Self-folding of polymer sheets using local light absorption
by Skylar Tibbits & Vernelle A. A. Noel,
Shrinky-Dink, Heat Lamps, Black Ink
transparent, pre-strained polystyrene sheets (also known as Shrinky-Dink) shrinks in-plane if heated uniformly. We used black ink Sharpies and patterned both sides of the polymer sheet. This provides localized absorption of light, which heats the underlying polymer above its glass transition. At these temperatures, the inked regions relax and shrink, causing the sheet to fold into a three-dimensional object.