Scientists from Columbia, Harvard and MIT have collaborated to create a xylophone-like instrument that has keys shaped like animals. It's not just a cute toy, however. Their "zoolophone" was designed using new technology that allows objects of a specified shape to produce a specified sound. It could ultimately be used to build things like low-noise computer fans, or bridges that don't amplify road noise.
The zoolophone is actually part of larger group of musical instruments known as metallophones.
These are devices – such as xylophones – that create sounds via vibrations within the instrument itself, as opposed to within parts of it, such as strings or reeds. Ordinarily, metallophones are made of uniformly-shaped components such as rectangular bars, the vibrational qualities of which are already understood. Builders of such instruments know, for instance, that adding a given number of dimples to the underside of one of the bars will affect its tone in a given way.
However, what if you wanted to make a metallophone in which each key had a very different shape, yet that still produced the same tones as a plain ol' xylophone? Well, that's what the zoolophone is.
To build it, the scientists created an algorithm in which users first indicate the planned building material, the desired shape, and the note (i.e: the frequency and amplitude) that they wish the key to produce when struck with a mallet. The program then subtly deforms and adds perforations to the shape, until it will be able to produce the desired sound while still maintaining the basic specified shape. It can then be 3D-printed or milled.
"Acoustic design of objects today remains slow and expensive," says Columbia's Prof. Changxi Zheng, who led the research. "We would like to explore computational design algorithms to improve the process for better controlling an object’s acoustic properties, whether to achieve desired sound spectra or to reduce undesired noise. This project underscores our first step toward this exciting direction in helping us design objects in a new way."
A paper on the zoolophone is being presented this week at the SIGGRAPH Asia conference, in Japan. The instrument can be seen and heard, in the video below.
Source: Columbia University