2015-09-10 (Th) Wrist Mounted Chording Keyboard

Control components were being considered for the servo portion of the project and it was decided to keep the project modular and connect all servo control to a different controller. This removed any scan time used to check inputs and move servos. Servo motors will be the sole force holding the keyboard in place under the hand. It could be possible to push the keyboard away during typing which would cause the servos to push it back into position. At the code level servo movement was controlled by an Arduino library which could have unnecessary delays. Primarily the code for the servos is being put on a different board to modularize the system. With two controllers it could be possible to remove the keyboard hardware, or at least the controller, and still operate and troubleshoot the wrist mounted servos. Light could also be added which would be another draw on the system.


Keyboard schematic

Downloadable Files:
To do:
  • Wrist mount
    • Revise offset levers 
    • Make holes in thumb board cylindrical instead of countersunk 
    • Add limit switch mounts
    • Connect servo arms
    • 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
    • Route wires 
  • Write instructions
    • Compress and link to all files
      • OpenSCAD files
      • STL models
      • Arduino code 
    • Make diagram with everything labeled 
    • Schematic

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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2015-08-27 (Th)

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