Not everyone can drop a few hundred dollars on a VR headset, but that doesn't mean they can't experience VR! For those with the time and a bit of handiwork skill, this DIY guide from guest writer Ohaple will show you how to make a smartphone-based VR headset for as little as $20. Along the way, you'll learn the hardware and software basics of a VR headset. Update (1/21/2016): An update to this guide provides new methods for lower latency gameplay using wired display mirroring software and a gyroscopic mouse for headtracking. Check it out here. Original guide continues below. Virtual reality is on its way into the mainstream. As we see huge shifts such as the Oculus-Facebook buyout and Sony's Morpheus VR headset prototype, virtual reality is making its way into the hearts and minds of gamers everywhere. One problem still stands between the average consumer and a fun virtual reality experience: cost. Whether you follow a guide to create a DIY Oculus Rift or go out and buy the Oculus Rift DK2, you will find your wallet a few hundred dollars lighter. For those wanting a less expensive way to experience VR, using an existing smartphone for the basis of a VR headset greatly reduces the cost. In this guide, I'll show you how to make your own smartphone-based VR headset. [caption id="attachment_11340" align="alignright" width="325"] Durovis Dive Smartphone HMD Adapter[/caption] This DIY VR headset (also known as a head mounted display or HMD) takes a few hours to setup, and will cost somewhere between $20-$50 depending on how you source your parts and whether you want additional programs or controller support. If you already have a Durovis Dive, or would like to buy one, this project can be used with the Dive as well, just skip to the LED installation portion. The Basic Concept: We will build a cheap and easy HMD, similar to the Durovis Dive. We will use our computer to play stereoscopic 3D games. These can include Oculus Rift games, game mods (such as Minecrift), or games compatible with TriDef 3D, which takes 2D games and plays them in stereoscopic 3d. We will then use our iOS or Android device as an external mirrored monitor to view the game in the VR headset. Using an LED, we will establish head-tracking to control your computer’s mouse, and consequently your character’s head position in-game. 1. Measuring and Cutting Parts and Tools: (1x) Sheet of black foam board Hot glue gun and hot glue (1x) Pair of full metal frame reading glasses (for the frames only) (1x) Pair of magnifying lenses. I used the frontmost lenses from a pair of binoculars ($3 at a thrift store) but if you are going to source them on the net, look for aspheric lenses with 5x magnification and about 1-2 inch diameter. 4 feet of inch wide elastic Dimension Overview: First, you need to determine how far your phone will need to sit from your face. Use your lenses to measure about how close the lenses give a good crisp focus. Mine took about 2 and 1/8 inches. This is the distance from your lenses to your display. Measure the width of your reading glasses hinge to hinge onto the foam board. This will be the width of your HMD. Now that you have the focal length and the width, cut out 2 pieces of foam board as wide as the glasses, and 1.5x as long as the focal length. This is the top and bottom. of the unit. You can also make the bottom piece 1/4 inch longer than the top, to allow a shelf for the phone to sit on. If you don’t. you can add it as a separate piece later. Use a plate, or other round object to draw out a semi-circle on the top and bottom pieces. This is to allow it to fit nicely to your face. On the bottom piece, cut out an extra inch or two in the middle to allow venting under your nose (if you don’t, the lenses will fog when you breathe through your nose). Cut out 2 side pieces. They should both be as long as the top and bottom are (1.5x the focal length), and as tall as the front pieces are (the height of your phone in landscape mode. Mark the focal length on these pieces. Cut out 2 front pieces. One of them will be solid, used to cover the back of the phone (to prevent false positive light sources from reflections on the gloss back of the phone). This is not needed if the back of your phone is non-reflective, or if you have a non-reflective phone case. The second one will have a hole cut in it the same size as the display of your phone, centered. These should be as wide as the top and bottom, and as tall as your phone is when in landscape mode. You have all of the foam board cut out to size. Using hot glue, secure the top and bottom to the two sides. Then add the front piece with the cutout, and glue it in place. Make sure that you have left a shelf for the phone to sit on on the bottom piece, or add one now to the very bottom of the unit. This is to prevent your phone falling out the bottom. Glue the second front piece onto the edge of this shelf, making sure there is still room for your phone. Pull the lenses out of the reading glasses. Pressure fit your new lenses into the frames, and glue in place. Now for the lenses and elastic. Holes should be cut approximately 1/2 way up the side panels, at the focal length of your lenses. Now cut the glasses at the hinge, and fit them through the two holes. Glue in place. For the phone holder, glue a strip of elastic across the front of the unit. Be sure not to cover up where your phone charges, as you may need to plug in when you play long sessions. For the headstrap, secure a length of elastic to both sides using hot glue. Two strips may be required to hold it secure. You now have your completed HMD. Now to solve head-tracking. Put the phone in the elastic at the front, put it on, and see how it works. Go to the Durovis Dive website where you can find many apps intended for phone only so you can see how it works. Continue reading on page 2... 2. Wiring the LED To set up head tracking, we will be using an LED-based model. This model uses a webcam to detect LEDs, and track their motion. We only need one LED for this. Many suggest using infrared LEDs. Webcams can detect IR very easily, so by removing the IR filter on a webcam and then installing a visual light filter, IR LEDs can give an excellent result. That said, you can make this work reliably using only a bright-white LED and no webcam modifications. Parts: 1x Bright white 5mm LED (or IR if you will be doing webcam modifications) 1x Watch battery OR 2 AA batteries with the proper battery holder. 1x Small toggle switch (not needed if you are willing to take batteries in and out Tip: If you do not have soldering experience, use the LED and watch battery, it requires no experience or soldering equipment First we will be filing down the LED tip. LEDs are designed with a focusing lens built in. By using a file (or even the concrete outside) flatten the tip, and then buff the sides so they are not glossy. This allows the LED to be seen easily from any angle. The Easy Way: If you have no experience in soldering, you can simply tape the LED to the watch battery. Make sure to have the proper orientation, LEDs only work in one direction. If you got a typical 5mm white LED, a single watch battery should power it with nothing else needed. When you want to turn it off, slide a piece of paper between the battery and the side of the LED that you did not tape. It should look like this. The 'Right' Way: If you want a switch, long lasting batteries, and have soldering experience, this method is for you. Using a battery pack with 2 AA or 2 AAA batteries, solder one pole of the toggle switch to one of the battery terminals. Then use a length of wire approximately 6 inches long to connect the switch to the LED. Then use another 6 inch long length of wire to connect the LED back to the other battery terminal. Test the switch, it should turn the LED on and off. Now that you have the LED wired in your chosen way, use hot glue to secure the LED to the front of the HMD. Make sure that the LED sticks out from the front of the unit for maximum turning radius. Continue reading on page 3... 3. Setting Up Head Tracking Now that the LED is wired onto the HMD, we need to set up head tracking. To do this, we are going to be using Free Track to get point tracking going. Free track does not work with all webcams. If your webcam is not supported, you can use Many Cam as a middle man to get it to interface. Get Free Track Here Get Many Cam Here To get Free Track working properly, you will need to do a few things. First, your environment matters. It should not be a brightly lit environment with many bright spots. A medium-lit room works great, as long as there are not reflective surfaces in view of the webcam. Next, choose your webcam. Go to Setup, and choose the Single Point model. Now adjust the threshold under the Cam tab. If you cannot get only the LED to be detected, you may need to adjust your room environment or dim the lights further. A pitch black room may have problems with internal reflections from the LED in your webcam lenses. For further help, reference the Free Track handbook. Now in the Output mode, select mouse emulation. You may need to adjust the pitch and yaw sensitivity different for different games. You can set up different profiles to make it easy. Turn on your LED, click start, and move the LED around in front of the webcam. You should see it move your mouse. If it does, you did it! 4. Playing 3D Games to Your Smartphone VR Headset Now we need to get the game into our head-tracking HMD. We will be using our phones to accomplish this using a software package called Splashtop. You can download the desktop app for Windows or Mac for free here. Using the same link, you can download the app for your mobile device. The app does cost a couple bucks for mobile. For Android they also offer a gaming-specific app, but it isn’t necessary for our use. Follow the setup on both apps, and your display should easily be mirrored on your mobile device. For best results, change the resolution of your computer display to be the same aspect ratio of your mobile device. Make sure that your mobile device and computer are on the same network. Now you need to get 3D games to play on this HMD. I have found four ways to do this so far: 3D Game Drivers such as TriDef 3D. Game mods such as MinecRift Native 3D games Oculus Rift games with horizontal and vertical mouse control Here are a couple resources for games: Oculus Rift Games list at RiftEnabled MinecRift Mod TriDef3D compatible games list Controller Support (Optional) An additional feature you can add to your experience is controller support. Using an Xbox 360 wireless controller, wireless adapter, and compatible program, you can use a controller to allow easier gaming, and wireless gaming (similar to Nvidia shield). I use Keysticks to get my controller to work in games. A program like this is needed, because most games allow controller support or mouse control. Since our HMD uses mouse control, we need to have the controller use the mouse as well. Get Keysticks here. You can see the controller working in this setup here: If you have any questions, feel free to contact me on YouTube.com/ohaple, I check my private messages frequently. I am always working to improve this design, so be sure to send any suggestions along. Keep in mind that the primary goal of this project is to be affordable for anyone of any class. I have done my best to also make this technically accessible to people who do not have any technical background.