Omar Alinur, Evan Hill, Hajin Kim, Jiaxuan Li

High Level Description:

  • What is it –  A whistle that lights up and makes noises when swung. As the whistle is swung faster, it makes a louder noise and more lights light up.
  • Target Audience – Children 7+ (~First Grade) Children at this age know how to formulate correlations from what they observe from the social world. They also work with 2 dimensional and 3 dimensional shapes.
  • Children Interaction – In an open environment, the user will swing the whistle at different speeds to examine the correlation of velocity, sound, and light intensity.

Learning Goals:

Through swinging the whistle, the concept of centripetal force can be learned. The increase in loudness and the number of LEDs lit up will help reinforce this concept. Also, as the whistle continues to move when the child stops swinging it, he/she can learn about the conservation of momentum. In addition, the child can explore the relationship between shapes and air flow.

Operation Info:


  • Swing at arms distance away to avoid injuries
  • Watch out for surrounding people and objects
  • Should be used outdoors in open spaces


  1. Hold the whistle by the strap handle tightly
  2. Turn on LEDs
  3. Swing whistle in a circle and observe lights and sound

    How do you make it?

  • Material – Gray PLA, 4 Red LEDs, 4 Yellow LEDs, 4 Green LEDs, 3 220ohm Resistors, GY-61 ADCL335 3-Axis Analog Output Accelerometer, Arduino Pro-Micro-Controller
  • Cost – $7
  • Manufacturing Processes-
    • Body- Solidworks CAD Modeling -> NVBot 3D Printing -> Electric screw driver to remove support material
    • Circuit- Accelerometer -> Arduino -> Parallel LED Circuits

    • Tie string to body holes and adjust length according to user height
  • Core Technology Explained –
    • The accelerometer measures the change in the xyz orientation as raw data input
    • The arduino computes the raw coordinates to directional velocity using a set delay
    • Digital outputs of arduino lights up LEDs of the same color based on the magnitude of velocity


  • What would we do next:
    • Add foam casing and a safety strap to the toy to increase the safety factor of the toy and potentially lower its age group
    • Implement an adjustable tapers for children to explore the relationship between slit hole size and sound intensity for an older audience
    • We would try make the whistle out of wood and aluminum and see the difference material makes for sound


  • For teachers/parents:
    • Background knowledge of centripetal force is needed. The more force applied on the string to spin the whistle, the faster the whistle goes, and the louder the sound it makes. Also need additional knowledge of air compression and sound waves. The LEDs reinforce the learning
  • For children:
    • Explore swinging the whistle in multiple directions and orientation to see the difference in sound. Try blowing into the whistle and come up with theories of how slits affect the sound