Hey all, in this update I will be breaking down extensions further to some extent!

Keyboard

Here is a breakdown of all the parts in the keyboard extension

1. Plastic Keys: These are the individual plastic keys, in the manufacturing process we are carefully painting the keys white and then adding a black coat and then applying laser etching to print the characters. This way the keys are readable without backlight and can glow with the backlight too. These are simple plastic designs, you should be able to print your own keys.
2. Dome Switches Sticker: These oblong dome switches help give the tactility to the keys, we originally ordered them without checking their operating force specs but then course corrected, these new ones have an operating force of ~100g.
3. Silicon Base: The silicone layer is used to create the travel for the keys and are placed between the keys and the dome switches. This is where we messed up, our silicone is too thick, making it really hard to press 🙃. Our mechanical team fixed this for the demo by getting rid of this and adding a small PLA part inside each key, and this is what you see in the demo video. We are now evaluating if that could be used in production as well.
4. Keyboard Mainboard: This is the main board for the keyboard with a STM32 G series microcontroller, paired with an Azoteq IQS9150 trackpad IC. The extension communicates over USB via the popular QMK firmware for Linux. This means you can simply use Vial (https://get.vial.today/) to remap the keyboard layout without reflashing. For reflashing we are testing flashing via the Comet. All the backlight LEDs are also integrated with QMK and we are now trying to add trackpad support.
5. Trackpad Flex PCB: This trackpad flex pcb sticks to the housing from the inside and uses a simple flex pcb connector on the board. We have tested the trackpad, it works well! ✌️
6. Pogo Pins: Our custom pogo pins that get soldered on the back of the mainboard
7. Magnets and Metal plates: To maximize horizontal space while keeping the form factor the metal plates are used

All this fits inside a 5.00mm housing and we use the same screws as the Comet making it easy to open it up. We will set up the repository soon for the keyboard, but for anyone curious or wants to dig more here is the 3D CAD for the keyboard -

Gamepad

This is the actual parts breakdown for the gamepad as well. Similar to the keyboard the gamepad also uses a Trackpad Flex PCB (2) but keeping the additional D-pad tactile. We are right now working on moving the gamepad firmware also to QMK with a Gamepad HID instead of keyboard, making it easier to remap like the keyboard. We will share a demo soon, sometime this month! The Gamepad also sits inside a ~5.00 mm housing, here is the 3D CAD for the gamepad -

IO Breakout

One of the things we want to do in October is to finalize the IO extension but we want to design and build it with everyone here. We need all you tinkering experts to help us design the perfect prototyping extension for the Comet. We will start the thread on our forum and track its progress there!

What our design already includes

• Make all the pogo pins available as 2.54 mm female header pins
• Provide easy access to serial console using an embedded Serial to USB converter

What we want to further cover

• Add general-purpose / breadboard like features for users to be able to hand solder parts easily, even through-hole parts
• The extension should work without top cover, users should be able to design a custom top cover for their end-use
• The extension should have some generic controls like leds, buttons, rotary encoders that users can use for their prototypes.
• Add an integrated CAN controller and a terminal connector to allow user to insert wires.
• Users should be able to use the IO extension as a base to test their custom extension design before making the final one.

Hopefully this will help everyone in the community also understand how the extensions are actually designed and maybe help them design their own!