Actuatable Flexible Large Structure Using a Laminated Foam-based Soft Actuator

Recently, various types of soft actuators and their applications have been studied in the search for alternatives to conventional robots. In particular, pneumatic soft actuators have the advantages of a light weight and high power. One of the applications of such soft actuators is fusion with flexible structures. However, because these actuatable flexible structures consist of rubber, silicone, or flexible resin, it is difficult for them to support their own weight, owing to the effect of the square-cube law in the case of an increasing size. We have developed actuatable flexible structures. LayerCAKE is a laminated open-cell and closed-cell foam structure, where cell foam is a lightweight and flexible material that can be used to realize large actuatable flexible structures. LayerCAKE is actuated using the concept that open- and closed-cell foams contract differently when they are vacuumed. In this paper, the design of a large LayerCAKE mechanism is described and tested. A large actuatable flexible structure of size approximately 1250 mm that bends in a vertical direction was realized.