4D Thermomechanical metamaterials for soft microrobotics

Abstract Metamaterials have attracted wide scientific interest to break fundamental bounds on materials properties. Recently, the field has been extending coupled physical phenomena where one physics acts as driving force for another. Stimuli-responsive or 4D metamaterials demonstrated thermo-elasticity, magneto-optics piezo-electricity. Herein, a soft, ultra-compact and accurate microrobot is described which can achieve controlled motion under thermal stimuli. The system consists of an organized assembly two functional structures: rotational translational element. Both elements are designed basing upon principle thermoelastic bilayer plate that bends temperature changes. Samples fabricated using gray-tone lithography from single polymer but with different laser writing powers, making each part in its mechanical behaviors. Excellent motion-controllable, reversible stable features dry environment verified by simulations experiments, revealing broad application prospects soft micro actuators.