Digit Geek

Oculus Thrift

Since the moment you even heard of the Oculus Rift, you know you’ve wanted it. The price is, of course, a major turn-off unless you’re rolling in money or recently suffered a windfall. Don’t despair however, for we have a solution. All you need is that Rs 500 that you’ve stashed under the bed, an Android phone, a webcam and a few assorted odds and ends and you’ve got exactly what you need to build that most awesome of gaming peripherals by your lonesome.

Here’s a list of what you’ll need:
1. Android Phone (rooted) with a 4” screen at the minimum.
2. A webcam (ideally one that supports 60Hz recording) that you wouldn’t mind ripping apart if necessary.
3. An old floppy disk or a strip of developed film (that old Kodak roll that your dad used to put in his camera)
4. Some old sheets of cardboard.
5. A pair of scissors.
6. A pair of magnifying glasses (or aspheric lenses to be more precise) with lenses that measure about 1.5” in diameter: Rs 160.
7. Three LEDs (Infra-red, 1.4V, 100mA if you want to be more precise): Rs 60
8. Glue / Fevicol / Tape
9. Strips of conductive wire (at least 6 segments of wire, each being 6” in length)

Recommended items:
1. Glue gun, because it’s better at gluing stuff.
2. Wire strippers, if your teeth aren’t up to the task.
3. Infra-red LEDs, if you want greater accuracy.
4. The lenses from an old Viewmaster (or a new one from here)
5. A PS3 Eye cam or Wii remote (instead of a generic webcam)
6. Soldering gun and solder (for, well, soldering stuff )

Once you’ve collected all that above items, we can begin. Do bear in mind that if you don’t have cardboard, you can even just order a pizza and use that box. As Google themselves have pointed out, order a large
pizza. Preferably pepperoni.

Google Cardboard
Head over to the Google Cardboard website and download the design files. Get print-outs of the pdf on A4 size paper and take extra copies for your friends if you want. Use the scissors to cut out the design from the A4 prints and paste them onto the cardboard sheets. Now, cut out the cardboard using the cut-outs as a template. Obviously, if you don’t trust yourself with a scissors or are too young to do so, get an adult to do it for you.

A snapshot of the stuff you’ll need
…and take a peek through the lenses
3xIR LEDs are key to FaceTrack
Adjust the dimensions till the image is in focus
Place your phone in Cardboard like so…

Once you’ve cut out all the sheets of cardboard, assemble them as shown in the animation on the link mentioned above. It’s very straight-forward and you shouldn’t really be able to mess it up. If you’re unsure
about the layout, simply assemble the contraption with the cut-outs from the A4 sheets to get a feel for the design. Now for the most important part. The lenses that you use need to be precisely positioned in Google’s Cardboard. You can either glue them in place or trust to your cardboard cutting abilities to hold them, but ensure that the lenses are centred and are facing in the same direction (in the case of aspheric lenses). If you’re using the lenses from the ViewMaster mentioned above, you’ll need to rip apart the devices and use the lenses present in the middle of the device rather than the eye-piece lenses. Lastly, download the Google Cardboard app from the Play Store and head over to Chrome experiments for virtual reality.

Tweak FaceTrack’s settings till only 3 LEDs are visible

Place the phone in the Google Cardboard that you built and adjust its position till the images on the device are sharp and distinct. Don’t hesitate to add or remove chunks of cardboard from the design if you feel that it’s necessary to keep everything in focus. Most importantly, strap the phone in place with rubber bands or strips of Velcro and ensure that it’s held tightly in place. Optionally, you can strap a piece of cloth or
Velcro around the Google Cardboard that you built, keeping it stable around your head as well.

Fine-tune the response curves to your taste

What you have now is a fully functional Google Cardboard that will take full advantage of Google’s Cardboard app and their chrome experiments. You can also use the device to watch stereoscopic 3D movies on YouTube and from, ahem, other sources. This is, in itself, very cool, but now, it’s time to push things up a notch.

FaceTrack 2.0

First, if you don’t know what TrackIR is, you’re missing out on something quite fantastic. You can check out a more detailed description in this video:

Now that you’re completely enamoured by the device and have finished staring in horror at the price-tag of a TrackIR 5+Pro Clip, here’s how you build one in just in under Rs 100.

A tracking CLIP

Get yourself three infra-red LEDs. Normal LEDs will also do, but infra-red LEDs are best. Second, you need a decent webcam. The webcam in question needs to have a decent enough resolution and refresh rate
and something like a Microsoft LifeCam should also be fine; we’ve used an Xbox 360 Live Vision cam for our demo. You’ll need to grind the tips of the LEDs using a file or sandpaper or any other rough surface. This diffuses the light and also serves to reduce the overall brightness of the device. Now, solder some wire onto the tips of the LEDs; remember that the longer pin is positive and the shorter one is negative.

The LEDs won’t work if you reverse the polarity. As a rule-of-thumb, use red wire for the positive terminal and black for the negative. It’ll be easier in the long run. Next, solder the free ends of the positive terminals (the red cable) together and do the same for the negative terminals (black cables). Now you can solder these cables to a switch or two AA batteries connected in series. To test if all the connections are fine and that the LEDs are working, you can examine the LEDs with the camera from your mobile phone (when the LEDs are on of course) to see if they’re glowing. Pro-tip: use a battery holder to hold the two AA cells
together. It’ll simplify the job of soldering the terminals.

Now you need to assemble the LEDs into a pattern as indicated by the image above. The dimensions need to be as precise as possible so use a ruler. Place the LEDs at the extremities of the shape shown here and
either glue them on or tape them on. The structure to hold them up can be made of anything, even cardboard, just as long as it holds the LEDs in place and prevents them from moving around. You can attach the
battery pack to the structure you created or you can attach it elsewhere, that’s up to you; we attached it to a cardboard structure, where the cardboard was from an old calendar and thus, very sturdy.

Modifying the webcam The webcam needs minimal modification. You’ll need to power on the infra-red LEDs that you have and use any camera app on your PC to see if the webcam is able to pick up the LEDs. If you don’t see glowing points of light, then it’s likely that your webcam has an IR filter and you’ll have to remove that. You can find instructions for the removal of the IR filter of your particular webcam on Google. After you remove the filter, or if your cam works perfectly as is, place it on your PC and attach the clip that you created earlier to a pair of headphones. Turn on the LEDs, ensure that the camera is able to see your
head in its entirety and that the IR is visible. Head over to the FaceTrackNoIR website, and download and install the program. Run the program, select “PointTracker 1.0” in the “Tracker Source” window and hit start. You should see a tiny image of yourself in a small window. If your clip is on and the software is working great, you’ll see only 3 points in the window, marked with a + sign. If you’re only seeing 3 points, you’re lucky. If not, there’s some tweaking to be done.

A piece of exposed film should be enough of a filter

Here’s how:
1. Ensure that there isn’t any other lightsource incident on the webcam.
2. If the LEDs are too bright, file them a little more and use the PointTracker 1.0 settings to adjust the “threshold” value of your camera till only 3 points are visible.
3. If this still doesn’t work, paste a piece of the data strip from an old floppy drive or an exposed piece of 35mm film across the face of the webcam. This should cut down the light.
4. Play around with the settings till only 3 points are visible.

Once you’ve got the software configured, fire up a TrackIR supported game and you can enjoy the true power and immersiveness of a tool that you thought was forever out of your reach (we’d strongly recommend that you try this out in DCS World, ARMA III or War Thunder).

And here’s the finished tracking clip, ably demonstrated by Mithun

Oculus Thrift

Now here’s the kicker, you can combine FaceTrack with Google Cardboard to make a rudimentary VR device that works somewhat like the Oculus Rift. It’s nowhere near as good as the rift, but it can be made at a fortieth of the cost and is the cheapest way to experience real 3D gaming. You need some software for this to happen, and a rooted Android phone if you don’t have a good Wi-Fi router. Here’s what you need:

If you have an Nvidia card that supports GameStream, then you can get away with Moonlight game streaming on your Android phone.
• If your PC doesn’t support GameStream, use Splashtop or Chrome Remote Desktop or Microsoft Remote Desktop and setup your PC for desktop streaming.
• Download and install Vire.io 

The joy of a real flight-sim can only be experienced with head-tracking

To experience Oculus Rift-esque VR in games:

1. Configure FaceTrackNoIR to run in mouselook mode (Game protocol>Mouse Look)
2. Turn on the IR headset and start tracking via FaceTrack
3. Run Vire.io and run a game of your choice
4. Stream the game to your phone via one of the streaming apps mentioned earlier
5. Place the phone in the Google Cardboard and secure it, strap Google Cardboard to your head

“Splash one bandit!” Shooting down B52s in an Su-27 was never this immersive!

Voila! You now have a rudimentary Oculus Rift that will give you a sniffer of true VR. You’ll still need an Oculus Rift or its equivalent to experience VR the way it’s meant to be experienced, but for Rs 500 or less, this Oculus Thrift provides one hell of an experience.

The article was originally published in the December 2014 issue of Skoar! 


Anirudh Regidi