Monday 24 August 2009

MyVu Solo displays

Here's the photo of the bits remaining after breaking up the glasses:
From MyVu

The remaining useful pieces are two microdisplays with controller: one and one half-optics sets (I cracked one mirror).
From MyVu

I'd sliced the cable between the two PCBs during disassembly and found that they don't turn on if the second display is not connected, even with a bit of fiddling. Trying to strip the FFC (Flat Flexible Cable) to try and reattach it just didn't work - the connectors are about 0.2mm wide at that point and I just cut more and more off.
From MyVu

Farnell came to the rescue: A 20-way 0.5mm pitch FFC (A to A) for £1.54 did the job just as well. I plugged it in to both displays and they're both up and running.
Here's a mini southpark episode:
From MyVu

Now all I need are some glasses and some magnifying lenses....

Monday 17 August 2009

No disassemble - part 2

Just to finish off the breakdown of the myvu glasses:

Once the outer shell has been removed, you are left with a small plastic unit containing two clear plastic blocks, with the displays at either end. They appear to be solidly glued in.

I ended cutting the block in half using wire cutters. The plastic is moulded in two parts, but is pretty solidly attached or glued. I then had to cut away and snap bits with pliers to uncover the plastic prisms.
Once the prisms are removed, the remaining plastic can be snipped away to uncover the displays and tidy them up a bit. Be careful of the diagonal ends of the prisms - there are small glass mirrors glued to the ends, and I chipped one.

I now have two uncovered displays and two plastic mirror/lenses. They can be re-mounted in a more suitable frame (maybe reprapped?)

Sunday 16 August 2009

Another step forward

Dusted off the old reprap today.

I warmed the heater up and extruded a few cm of 1mm extrusion - through a 0.8mm nozzle, the print quality won't be too good but it should be quick. The extruder actually seems to work reasonably well!

I then had to fix the acrylic Z-axis flag, which has cracked and broken off - the flag holder and also the opto-endstop holder. A big lump of polymorph worked really well at replacing both cracked acrylic parts.

I then had a massive headache so I put it down for the afternoon.

Nearly there - time to try a print soon.

No disassemble Number Five!

Today I took apart a set of MyVu solo glasses to extract the displays. I thought it might be useful to post some photos to help anyone else following my path.
From MyVu

I built my own phono lead to connect a composite source - the cheaper version only comes with an Ipod lead. Pinouts for the myvu solo 4-pole 3.5mm connector are:

Tip - left
ring - right
ring - a/v ground
body/ring - video

This happens to be the same as the Zune media player. Connect the grounds (outer rings) from the phonos to the a/v ground, and the tips of three phonos to the left, right and video.

Starting point:
From MyVu

A bit of experimentation with the screwdriver found that the front cover is held on by a couple of plastic tabs, and with a bit of levering comes off pretty easy.

From MyVu

From MyVu

There is a plastic frame in three parts holding everything together. It is screwed together with four torx screws - two neat the centre bridge, and two behind small plasic covers forming the arm pivots (the hinges for the folding bits).
I drilled these out as my driver was too big, causing a bit of damage.
From MyVu

The signal is generated in the control box and fed up a many-core wire into a small connecting PCB on the left side of the glasses.
From MyVu

The signal appears to be split and sent across to the right-hand display using the (damaged) flat cable. This can be unplugged at both ends. The right-hand end is simpler, only connecting to the right ear piece.
From MyVu

I cut the earphone wires and pulled out the rubber housings from the arms. This allowed me to force the left arm apart freeing the cable.

Currently, the control box still works, although the video is not visible. I think it's because the backlight circuit probably runs through both LEDs in series, so I'll need to identify and patch that so I have a single working, monoptical display. Then I can re-mount it in a more 'socially acceptable' frame to form the HUD for my dataglasses.

Sunday 9 August 2009


I spent a few hours this weekend working on another project...

I've been interested in HCI (Human-Computer Interaction) for a while - it started as part of my job - and I got started with alternative input devices, mainly keyboards and mice when I suffered from RSI/carpal tunnel.

When I read about dataglasses (courtesy of the most excellent writer Charles Stross) I was fascinated. I wanted some. They sounded like such a good idea - a logical extension of wearable computer use, a real integration of the things computers are good at to provide a useful tool.

For the uninitiated, dataglasses are basically sunglasses with an integrated computer display - providing a head-up display - add in net access, camera to provide face recognition, clever software, and you start to get some really cool capabilities. I'll leave it to Mr. Stross to explain the details (and possible problems) in his book Accelerando.

Since no manufacturer seems to be producing them yet, I'll have to build my own.

MyVu MA049 Solo Plus personal media glasses
Old laptop with composite video out
An iphone headphone adaptor plug (Any 4-wire 3.5mm plug will do - like a normal headphone plug but with 3 divisions not 2)
Two or more webcams.

Phase 1:
Get the computer display onto the glasses display.
Actually a bit harder than it sounds - the glasses only come with an Ipod lead (at least the £45 I bought on ebay) and the extra connectors kit is out of stock. It's basically a 4-pole 3.5mm stereo jack, like a headphone plug, to phono plugs.

I found an 'iphone' headphone adaptor in a charity shop which had a 4-pole 3.5mm plug - so a bit of modding is in order.

I investigated the output from the Ipod lead and I think I've sorted the signals.

MyVu Solo plus pinout
4-pole 3.5mm plug

Tip - Left
Ring 1 - Right
Ring 2 - A/V Ground
Ring 3 - Video

I've hooked up the wires with some of my shonky soldering, but it's refusing to play ball so far. The glasses claim to be missing the video signal.

It's still a work in progress....