Orthocarpus layout

Orthocarpus is ortholinear carpalx optimized layout with preset FJ home keys. Optimizaton is based on reference text containing 5 000 featured articles from English wikipedia.

Orthocarpus layout

In contrast to JNSF layout, vowels are consolidated on right hand side.

k p l r c ⟵ 30.9% ⟶ m u o w x
d s t f n ⟵ 62% ⟶ i j e a h
q b g , . ⟵ 7.1% ⟶ - v y ' z

Home row and top rows are actively used, while bottom row is offloaded.

Load distribution

Ten finger distribution takes into account spaces, line feeds, capitalization and error correction (assuming 96% accuracy). Eight finger distribution is calculated without taking into account backspace, spaces, line feeds and modifiers.

Calculation of typing effort takes into account 26 letters and 4 most common puntcuation characters (comma, full stop, apostrophe and hyphen). Typing effort is 1.982.

Since FJ keys were handled as designated home keys, one can reuse existing DSA, XDA or other uniform keycaps.

Orthocarpus layout

J key is used as home row modifier, it acts as J key on tap and as Shift modifier on hold. Home row modifier supplements left Shift and offloads right thumb which is primarily responsible for space key. All frequent bigrams that start with j are confined to right side of keyboard making it easier to eliminate accidental capitalization.

Other modifiers in the middle can be accessed by both thumbs. Layer keys act as F11 and F12 keys on tap and activate layer on hold.

Full stop and hyphen are accessible by index fingers while typing text and by thumbs while entering numbers.

QMK configuration for ID75 fullgrid ortholinear QMK programmable keyboard is available. It can be compiled locally as qmk compile -kb idobo -km gkbd_75 and flashed in dfu mode. JSON configurations with home row modifier and simplified configuration with one shot Shift modifier can be viewed and modified in QMK configurator.

March 7, 2022. Giorgi Chavchanidze.