My goal was simply to see if I could make something that matched and hopefully exceed the physical comfort of the current “dive mask” Head Mounted Display (HMD) concept used by Oculus. Ultimately I would like to build my own HMD from scratch but will iterate towards this piece by piece. The Oculus Dev Kit 1 is a great starting point as I can explore physical HMD characteristics without getting bogged down in all the electronics, optics and software (yet).
The Result (Yay!!)
After many (many) iterations I was finally able to complete my first fully functional Head Mounted Display using the electronics, screen and lenses from a Oculus Rift Dev Kit 1 headset.
Lens and screen mount
I created five separate lens mount variations and ended up using the one shown below. It is nice and stiff while still being quite light and held the lenses firmly in the correct position. The base of each cup exactly matches the shape of the rendered images in the standard farmhouse demo (which just shows how much of the screen real estate is wasted in this version). The nose rest slides into a square tube and is replaceable. The lenses are those of from the Dev Kit and are held firmly in place by two, friction fit, rings. The screen and accelerometer are held snugly in place by a back plate which is attached to the back of the eye cup component. The eye cup piece shown is printed as one piece and took around four hours to print. The back plate was also printed as a single piece.
I found the job of actually making a comfortable head mount quite daunting. I built a number of prototypes using combinations of elastic straps, headbands, a tight-fitting beanie as well as printed components but none of these provided both comfort and a good physical mounting point for a HMD. I finally opted for a quick workaround in the form of an insert from a safety helmet from Home Depot. The insert was not useable as is so I built some clasps that fitted exactly into the insert to form an adjustable X-shaped crown. Once complete the insert worked well; it was adjustable, comfortable and quickly disappeared into the background like a well-fitting hat. It also had two “studs” that protruded from either side of the headband at the widest lateral position as shown which I was able to use as the mounting points for the screen assembly.
Adjustable Screen Mounts
The two side assemblies proved quite challenging to make light, strong and adjustable. This assembly, that joins the head mount to the screen, has to allow for horizontal rotation, axial rotation and length adjustment as well as being rigid and light. My solution was to break the side mount into two sliding rails, a rotating end connector and a head mount clasp as shown.
Putting it together
All the various components fitter together easily using standard fasteners available from any hardware store thanks to the precision of my wonderful Printrbot Plus.
Fully assembled the whole thing weighed around 200 grams without the Oculus electronics.
Testing it out
I really liked the experience wearing the completed head mounted display. The adjustable headband was super comfortable, I did not have anything touching my face apart from the nose rest and did not get the “hot face” that I get very quickly with the standard Dev Kit 1 mount. The one weakness of this design is that the full pivoted weight of the display had to be carried by the nose rest making it uncomfortable to wear after a short period of time.
I had the chance to show the display at our awesome local Vancouver VR meetup and received a very positive response from the group, many of whom had a chance to try it on. They all agreed that the weight on nose rest was the one failing, but, apart from that, found the experience very pleasant. The lack of blinds to block out peripheral vision actually received a positive response from several testers. They felt that it was not at all distracting and, in fact, allowed them to sense when others were approaching them so they could remove the headset and be social. Interesting.
The key focus will be to reduce the weight of the pivoting screen mount as much as possible as well as look at ways of moving the weight away from the nose, perhaps onto the cheeks. The rest of the device is working well. Once I have worked out how to have the nose rest have just the right amount of force to keep the eye pieces registered correctly with the face and the remaining weight taken up somewhere else I will move on to making the optics adjustable. Any comments and suggestions are most welcome.