Versatile and controllable shape morphing using twisted-and-coiled actuators

Various shape morphing strategies have been investigated in recent years. Even though existing work has demonstrated complicated shape morphing (e.g., a human face), they can only deform along with a predefined pattern. We propose a different strategy: strategically embedding soft actuators into a soft body to enable versatile shape morphing by actively controlling the deformation of each soft actuator. We utilize a soft actuator, twisted-and-coiled actuators (TCAs), which can be easily fabricated from low-cost sewing threads to generate large force and displacement. We also leverage a jamming-based method to change the stiffness of soft bodies. With these two elements, we realize a shape morphing module that can quickly transform to and hold versatile shapes to adapt to various environments. Different modules can also be combined to generate more complicated shapes. We demonstrate a fast grasping and holding process, which consumes no energy, with a gripper with two shape morphing fingers. We also demonstrate a morphing surface that can hold different 3D configurations. We envision that the concept can be applied to soft robots, medical robots, morphing structures, etc.