Note: You'll want to be careful handling certain parts of the build. The mechanically weak points of the hardware are:
- The Pi Zero camera cable. The connection to the Pi can pull out when you try it on the first time, and
- The bone conduction transducer. The heat shrink will move the point of failure from the transducer itself breaking to the wires popping out of the audio hat, which is an easy fix.
First thing: solder your 40 pin header onto your Pi Zero 2.
Bone conduction transducer mounting
Gather the following:
Safety glasses
Bone conduction transducer
1x 4" piece of 2mm heat shrink
2x 1.25" piece of 1/4 inch heat shrink
1x 1.25" piece of 3/4 inch heat shrink
Put the 4 inch piece of 2mm heat shrink on the transducer wires and move it close to the transducer without putting tension on the connections and use a heat gun to snug it up to the wires.
Put one of the 1/4" pieces on heat shrink over the right side of the glasses frame then use the heat gun. This layer will help the others stay in place.
Use the 3/4" heat shrink to attach the transducer to the frame. Place the transducer inside of the heat shrink and slide it onto the frame. The transducer should be oriented with the rectangle facing your head and the transducer on the same side of the frame as your head. This is what it's going to look like after you use the heat gun.
Take the last 1/4" piece of heat shrink and put it over the transducer wires and over the frame. You'll want to push it on the frame until it just reaches inside the 3/4" piece then shrink it with the heat gun.
When you are done, it should look like this. Don't forget to cut a hole on the outside of the frame for the head strap of the glasses, it doesn't have to be perfect, just make sure the strap fits on.
Attach the audio hat to the transducer. A small flathead screwdriver will be needed. You will want to put some of the wire casing into the terminal so that it doesn't pull out easily, then attach the audio hat to the Pi.
Attach the camera to the camera cable adapter then zip tie the camera cable adapter to the Vufine. I have made two of these prototypes, one of the cameras had an adhesive backing and one did not, so you may or may not need a little double sided adhesive to mount the camera to the Vufine.
Attach the Vufine mount to the glasses as close to the hinge as possible. This picture shows the maximum distance you want to be from the hinge, closer is better.
Take the glasses under the hat and have the hat right side up. The Pi is mounted to the hat strap with 2 zip ties, the bottom of the Pi goes against the strap of the hat. Make sure it is centered before tightening them.
Take the camera cable and your choice of clips. I used 2 paperclips, but you can use whatever you like.
The camera cable is going to go into the Pi, then 2 clips evenly spaced from the Pi to the start of the brim of the hat.
You will have to bend your camera cable a little. The first bend is at the paperclip located near the brim, then bend it towards the front again. The cable will look like this.
Finishing up
Turn the hat/glasses upside down. Attach the micro to micro USB cable and the micro to mini HDMI cable.
The last step is to attach the straps for the glasses, the straps are optional. The straps help with the bone conduction audio. With the straps on, the audio sounds like you have a headphone in your ear. Without the straps it is still pretty good, the sound quality doesn't change, the intensity does.
