At the last I / O conference, Google revealed its version of cardboard virtual reality glasses. In principle, schemes for such glasses have long been on the Internet (for example, FOV2GO ). However, the guys from Google turned out to be simpler than their counterparts, and they also added a chip with a magnet that works like an external analog button. In this post I will share my experience of assembling smartphone-based virtual reality glasses: Google Cardboard from cardboard, OpenDive from plastic and glasses cut on a laser cutter from acrylic.

Materials

1. Cardboard. I used an unnecessary laptop box. Another option is to order your favorite pizza or buy cardboard in a special store (searched on request for E microcorrugated cardboard).
2. Velcro. Bought at any sewing store. I took a tape of adhesive tape for 100r. This tape is enough pairs for 10 points.
3. Magnets. In principle, this thing is optional if you do not plan to use the Google API. Google itself recommends taking 1 nickel and a second ferromagnet. On our Internet such magnets in bulk in specialized stores, but I was too lazy to wait for the order. As a result, in the same store I took a set of magnets for fasteners, however, they did not work perfectly for me. Cost - 50 rubles for 3 magnets.
4. Lenses. In general, it is recommended to take lenses 5-7x, 25mm diameter, aspherical. The easiest way to get a magnifier with two lenses, like Veber 1012A, is cheaper than buying 2 identical ones. At my fingertips there was only a magnifying glass 30x with two lenses of 15x each (I took such a magnifying glass on the market for 600 rubles). Despite the overestimated increase, it turned out well.
5. Elastic band and carbine. It will be needed if you plan to use Cardboard as glasses, and not keep them in your hand all the time. I bought in the same sewing store for another 100 rubles 2 meters of elastic and a couple of carbines.
6. Foam rubber. So that the glasses do not hit the face, it is worth pasting foam rubber at the points of contact. I used tape to warm the windows. Another 100 rubles in the construction market.

The final price of materials: 400-1000r depending on the lenses.

Tools

1. Stationery knife.
2. Hot melt adhesive (gun). Better small.
3. Stapler or thread with a needle.

Assembly

Here, in general, everything is trivial.

1. We go to the Google Cardboard website and download the scheme for cutting. If you suddenly have a laser cutter on hand - you can cut it on it. If not, then print on the printer and cut it out.
2. Fasten Velcro. In addition to the two Velcro tabs in the original, I added one on the left side so that the structure would not part. And also glued two Velcro on the sides, on which in the future we will glue an elastic band for attaching to the head.
3. We insert the lenses, magnet and collapse the design.
4. Fasten 2 pieces of elastic to Velcro. At one end, we insert the carabiner at a fixed distance (on an elastic band I fixed it with a stapler :)). On the other side we take a rubber band with a margin and fix the second part of the carbine with the ability to adjust the length.
5. Success!

However, when I installed the application, I found that in this form my button does not work. To activate the press, I had to take a magnet in my hand and drive it directly on the left side of the phone, however, even so it works every other time. A sign that you are doing everything right - when you touch, there should be a sensation of a magnetic field that slightly repels the magnet from the phone.

Perhaps the reason is that I took a magnet too weak. It is possible that my model (Galaxy Nexus) is not declared by Google as supported. However, the demos work, the button is pressed, cheers!

Plastic model

If you want to take a steam bath with the assembly to a minimum and you have a 3D printer (or enough money to order a print), then this option is for you. :) I printed the model from the Thingverse website. There, at the request of "virtual reality" there are several more similar options.



I ordered printing at the 3D Printing Laboratory , I got about 3000r.

All materials from Cardboard are relevant for these glasses, so the final price tag reaches almost 3500r.

Assembly of the model from plastic

We insert the lenses, glue the foam rubber, for fixing the phone we take the usual office rubber bands. You can also stick foam rubber to the entire surface outside the lenses, then the light from the smartphone will not interfere with you. In such glasses, you can also insert larger lenses.



Another option: insert lenses from the Soviet stereoscope. To do this, you will have to slightly modify the mount, replacing round holes with rectangular ones. The option with a stereoscope is quite convenient, but it has a minus - the work area is smaller, the image is cropped from above and below.

Model made of acrylic (or plywood)

Even before collecting virtual reality glasses became a trend, a remarkable scheme of glasses cut out on a laser cutter appeared on the network. Without thinking twice, I decided to order their cutting in the same laboratory. They did not have plywood at that moment, and they offered me to cut out black acrylic. The cost of cutting together with the material turned out to be about 800 rubles.



In addition to lenses, rubber bands and foam rubber, for assembly you will need about 20 screws with 3-4mm nuts (the author of the model suggests using 4mm, but I had difficulty entering them and I took 3mm).



Oddly enough, the final version was even better than on a 3D printer. Firstly, glasses are lighter and more compact. Secondly, the material is smoother and more pleasant to the touch. Of the minuses - acrylic is a fairly fragile material, and such glasses may not survive the fall.

Conclusion

Unfortunately, the content for such glasses is still quite small. You can try to play with streaming, as described in a recent article on Habré. Google Play has simple apps that support DurovisDive and the Cardboard demo . In my opinion, now it’s worth collecting points if you want to write something yourself. For Android, there is a Google Cardboard SDK . Under Unity, there is a DurovisDive plugin that works with Android and iOS. If you have WinPhone8, then at DevCon 2014, among other things, I talked about how to get the simplest virtual reality application for Unity on WinPhone8, watch from the 14th minute.

Have a good dive! :)