Fluctuations

Fluctuations is a system that represents 3D surfaces in space. To create these surfaces, balls are used to show the points on the plain. These spheres hang on cables which are connected to stepper motors (motors that control with great precision the angle of rotation). The stepper motors are controlled through a computer to change the altitude of each ball, creating the surface that is desired.

Check this on the wiki fluctuations

 

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