2015-09-30 (W) Wrist Mounted Chording Keyboard

Measurements were taken and a list of necessary spacers sizes was made. Spacers will be used again to make standoffs for each piece rather than reprinting with spacers included. After considering the benefits of modularity it may be logical to keep spacers separate from the pieces and print them separately in the future.



After assembly faults in the measurements and calculations became obvious and overlapping parts produced a shortage again. Measurements to make the servos sit close enough to touch resulted in the three center spacers being too short and one of the spacers which was meant to go between the main chassis and the stand-off hinge base was overlapped by another part in the model and not printed. Calculations for the keyboard holder spacers were accurate considering the width of the servos and the servo levers.

Available pieces assembled as well as possible

Keyboard and spacers shown above servos

Spacers were remodeled and reprinted which allowed a functional prototype to be constructed. Proper bolts weren't immediately available so threaded rods were used. Motion was fluid but the spacers for the hinge levers were still short. Straight hinge levers also interfere with the servo levers which can be modified if the interference is excessive.

Functional prototype with threaded rods

Downloadable Files:
To do:
  • Wrist mount
    • Servo arms
      • Bend around spacers
    • Terminal board
      • Input voltage
        • USB
    • Make base for keyboard
      • Spacers
    • Integrate:
      • Enclosure for each controller
        • Potentiometer access
      • Activation switch
    • Debug 
    • Test
    • Refine
    • Repeat
  • Write instructions
    • Compress and link to all files
      • OpenSCAD files
      • STL models
      • Arduino code 
    • Make diagram with every part 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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2015-09-28 (M)

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