DIY single hand keyboard

June 1st, 2010


So this is what I was up to lately: The last two days I put together sort of a homebrew FrogPad. A small (17 keys) keyboard with a unique layout for left hand only touchtyping. Since I am writing this on it, I succeeded at least partially.

The whole thing consists of a Microsoft Bluetooth number pad (any other should do fine as well) and the ControllerMate Mac software to remap its keys (and key combinations) to (most of the) regular keys. The alternate key layout is designed for left hand only use with the pad rotated by 90 degrees (0 to the left).

It is an interesting problem how to distribute the chars to different layers on the pad taking character frequencies into account (biased by me doing a lot programming and LaTeX typesetting). Unfortunately it seems difficult to optimize the layout for both english and german typing: Although the set of the 12 most frequent characters seem to coincide in both languages their pairs (which one wants on different fingers if possible) differ.

So it is a compromise. The current layout does not cover the complete ascii set but it does pretty much everything I need (actually maybe it DOES cover ascci with some control-alt-shift-whatever combination).Here is the current layout:


Holding the lowest three buttons for half a second will reset everything (clear all toggles and prefixes – in case one gets lost…)

I swapped [space] and “s” back and forth a lot and I am still unsure: having them swapped is more logical, but the current setup types easier since “n” and “r” are quite common as word endings in the german language.

As an interesting sideremark: I found that the majority of my typos are due to syncing issues between left and right hand (like typing “udn” instead of “und” in german). I am curious to what this will change (since there can not be any such problems anymore, other issues will have to take the lead).

I am not nearly as fast on this as I am with 10 finger touch typing on a regular keyboard but I am already better in memorizing the character positions in my selfmade layout.


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