A Keyboard and Mouse for Your Finger

There are as many different types of keyboards and mice as there are flavors of ice cream. Whether you are in the market for a mechanical keyboard with customizable RGB lighting or an ergonomic mouse designed to reduce wrist strain, the options are seemingly endless. You can find compact keyboards for tight spaces, gaming mice with adjustable DPI settings for precision, and even wireless setups for a clutter-free desk. For those who type a lot, there are keyboards with different switch types that offer various tactile feedback and sound levels. Likewise, mice come in various shapes and sizes to fit different hand grips and preferences.

But by and large, these devices are all designed to sit directly in front of the user at a desk. For a variety of reasons, like aches and pains caused by arthritis or a repetitive strain injury, that is not always the best solution for everyone. Sometimes you need to kick back on the couch or in a recliner, but still get some work done. And in those situations, finding an input device for your computer that actually works well can be a big challenge.

A Hackaday.io user named Sophia Dai knows this pain all too well, so Dai decided to create a wearable interface device that is both pleasant to work with and usable from anywhere it is needed. The result is a relatively small keyboard-mouse ring called ErgO. It is composed of a handful of inexpensive off-the-shelf components and can be used to control a computer or about any other Bluetooth-enabled device.

Powering the device is a Seeed Studio XIAO nRF52840 Sense microcontroller development board, which provides processing power as well as an inertial measurement unit and a Bluetooth transceiver. This is paired with a Pimoroni Trackball, a few buttons and switches, and a small, rechargeable battery. These components are fit into the base of a 3D-printed ring that enables the wearer to control devices with their pointer finger and thumb.

ErgO operates in two different modes — mouse and keyboard. In mouse mode, finger motions translate directly into on-screen cursor movements. There is also a tiny trackball that can be manipulated with the thumb when greater precision is needed. With a button press, ErgO can be put into keyboard mode. In order to type, the user holds down a button, then traces the letter that they want to type in the air. The trackball is also repurposed to work like arrow keys on a traditional keyboard.

The mouse mode looks to be the most appealing function of ErgO. Dai admitted that typing is a little bit awkward, but where mouse work is primarily needed, with just occasional typing, the ring really shines. Aside from that, the ring is a bit larger than ideal because of the use of commercial development boards, but a redesign is certainly possible with a custom PCB and minimal list of components that are actually utilized.

In any case, ErgO looks like it would be a lot of fun to play with, and maybe even useful. If you would like to try it out for yourself, check out the full, step-by-step build instructions to get started on your own copy of the device.