Origami-Inspired Bistable SMA Microdevice

Abstract The ancient art of origami enables to create 3D shapes from a flat sheet of paper. This concept can be applied to a planar matrix composed of interconnected tiles, which can be self-folded and unfolded using actuated SMA bridges. Origami-inspired self-folding structures offer several advantages, including rapid in-plane fabrication, reduced assembly time, and lightweight designs with high rigidity. Previous research has primarily concentrated on macro-sized demonstrators that have proven advanced functionality in a variety of fields, including robotics and aerospace. In this work, we extend this concept to the microscale by creating a network of self-folding microactuators that can be programmed and controlled through local Joule heating. Our previous concepts faced limitations for reversible latching of tiles in their position after actuation. This paper presents the design, fabrication, and characterization of an origami-inspired bistable microdevices that utilize antagonistic SMA microactuators for bi-directional self- folding and heatable magnetic SMA films for reversible magnetic micro-latching.