S3D HMD build

Post by **D4N13L** » Fri Feb 01, 2013 1:19 pm

Hi everyone, I´m new here and I must say I really like what I´ve seen so far.

I wanted to share a concept for a head mount display I´m planning to build and maybe get some input or thoughts on it.
I know lots of hmd´s have been made and that this is not an original idea but that´s why I´m turning to the veterans

The screen I have in mind is a 7 inch 1280*800 res lcd with vga, dvi and HDMI input.
It will reside in a frame attached to an adjustable hard hat suspension that will get further structural reinforcement from industrial earmuffs.
I will then mount speakers in the muffs (maybe try a surround sound setup by putting two sets of earplug speakers in each muff for front and rear audio).
Then so the thing can conform and sit comfortably on the face we have ski goggles and focal lenses to be able to view the screen when it is in one´s face like that.

Below is (hopefully) a demonstration I cut together in MsPaint.
Any feedback appreciated, cheers

Post by **D4N13L** » Fri Feb 01, 2013 4:29 pm

Addition;
I will have an air mouse (gyro mouse) on there for viewing angles, a finger mouse (see below) for mouse buttons and then I will map a numeric pad for movement. (I´m mostly thinking about gaming)
I think I would mount the driverboard on the forehead or even back of the head (if cable length allows) and have all the cables running down the back of the head.
The screen I will use does not have a fragile ribbon cable between the driverboard and the screen but a wrapped cable which I think is fantastic and allows for greater flexibility for that matter.
As for the focal issue I think big strong reading glasses would be ideal as they would put minimal restriction on the fov and allow for gazing from side to side and general freedom of vision.
Then of course weight distribution will be taken into account and I will try to make the frame so that most of the weight is borne by the earmuff strut (or whatever it´s called) and the hard hat suspension will take care of tilt. (so that the thing doesn´t fall off my head when looking down.)

Finger mouse, I plan to tape over the light, as I have the air mouse for movement, and put this on my thumb so that I can click with my index and ring finger like I would a normal mouse.

Post by **D4N13L** » Mon Feb 04, 2013 4:43 pm

Alright, so things are starting to move along. This is my first attempt at a hmd and I´m mainly going for maximum fov. I got two post card size fresnel lenses today and cut them to fit inside ski goggles.
They do deliver as expected, the focus is sharp in the middle and blurs a bit towards the periphery, which I kinda like, but I believe the eyestrain from crossing my eyes to view things, although the lenses do take care of the focus, because the screen is so close will take some getting used to. I can see all the edges on the screen but only just. I will fiddle around and try alternate lens setups and see what I end up using.
I also placed an order today for a 7" 1280x800 lcd which should arrive in little over a week and hopefully I´ll have this up and running in two weeks time.

Here´s a little preivew:

Post by **D4N13L** » Mon Feb 04, 2013 4:45 pm

Btw the display in the pic is my 800x640 tablet, for illustrating purposes only

Post by **D4N13L** » Sat Feb 09, 2013 7:02 pm

Got my prototype together.
It´s a 7" 1280x800 lcd panel, some plastic, a fresnel lens and ski goggles.
The magic is in the simplicity. I hope you guys like it

Post by **D4N13L** » Sat Feb 09, 2013 7:07 pm

my next build will have fully adjustable focus an enclosed control board and no duckt tape

Post by **WiredEarp** » Sat Feb 09, 2013 8:19 pm

Looks nice! Is this a monoscopic HMD?

Post by **D4N13L** » Sun Feb 10, 2013 6:36 am

Yes it is monoscopic, but the fresnel lens creates a starring effect around bright objects and in games where you can set the fov it can deliver quite a decent sense of depth.
In short I am very pleased with how this turned out

Post by **cybereality** » Sun Feb 10, 2013 2:51 pm

Awesome work, man! Looks cool.

Post by **airons1972** » Sun Feb 10, 2013 4:07 pm

Thats great D4N13L, well done.

Post by **WiredEarp** » Sun Feb 10, 2013 10:33 pm

@ D4N13L: The monoscopic could actually be a bonus in some ways, for stuff like FPV etc, and for those who have issues with 3D anyway. The increased resolution due to not splitting the screen would be handy as well. I think the FOV is the most important thing for immersion.

Post by **D4N13L** » Mon Feb 11, 2013 3:17 pm

Thank you cybereality and airons1972

And WiredEarp, I agree

I´ve already planned a few alterations for the next version which I´ll get into quite soon.
1. I want to have the focus adjustable (it´s a fixed housing atm) by making the shell in two pieces so that the eye-to-screen distance can be adjusted.
2. Try a different lens setup to enlarge the image even more (it´s at 90°+ fov now).
3. Make a custom headbrace for better weight distribution.
4. Integrate headphones and a gyro-mouse for head tracking.
5. And hopefully, make it look nice

Post by **D4N13L** » Fri Feb 22, 2013 11:51 am

Just the other day I ran into cybereality´s Perception 3D driver, ran it, opened Skyrim and BAM! it just worked

It is an amazing contribution to the DIY community and he has my utmost respect and gratitude for that

I´ve been playing Skyrim in 3D with a prism I made from a CD case (pic below) and I´ve started to work on a redesign for my HMD to make use of this new found gem. I will post on further progress.

Post by **cybereality** » Sat Feb 23, 2013 12:40 am

Glad I could be of assistance.

Post by **D4N13L** » Mon Mar 04, 2013 11:52 am

Not sure if this belongs elsewhere or not but it is an accessory of sorts for my HMD so I´ll leave this here until told otherwise.
So I wanted to enhance the immersion factor when playing shooter games, dug up my old gun from Time Crisis on PlayStation1 and replaced it´s guts with those of a wireless mouse. I soldered the trigger to MB1 and the two buttons on the barrel (or shaft) to MB2. Then I made a little mount for a wireless numpad I plan to stick on there and map for WASD etc. for movement. There is no tracking on the gun but it does improve immersion to be actually holding a gun rather than a mouse.
Here are some pics

Post by **android78** » Mon Mar 04, 2013 1:57 pm

D4N13L wrote:Just the other day I ran into cybereality´s Perception 3D driver, ran it, opened Skyrim and BAM! it just worked
It is an amazing contribution to the DIY community and he has my utmost respect and gratitude for that

I´ve been playing Skyrim in 3D with a prism I made from a CD case (pic below) and I´ve started to work on a redesign for my HMD to make use of this new found gem. I will post on further progress.

Is that a water filled cavity prism?
The progress you've made on the HMD looks fantastic!

Post by **D4N13L** » Mon Mar 04, 2013 2:11 pm

Yes it is.
And thank you

I am actually right now fiddling around with lens spacing for ipd, lens-to-screen distance, and adjusting Vireio settings in game and will post a pic of the current status in a short while...

Post by **D4N13L** » Mon Mar 04, 2013 4:16 pm

So I went and got myself a 10x loupe which I accurately judged to have two equal strength lenses in it, mocked up a new face piece and got the ipd and focus sorted

Now I just need to find new material for a remake of the whole unit and source a decent strap to mount it on my head.
I also want to extend the screen cable to a box which I´ll have on my belt to lighten the unit and prevent ripping it off my head if I happen to get tangled on the cables

Some pics of status quo:

Post by **cybereality** » Mon Mar 04, 2013 7:23 pm

Nice!

Post by **D4N13L** » Thu Mar 07, 2013 2:00 pm

Just a quick update:
I´ve got the design mostly figured out and tomorrow I´ll go and buy some safety goggles.
Also I got a letter from the mail about my airmouse which has arrived so I´ll pick that up tomorrow aswell

Post by **D4N13L** » Sat Mar 09, 2013 11:02 am

So now I´m about halfway through extending the cable between the screen and the controller board and have confirmed that it still works

so that´s a good thing.
Tomorrow I´ll finish the extensions and sleeve the cable and on Monday I will hopefully find material to make the screen housing...

Post by **D4N13L** » Sun Mar 10, 2013 11:17 am

I just finished extending the cable from the screen to the controller board and I am quite pleased it worked out

The cable has four twisted pairs that seem to transmit the video signal for which I used a cat5e cable, the rest is just regular wire.
I got a "snake skin" sleeve and I think it looks pretty darn nice.
So now I just need material to rebuild the head piece and soon I´ll be happily strolling around in virtual worlds ;P

Here you have pics of just the cable and then the cable hooked up to the screen and controller board.

Post by **cybereality** » Sun Mar 10, 2013 1:17 pm

Awesome!

Post by **foisi** » Mon Mar 11, 2013 8:38 am

Nice work! I have to do the same extension for my project (but twice since I'm using two screen). I just ordered a 5m cat7 ethernet cable that I will cut in 2. Please can you post some details on how you made your extended LVDS cable ? Did you solder the wire on the small connector that plugs into the panel or did you solder on previous wires (I don't know if I explain that correctly). Thanks

Post by **D4N13L** » Mon Mar 11, 2013 10:21 am

Thank you

And yes I´ll do my best to explain.
The wires were wrapped in a fabric sleeve which I cut off to better get at the wires.
I cut the wires roughly in the middle (so I had the end plugs with some wire sticking out) at 1cm offset lengths so I would not get a huge bulk of spliced wires in a single location.
I did them one at a time so as not to loose track of which wires should connect to which.
Just cut a wire, strip the end, pre-solder the wires and splice in the extension wire. Then do the next 1cm from the previous join.
For soldering, you can either use helping hands and align the ends along each other for the smoothest join (which I did for all the straight splices) or you can twist the wires together, solder them and fold the join over.
Then wrap a little electrical tape around each join.
When splicing in the cat cable I stripped the plastic sleeve to accommodate for all the eight different lengths.
The cat was a little more tricky since the pairs are twisted (and that is really important) so I twisted the pair apart just enough to be able to work with the ends, joined one of the wires like before but the second wire I wrapped around the other (the pic below will demonstrate this) twisted the ends together, soldered and folded it over.
Finally I threaded the cable in a snakeskin sleeve and taped off the ends so that the sleeve wouldn´t unfurl.
That pretty much sums it up. If you have any questions feel free to ask

Post by **foisi** » Mon Mar 11, 2013 12:00 pm

Thank you for the detailed explanations

I have another question : is the snakeskin sleeve really useful ? (maybe for shielding the twisted pairs from external perturbations ?)

Post by **D4N13L** » Mon Mar 11, 2013 12:07 pm

No it does not have any shielding. It´s good because you can push the plugs through it by pushing the sleeve together which will make it expand and when the plugs are through you can pull on it to tighten it around the wires and tape it stuck.
But mostly, it just looks cool

Post by **D4N13L** » Mon Mar 11, 2013 12:37 pm

I got some goggles today for the headset. They are "high end" safety glasses made of rubber and plastic and are quite sturdy which is nice.
They´re also roomy enough to allow for glasses inside which is also pretty nice option even though I don´t use glasses myself.
I´m opting for a fixed ipd of aprox 6cm (based on average of male and female adults) with any correction needed done by software.
I´m going to cut a "window" out of the glasses and fit a plate which will hold the lenses in place.
The final layout is still subject to some speculation which mainly depends on the material I find for the shell.
But progress is being made, slowly but surely

Post by **D4N13L** » Mon Mar 11, 2013 4:57 pm

Just made the lens mount, sketched up the shape using the goggles for reference, found some plastic, drilled the holes for the lenses, measured the shape to scale with the drawing and dry fitted.
Will bust out the dremel tomorrow to cut the plastic in the goggles which is very hard and probably brittle-ish so I don´t want to have to apply force to them while cutting...

some pics

Post by **D4N13L** » Tue Mar 12, 2013 6:00 pm

Got some work done on the face piece.
I cut out the window for the lens holder, sanded the inside of the goggles (I´m going to spray paint it black) and closed off the gaps so that it will be really sturdy and dust proof.
Here are the pics

Post by **D4N13L** » Wed Mar 13, 2013 2:05 pm

The lenses are in their holders now, the goggles are drying and half of the screen housing is already assembled.
Now I just need to wait for the goggles to dry before I make the final focus measurements and attach the housing...
It is nearing completion

Post by **D4N13L** » Wed Mar 13, 2013 5:41 pm

Just a few pics of current status

Post by **adoral84** » Wed Mar 13, 2013 8:36 pm

Wow, looks great! You're really turning that thing out fast

Post by **D4N13L** » Thu Mar 14, 2013 11:59 am

Finished the build today and am very pleased with how it turned out

I decided to make it modular so that I can change to a face piece with a fresnel lens for regular movie viewing and change the depth of the mid piece to accommodate the different focusing distance.
I made the focus adjustable by putting a bolt in the screen piece and then a slit and nut on the mid piece but for very near- or far sighted people I would need to swap the lenses and I plan to make the lens holders "clip-on" so that can be easily done.
Also I plan to make another face piece with adjustable ipd later as this setup works well for me.
Anyway I hope you guys like it, here are lots of pics:

Post by **Likay** » Thu Mar 14, 2013 2:23 pm

Nicely done! Quite fast too!

Post by **D4N13L** » Thu Mar 14, 2013 2:39 pm

Thank you Likay

I have had school from 8 to 4 every day and work in the weekend so I´ve been daydreaming this project all the time and working my a$$ off when I get a chance

Also I am a pretty impatient type, when I want something... I want it yesterday, which helps to get things done

Post by **D4N13L** » Fri May 17, 2013 10:09 am

It´s been a while now since I did any work on my hmd but now that I´ve finished my exams I went straight ahead and tore it apart and started rebuilding it.
A little re-cap:
So first I made a monoscopic hmd using a fresnel lens and I liked the shape but it was too bulky (mainly because of the focus distance of the fresnel) and even though the focus is right you still have to cross your eyes to look at the image because it is so close. So that build was short lived.
Then I decided to tackle a stereoscopic build. It worked beautifully but it was just a mockup to get the ipd and focus distance sorted and was by no means the prettiest thing to have on your face. I also encountered a problem with my extended cable, I think because the twisted pairs in the cat5e cable I used for the video were not twisted tight enough so I got some interference.

Which brings me to the current status.
I used my previous goggles which turned out quite nice and made a new housing or whats-it-called, added an elastic band that goes over the head so that the goggles don´t rest on the cheekbones as much, cut half of the circuit board in the motion sensor away and put in a case from a wifi card and am currently designing the lid in which the screen sits.
For the cable I´m thinking about using a DVI cable since it is made to transmit video signals. Have any of you got experience or thoughts about that?
Anyway I hope you guys like what I got so far

Post by **D4N13L** » Sat May 18, 2013 10:05 am

Fitted the lenses back in with a little riser (translate: bottle cap) and took the foam off for replacement.

Post by **D4N13L** » Mon May 20, 2013 8:27 am

Just made the lid and some raised forehead support which makes the thing quite nice to wear.
I also cut a little bit out from the corners of the goggles to better accommodate glasses.

Post by **D4N13L** » Mon May 20, 2013 9:25 am

Finished the headset the other day. Going to play L4D for a while now