Roie Weiman from Israel built an assistive typing tool for a colleague who had two fingers amputated, making it difficult to type as he could no longer feel the keys.
Weiman built several prototypes to create a 3D printed brace that could attach to the hand and provide enough extension to enable the user to feel the keys when typing.
The device files are available on Instructables for anyone who may need them.
3D printing means the device can be customised for each user and produced cheaply to make it accessible to all.
Weiman recommends using SLS or FDM printers to print the device in PETG or nylon, and for a grippier surface, a silicone cast can be used.