Reconfigurable magnetic origami actuators with on-board sensing for guided assembly

Origami utilizes orchestrated transformation of soft two-dimensional structures into complex three-dimensional architectures, mimicking shapes and functions found in nature. In contrast to origami in nature, synthetic origami lacks the ability to monitor the environment and correspondingly adjust its behavior. Here, we design, fabricate, and demonstrate magnetic origami actuators with capabilities to sense their orientation and displacement and detect their own magnetization state and readiness for supervised folding. These origami actuators integrate photothermal heating and magnetic actuation by using composite thin films (~60 µm thick) of shape-memory polymers with embedded magnetic NdFeB microparticles. Mechanically compliant magnetic field sensors, known as magnetosensitive electronic skins, are laminated on the surface of the soft actuators. These ultrathin actuators accomplish sequential folding and recovery, with hinge locations programmed on the fly. Endowing mechanically active smart materials with cognition is an important step toward realizing intelligent, stimuli-responsive structures.