2015-09-02 (W) Wrist Mounted Chording Keyboard

Lever arms were modified to accommodate the protrusions from the keypad. When the device folds back into the retracted position a straight bar would collide with the thumb switches or the folded keypads. It would be possible to extend beyond the switches and pads but the device would get unwieldy.

3D model of servo levers

3D models have been receiving frequent updates and since none of the models have been guaranteed the linked files at the bottom of the page will not be updated until the models have been decided upon. When the models get completed they will be stored as a single .zip file.

Printed pieces were held up to the keypad and tested for a fit. Several problems were noticed, none of which should have been difficult to fix. Measurements taken for the offset piece were exaggerated and should be tightened up. At the rear hinge point the hinge is below a keypad when it is folded and this will cause a collision when the device is retracted. Holes for the bolts to pass through are too large and should be shrunk. Since the rear hinge is being used it should have a servo style end on the back of the model instead of a simple hinge.

Extended position

Collision with folded keypad

Areas which need to be revised

Downloadable Files:
To do:
  • Wrist mount
    • Revise offset levers 
      • Shorten offset distance
      • Allow rear bolt hole to bend around
      • Replace far end of lever with servo end
      • Shrink hinge hole radius
      • Make holes in thumb board cylindrical instead of countersunk
    • Integrate:
      • Controller
      • Servos
      • Enclosure for each controller
      • Limit switches
    • Debug
    • Test
    • Refine
    • Repeat
    • Activation switch
    • Route wires
  • Write instructions
    • 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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2015-08-31 (M)