Research
The vibrating ruler pushes the molecules in the air, making them bunch together. As the ruler vibrates back and forth it makes waves of molecules pushed together (pressure waves). The molecules transmit these pressure waves through the air into our ear, where they are converted to electrical signals that get sent to our brain.
When the ruler is longer it vibrates more slowly, so pushes molecules together less often, so the waves of molecules are further apart – the frequency of sound waves are lower. Lower frequency waves have a lower pitch.
When the ruler is shorter it vibrates more quickly, so makes higher frequency pressure waves, which have a higher pitch.
http://www.ingridscience.ca/node/497
Experiment
(video – varying width & thickness)
(video – varying length)
IDEATION
Deriving the concept of how different lengths and thickness of material can produce sounds in different notes, I picked soft wood as my main material.
The point of using only 1 material, is to highlight on how simply by varying the certain conditions of the same material, it can produce sounds of different notes and layers! 🙂
Another material used is the marble. It is interesting as it creates a special sound together with the soft wood.Â
Inspirations
An enveloped structure (similar to 20 sided dice/ virus cell wall)
Ms Cheryl’s chicken feeding toy
Chinese yo-yo
Egg Shaker
Process
Creating unique pieces in varying sizes (length & thickness) and then assembling each of them together. They must be closely pieced so that the marble would not fall out! 
Finally trimming pieces and adding the marble in, before sealing the piece. Would be horrible news if I forgot to put the marble and sealed it first…Â
The original idea ended here, but EUREKA. The sound invoked an idea – chinese yoyo!
The sticks and strings were then added to include entertainment value to the piece.
TADA my finishing piece!Â