Reprogrammable and bistable magnetically driven pixel array with customizable surface properties

Programmable functional surfaces face a tradeoff between fast reprogrammability and stable self-maintainability. The integration of field-responsive materials offers convenience for repeated programming of functional surfaces but necessitates continuous energy input to maintain the programmed functions. Meanwhile, technologies such as shape memory and functional coatings enable stable maintenance of surface states but result in a time-consuming reprogramming process. This tradeoff limits the demonstration of surface properties. We present a magnetic mini flap (at the millimeter scale) that can self-maintain its surface state and a pulsed magnetic tip to enable local fast reprogramming of the mini flaps within 100 ms. The mini flaps are arranged in a pixel array, where each pixel can be customized for specific surface properties, such as wettability and reflectivity.