Design notes
How the exocortex is built and why: the boards and their one pin, the hub, the shell and the beanie.
The designAn EEG helmet you can build: 48 flat circuit boards cut to the shape of the head, carrying 1,273 gold-plated spring pins that press through the hair onto the scalp.
Contact boards and pins48 flat boards cover 89.5% of the scalp with 1,273 contacts.
HubOne board at the back of the helmet: it feeds the 16 main boards' controllers over the 12-pin FPC, powers, syncs and controls the 5 cameras over the same FPC, and links the helmet to a host.
CamerasFive identical boards sit in the beanie's folded cuff: three across the front and two on the slanted back rim.
ShellThe PETG shell carries the boards, the hub, the battery and the five cameras.
Beanie and chargingAn ordinary acrylic 2×2 rib-knit beanie with a turned-up cuff goes over the shell.
Ordering oneEverything to buy for one exocortex, from whom, and every option on every order form: $11,784.14 all in.