FreeTrack Forum

Yeah so - I got this program last night (been looking into trying this kind of thing for a while now) and had the idea this morning that this kind of implementation could further expand its usefulness.

http://www.youtube.com/watch?v=YpQxhe-FtKo

That's an extremely basic concept video, but I'm sure you get the idea.

As for why you'd want to do that - it's because it would give a more natural feeling of looking around. The monitor would have a fairly wide plane of movement available to the user, and would still support full 6DOF.

The green ball on the right side of the displayed video represents the webcam, which instead of being placed infront of the user, would be placed behind them, with the controls in the program reversed.

Obviously, this kind of setup would require a bit of extra programming for the relevant outputs to the device. The hardware etc would also obviously need to be constructed, and a controller made for it. Then, naturally, space would be required for the user to put it on their desk.

Not for everyone, of course, but I reckon it could be a useful application for people that enjoy their racing sims. (with a strong enough mounting system, a 3 monitor 'surround' implementation could also be done - altho, by this time, the price involved is getting near simply buying a monoscopic VR headset with a really nice resolution)

*edit* Please disregard the tilt/rotation on the monitor; this is an issue with the animation portion of the software that I was too lazy to fix.

The vertical track would simply move left and right on the horizontal track, and the monitor would move up and down on the vertical track.

*edit #2* thread title changed to better reflect what the thread is about

That would be hard to make. Heavy, noisy and probably too slow. And there's already a easier way of doing that. You buy one of those head-mounting monitors, usualy refered as "video glasses" wich can produce the illusion of a 40" screen at 2m distance. You attach the 3 leds on it and bingo. With correct settings it would imerse you in a virtual world. Their problem was the low resolution (800x600) but there's already some (expensive) HD models (1280x720) on the market. And they even support stereo 3D. Imagine that... one HD video glasses + stereo 3D + Free-track... cry.

Construction difficulty should be fairly low; you're using part of a radial inverted cog for the rails - these can be obtained or made at places specializing in medium to heavy duty cog based tracks.

Electrical motors would be used to move it along the tracks with fairly good accuracy and speed - naturally, the heavier the monitor, the stronger the motor needs to be. Think of the robotics used in assembly lines, as seen here:

http://www.youtube.com/watch?v=uV_m59v_LJM&feature=related

Balancing would be one of the only other issues; it would need to be shaped such that the monitor has the correct amount of radial rotation so as to always be directly facing the user, without the rails wrapping too aggressively (so as not to impede the movement of the monitor itself)


My dad was a mechanic and helped with aeronautical engineering projects on occasion, and sometimes came home with a small scale industrial robot to help with stuff he would work on at home; the machines themselves were not loud by any stretch - only the operations they performed could get noisy. In most cases these were powered by a diesel generator, tho, and that was very much noisy...


As for the head mounted displays; I consider this to be an alternative solution that would work out cheaper, provide the user with the functionality of a normal (and adjustable) desktop environment to use when not using the head tracking, and still be capable of 3D display (see stereoscopic LCD shutter glasses and products such as the zalman 3D LCD displays).

This would also afford users the ability to use hi resolution displays, rather than lower resolution HMDs, such as 1280x720p models, which tend to start from around $650 for a mono display, and upwards of $1k for a stereoscopic one.

They are also prone to compatibility issues, as well as flawed stereo display in many games. They are also not suited to all users, as some do not have sufficient eye-relief adjustability.

Depending on the strength and scale of construction, this device could also be used to mount large format displays such as 42" LCD TVs with 1080p resolutions. With the advances in display technology we're seeing lately, the weight and depth of LCD TVs are also decreasing, making them lighter and easier to use in a system like this. Bendable LCD displayes are also becoming more of a reality, with products such as the Alienware super wide display may soon become commercially available.


The only reason I am not making this device myself is because I lack the programming knowledge to write the hook-outs that would be required in the free-track software to use it with the device, the programming knowledge required to program the controller for the device and the funds to actually purchase the hardware and components required to build the device.

For the cost of making something like this work, you might be better off buying some additional monitors, or perhaps even projectors for a cave-like immersion experience.

Joe Dunfee

Projectors are another consideration, but do again have their own set of issues. A projector with a nice resolution, say 1280x1024/1280x960/1280x720 can easily set one back over $850 USD - I'd estimate construction of this device would range somewhere around $500 USD, leaving you with $350 in comparison to spend on a nice LCD monitor to use on it.

Buying additional monitors would also work, yes - however, for the up-down, you'd need a second set of monitors above your line of monitors - and if you're centering yourself between them, you have the bezel issue where your crosshair is divided on the horizontal plane; so you'd in effect need a surround setup of 9 monitors for the best 'spread', for compatibility.

Beyond that being expensive in its own, it would also be an issue to run, as you would require hefty hardware, would again need to be playing a game that supports it on a driver/hardware interface level and something such as the TripleHead2Go device to make it an effective 'three' monitors being used, not nine.


Now. With a projector, it should be noted, a similar device to this is entirely possible, altho obviously also more expensive. A means could be found to mount a whitescreen for the projector to disply on infront of the user, with a motorized rollcage that the projector rests in, also driven by the same device. This would naturally provide a much larger potential screen area, albeit with ambient lighting issues and with a much larger area to use it in being required. Depending on the extent of implementation, however, further implementation of the 6DOF idea could also work.

All of that does, again, however, place the cost in the same region as a stereo HMD at $1,500 or more, with a 1280x720 resolution; comparable to what you would end up paying for a projector using system anyway.


As I said, I envision this as an alternative affording the user the ability to use their monitor(s) as they normally would; to even remove them from the device and put them on their normal stands if they want to move the monitors around, say to a friend's place. The device would probably range somewhere in the region of 20kg to 40kg, depending on materials used for construction.

I'll work on a more robust 3D model of the device to explain the operational principle and to give an estimate of the costs required to produce it.

Any mechanical solution will cause the "lag problem". Try to move a head fast to check your left-6, then right-6. Rapid fast movements, you know... On the other hand if it would be limited to max. 30-45 degrees of a real movement, well - it might be useful. In that case the main feature would be a much smaller eyes movement when "looking back"...

Anyway - virtual glasses is the best solution IMHO, but the expensive one as well...

I don't think you really need 9 monitors.  6 might be a sufficient spread.  A lot depends on what you are trying to simulate.

As for projection. Another benefit of projection is that you don't have to move the projector itself.  You only need to move a mirror to redirect the image.  So, a projector situated above a viewer can be projected onto surfaces around them and the image moved very quickly.  But, then, such a surface would need to be spherical, and normal optics are not designed to focus on a sphere.  One of the laser projectors would work since they have no focusing needs... but those are quite expensive.

perhaps the projector can be aimed at a flat screen that is moved, rather than moving a monitor.  The rotational inertia would be dramatically reduced.

Joe Dunfee

Well, let me chime in:
While I like the idea in principle, it's not all that good.
First and foremost, EVEN if you discount mechanical lag, space and money issues, you will have to move your head in pretty broad sweeps to get the 'most band out of your buck' - otherwise what's the point? And it will get pretty tiring soon enough... unless you are in a desperate need of a neck workout, heh.

As for perfect virtual reality - I think that ultimate (except for direct mind-machine interface a-la Matrix, of course) would be attaching a color laser projectors in the goggles, and have them draw the picture EXACTLY on your retina.
Once it will hit 9000x9000 resolution, it might as well be Matrix, minus all the inconvinience of having a socket grafted into your head :).

OP, I like this concept a lot... this is the kind of things I think of too.  However just like Balor I must say that the idea is not that good... I would say it's actually a pretty bad idea... good innovating, just not in the way you would accomplish it.

Maybe you'd just be best off with something that is a stationary screen that wraps around you kind of like a small version of the Soaring Over California ride at Disney California Adventures... I've never been there myself but my girlfriend has told me that pneumatic seats lift off the ground and you can't see any edges of the screen from where they position you.

Then you wouldn't have to have the mechanical lag associated with an X-Y track and rails or drive-screw type system because you could have the "screen" moved around by a small mirror right at the exit of the projector reflecting your image into the spot you're looking at.  This mirror could be shaped in such a way to correct for the curved screen you're projecting on.

cadcoke4 has the right idea... and really a mirror to accomplish this would be SUPER cheap as compared to your idea of moving the actual monitor.

Think something like a room-sized egg-ish shaped object with a projector and chair inside.  You could find a pre-made mirror and shape your dome accordingly to save money.

Also, I have experience with building something along the lines of what you're talking about (a servo controlled x-y robot) and it's NOT cheap... Think 5-10 times more money than what you currently are estimating if you want even REMOTELY good tracking, movement speed, weight capacity, and noise level.

lol at you for thinking anything even a quarter the size and speed of that robotic arm in your second post would cost anything less than 5000 if not 50000.

The more I think about it the more I realize how unnecessary your type of "moving window" into the game world really would be.  Because all you're REALLY trying to accomplish is a reduction in how much you have to turn your eyes to still face the monitor which is totally pointless because you can just up the sensitivity of your head tracking... or get a bigger monitor...

How about you just get a large concave surface, say maybe 10 or 15 feet in diameter, and you paint it with that special paint for making surfaces into projector screens (yes they make it).  You stand it up so that it's vertical, and then sit yourself in a chair 2 or 3 feet back from it with your eye level as the center of the bowl so you're basically "inside" it and would have to actually be looking over your shoulder to see past your screen.  Then you just get yourself a convex mirror and bounce your projector image off of it on it's way to the screen in order to compensate for the concave shape of the screen you're sitting in.  Nothing would move, it'd just be a big-ass screen that you can't see past the edges of.

Now on the subject of the goggle-type screens... I don't think they should be included in this kind of idea.  Not because they are expensive (OP's idea would cost FAR more than he estimates), but because they are attached to your head... it's annoying...

Hi

I did it

http://www.youtube.com/watch?v=bOEj-F9LPTM

https://www.youtube.com/watch?v=qbX9j5bWz5k

This is quite awesome! Question though: how heavy is such a projector...? :P

Heavy

Should be used with a pico projector!