UPDATE (September 21, 2018): You can experiment with these capabilities using the procedures and apps available here: https://github.com/ChristophGeske/ARCoreInsideOutTrackingGearVr
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When paired with suitable higher-end Google, Samsung, or various other brands of smartphones, the Google Daydream VR headset (currently in its second generation “2017” version, which is the version I’m discussing in this post) offers an extremely inexpensive path for “virtual reality” and other related experiences and experiments (the headset sometimes goes on sale for as little as $50).
In addition to of course being able to display Daydream-compatible VR apps, when a suitable Samsung phone is used it is also possible (via an interesting sequence of actions) to use many Oculus/Samsung Gear VR headset apps with the Daydream headset as well (feel free to contact me if you’re interested in the details on this).
At first glance (no pun intended) one would assume that Daydream headsets are unsuitable for “augmented reality” VR applications that require use of the phone camera, since the Daydream flap that holds the phone in place completely blocks the back of the phone and the camera lens.
This also seemingly eliminates the possibility of Daydream headset experimentation with “inside-out” 6DOF (six degrees of freedom) positional tracking applications, which could otherwise leverage the phone’s camera and Google’s “ARCore” platform to provide these capabilities that conventionally have only been available with far more expensive VR headsets.
We might consider cutting a hole through the rather thick flap of the headset (which also includes an integral heat sink — important when the flap is closed), but that’s messy at best, risks accidentally damaging embedded NFC tags, and is dependent on the exact position of the camera lens for any specific phone.
So here’s my alternative that requires zero modification of the Daydream headset itself, and only a few simple parts to achieve — an elastic strap to hold the phone in place with the flap of the headset left open and the phone camera lens exposed for use. The completed strap is simple to install or remove from the headset at any time, since the flap can be pulled outward to create a gap for this purpose.
To view a set of photos showing the assembly sequence and the finished design, please visit:
I used a piece of elastic that already had a plastic catch on the end of suitable size to hold the elastic in place under the flap hinge. Alternatively almost anything of similar dimensions could be attached to a strip of elastic to achieve the same result.
You simply slide the completed assembly between the flap of the headset and the main part of the headset, strap in the phone, and you’re ready to go. I originally tested this using a metal washer, but decided that even wrapped in tape there was some risk of scratching the phone. A better protected metal washer would probably be fine. I printed up a custom-sized plastic washer to use instead.
The elastic holds the phone in place quite snugly, though with enough violent head motion it might be possible to force the phone to slide out from under the elastic. It should be straightforward to slip little barriers on the sides to avoid this, or simply avoid violent head motions! Also keep in mind that you don’t want to apply significant downward pressure to the open flap, since that would risk potentially breaking the plastic supports that keep it from falling further open.
Anyway, it’s really just the elastic, the washer, and several small cable ties!
OK, it’s a hack. No apologies.
If you have any questions, please let me know!
And of course, be seeing you.