Magneto-active soft matter with reprogrammable shape-morphing and self-sensing capabilities

Interest in creating soft active matter that can repeatedly undergo shape morphing and self-sensing in response to external stimuli is growing. Magneto-active soft matter (MASM) with untethered, fast, and reversible shape reconfiguration is highly desirable for diverse applications in biomedical devices , wearable devices , soft robotics. In this work, we develop a heat-assisted magnetic reprogramming strategy for fabricating MASMs capable of reprogrammable shape-morphing and self-sensing functions. The magnetic reprogramming strategy is based on heating thermoplastic matrix above its melting point and reorienting soft-magnetic particle chains by applying magnetic fields during cooling. By reprogramming magnetization profiles through particle chain reconstruction of printed architecture, we demonstrate multiple deformation modes with distinct shape-morphing. This magnetic reprogramming approach enabled multiscale and reprogrammable soft machines with the tunable actuation response, such as adaptive grasping of a soft gripper. In addition, in combining with the unique sensing mechanism of triboelectric skin (tribo-skin), the self-sensing performance of MASMs is realized by using electrical signals to identify the deformation and contact behaviors. We anticipate that the magnetic reprogramming strategy and multimaterial 3D printing-assisted technique can open new avenues for the fabrication of multifunctional MASMs.