam resolution!

in my case i had to make the room dark to avoid interferences.

i need to try no limits coaster.. lol has to be lot of fun!

[Dyssident]

I am completely blown away by this program. I had no idea something like this existed (for free).

To quickly test it out tonight, I plugged in one of my dusty old webcams and used my TV remote as an LED point and it works with just that! (for 2DoF/Single Point of course). Amazing. I haven't decided what specific setup to go with yet, but I'll definitely be putting something together with this.

As a budget gamer, this solution and my $4 shutterglasses make me very happy

[sharky]

i reccomend you the 4 led solution! it is much more accurate and gives you much more head directions for just 10 cent more..

[Xeno]

For those who want to spend more but keep it simple (i.e. do not want to fiddle around with resistors and LEDs):

I bought a bike helmet backlight from a hardware store for 6 Euros. It has 4 red LEDs, battery inside and fits almost perfect to my basecap. You only have to shorten the flashing circuit by soldering a switch to it. From what I learned from other forums, there seems to be no great difference in accuracy between using normal and IR LEDs.

I'm not quite sure what you mean about 6DOF for the vehicle. .

6DOF lets you not only turn, but also lean/shift your position in a vehicle. Works very well with an unofficial mod in IL-2 1946 (in fact the game that made me buy that defective VR920 on ebay... ).

http://www.youtube.com/watch?v=_2EOnt6yyPY

[LukePC1]

Why do you want to shorten the flashing circuit?
Is it a faster 'blinking' or flashing that is needed?
I tried with normal LEDs in white and the sun from the window was eqally bright - if not birghter...

so what did you do?

[android78]

Why do you want to shorten the flashing circuit?

I think he means short out the flashing circuit... so it is always on and not flashing at all.

[Xeno]

I think he means short out the flashing circuit... so it is always on and not flashing at all.

Exactly, that's what I meant - sorry for my english!

[LukePC1]

Yeah... but you get a lot of 'wrong' lighting then, don't you? Or do you have a completly dark room?
Maybe it was also my webcam... very old, very slow, very bad quality

[android78]

Yeah... but you get a lot of 'wrong' lighting then, don't you? Or do you have a completly dark room?
Maybe it was also my webcam... very old, very slow, very bad quality

I tried it with some white LEDs and the results were terrible. Tried making the room as dark as I could and still wasn't enough since the LEDs don't seem to emit enough infra red for the filter to work, and without the filter there is too much other light. Maybe in a totally dark room it would be OK though. One other thought is that maybe RED LEDs would work ok... not tested this though.
I tried with IR LEDs and it seems much better. I need a better webcam though since mine is about 10 years old and at 640*480 only does about 10FPS!

[Xeno]

Yeah... but you get a lot of 'wrong' lighting then, don't you? Or do you have a completly dark room?
Maybe it was also my webcam... very old, very slow, very bad quality

I use a Creative LiveCam IM (cost ~ 25 Euros) and the red LEDs that were fitted to the helmet light. Works in daylight. At night, I have to turn off the light, because I have a Lamp behind my head and to make things worse, a mirror behind the lamp, causing false signals.

Have you already tried lowering the threshold in Freetrack's setup?

[LukePC1]

I was just fidling around some month back... And it was terrible - and my location is not the quietest or darkest, so I don't expect much of trying again - and thus are too lazy for it.

I'm not even shure, how good the webcam can detect IR light...

I was able to use it short for Live for Speed Alpha (I hope that's the name) and that rolercoaster Demo, which is linked somewhere here... If it worked good, it would be good for that games, but it was still a lot of fun and costed me 0€

[Xeno]

Hmm. Some webcams work better with a piece of film in front of the lens or somthing like that. Not sure about this but I remember reading it somewhere in the freetrack forum. Didn't see great difference. It may also help to flatten the LEDs with a file and sand them a little. The rough surface gives a more uniform light intensity. Oh, and you can reduce reolution to 320*240. That should reduce the lag. I had pretty good results with my system. Only some kind of lock-up, when my head turns left too quickly. But according to the developer, that's a software error, because a certain value turns negative.

[DragonM]

I'm surprised nobody has pasted these links yet:

http://www.cs.cmu.edu/~johnny/projects/wii/
http://www.youtube.com/watch?v=Jd3-eiid-Uw

(The second one is also embedded in the first, as an inline Youtube video.)

It's a web page and video by Johnny Chung Lee of CMU about how to use a Wiimote as the camera for head tracking. (Scroll down to the bottom for the headtracking project.) While TrackIR rigs are $150, a Wiimote is $40, with performance just as good. See Johnny's page for technical details of what a Wiimote can do. Add your own infrared LEDs and that's all the hardware you need. Of course, if you own a Wii, you've got the Wiimote already and only need the LEDs. This method does NOT require any changes at all to the Wiimote, so you can use it with your PC for a while, then take it back to your Wii at any time and it will continue working fine.

I see in this thread that Freetrack will support Wiimotes, so it seems Johnny's work has been noticed.

DM

[crim3]

The wiimote's IR cam is perfect for free-track. The image processing is all done in the wiimote itself and only the position and size of the dots (up to 4 dots) are transmitted to the host, freeing the computer from all that processing time that makes free-track a burden right now. It's more expensive than a webcam but not very expensive by itself. Maybe the wiimote's support by free-track will boost the sales of spare wiimotes.