Arduino + Firefly + Grasshopper

Hello I am an architecture student working on the design of a patterned wall whose individual patterns (circles or diamonds or what have you) will rotate about central axis when a user's presence is detected. For my project I need to produce a prototype which shows that the technology works and is possible. (i.e wave hand in front of a panel and it rotates).

I have just purchased the Arduino Uno Starter Kit and have the plug-in 'Firefly' for Grasshopper which I will be using to program the inputs etc for the sensor. I was wondering if anyone had any advice to ensure success?

I am very new to using this type of technology and would like to know what kind of materials would be best to create a mechanism of sorts which would cause a panel to rotate when Arduino senses a user? I have found examples of SMA wires which could be used, but these require heat to cause shrinking (which could be designed to create a rotating effect I suppose?)

Any ideas and advice would be greatly appreciated! I am really invested in this project and have six weeks from now to make it work :D

Best,

Matt