2015-09-23 (W) Wrist Mounted Chording Keyboard

Servo control was finally solved with the Arduino Pro Mini. Significant changes to the program weren't made so the Digispark was not an appropriate choice. This may have been due to the lack of built-in pull-up resistors or a populated communication pin. Size and cost differences were negligible so the decision to change controllers was not difficult. Code for the Arduino Pro Mini was also able to be written, monitored, and uploaded through codebender.cc and that code is provided here.

Operation of the servo motors went well. A wire was bridged between the switch terminals to simulate position changes and limit switches. When the position switch is pressed, momentarily, the direction of the servos should change to extend or retract. When the appropriate limit switch is pressed it tells the controller that the device is in location and it the servo can be turned off.  A video was made to demonstrate the function of each of the inputs.

Tangle of wires and programming hardware

Video demonstration of servo controller

Downloadable Files:
To do:
  • Wrist mount
    • Make longer straight servo arms
    • Make base for keyboard
    • Integrate:
      • Controller
      • Servos
      • Enclosure for each controller
      • Limit switches
      • Activation switch
      • Power connection
    • Debug 
    • Test
    • Refine
    • Repeat
  • 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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2015-09-23 (W)