2015-08-12 (W) Wrist Mounted Chording Keyboard

Servos were set into the printed mounts and printed servo lever arms were attached. Each of the servos was connected to a tester so they would move but their motion was opposite not synchronized. This motion was only for demonstration since the operating version will have the servo levers moving synchronously. Movement was not captured accurately; the servo arms appear to be flexing during movement but they remained rigid.

Demonstration of servo movement

1/4" nylon cable holders were purchased to hold the 8-wire cable in place at the back of the keyboard. Unfortunately the cable was smaller than the diameter of the cable clip. Electrical tape was wrapped around the section of cable to be clamped until the diameter was sufficient. The long bolt holding the back end of the keyboard was removed along with the separating washers. The cable clamp replaced one of the washers so the cable could be secured. Both the current keyboard print and cable clamp were shiny black so they matched well.

Increasing cable diameter with tape

Cable clamped in place

To do:
  • Wire Arduino Micro with RJ45 end
  • Program Arduino Micro to act as wired keyboard
  • Add SoftwareSerial port to Micro to send ASCII data to Bluefruit.
  • Use the  SoftwareSerial port to "type" data to the USB keyboard.
  • Route incoming data to Bluefruit as well.
  • Modify servos for continuous rotation.
  • Automate wrist mount.
  • Secure Ethernet wire with a cable clamp
  • Make model and OpenSCAD code public
  • Write keyboard code

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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2015-08-11 (Tu)

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