2015-09-15 (Tu) Wrist Mounted Chording Keyboard

The RJ45 end was stripped off the controller and the eight wires were separated. Each end was stripped back a little bit and tinned so it could be coupled with a wire from one of the switches in the enclosure. Connections were insulated with small diameter shrink tube. A small piece of stripboard was cut out and used for all the ground connections since over eight were needed. Connecting all the switch grounds to one another in a daisy chain fashion would have worked as well.

Eight exposed wires

Switch connections all made and shrink wrapped

Unlike previous versions a battery was added to the design. A 23A battery was used because it was the smallest dimension battery over 5V which wasn't a lithium cell. Battery holders and batteries were stocked. USB connections were not extended to the outside of the case and until that is done the keyboard only works as a Bluetooth keyboard. Desktop versions have been explored. <Hint>

23A (12V) battery holder. Also fits N (1.5V) size batteries

Ergonomics on this keyboard were low but the addition of a battery made it highly portable. Using the keyboard with the palm up allowed for easy operation but typing speed still lagged. Some of the plastic was trimmed from below the switches using a razor saw. Ergonomics have been ignored in favor of portability and finishing the project soon but should be revisited.

Trimmed plastic below buttons and razor saw

First text sent from keyboard

Downloadable Files:
To do:
  • Wrist mount
    • Add limit switch mounts
    • Lengthen servo arms
    • Integrate:
      • Controller
      • High precision potentiometers for tuning servos
      • Servos
      • Enclosure for each controller
      • Limit switches
      • Activation switch
    • Debug 
    • Test
    • Refine
    • Repeat
    • Activation switch
  • Write instructions
    • Compress and link to all files
      • OpenSCAD files
      • STL models
      • Arduino code 
    • Make diagram with everything labeled 
    • Schematic for servo controller

The rest of the posts for this project have been arranged by date.

First time here?

Completed projects from year 1.
Completed projects from year 2

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2015-09-14 (M)