Device Details


The Hand-Raiser is an assistive device used to catch the attention of a professor without a student having to raise their hand. This device would be beneficial for someone who has difficulty or is unable to raise their hand for an extended period of time.


 The Hand-Raiser works by flashing it’s light according to the incoming requests through the USB connection. The Hand-Raiser includes a set of Windows Shortcuts that can be used to change the LED by just double clicking on it.


The Hand-Raiser can work with any computer with Windows.


The Hand-Raiser costs approximately $15.

Build Instructions 

A video on how to assemble this device is linked above. Written instructions on how to program and assemble the device are linked above. Once the device is programmed, red, yellow, and green are automatically added to the Hand-Raiser. If the user would like additional colour shortcuts added to the device, step by step instructions to do so are linked above.

Skills Required

  •  3D Printing Skills
  • Programming

Time Required

  • Total print time: 70 minutes
  • Assembly Time: 10 minutes


  •  3D Printer
  • Computer with USB port


  •  1x Adafruit Trinket – Link
  • 1x USB Cable – USB A to micro-B – Link

3D Printing

All components can be printed with no support at 20% infill with a 0.2mm layer height. There are 3 pieces to the enclosure: a back plate, a hanging hook, and a faceplate.

  • 1x Back Plate
  • 1x Hanging Hook
  • 1x Faceplate – This piece must be printed with translucent filament.

Note that there are several versions of the hook and the faceplate, but you only need one of each.


The code for this device was written by Bill Binko and is licensed under the MIT license.

The Hand-Raiser 3D printed housing was designed by AT Makers and is licensed under the Creative Commons – Attribution – Non-Commercial – Share Alike license.

Documentation for this device was created by Neil Squire / Makers Making Change licensed under the CC-BY-SA 4.0 license.