A systematically derived design for a modular pneumatic soft bending actuator

In the field of pneumatic soft robots, arranging three air chambers in parallel is a common technique in order to build a bending actuator. Although these three chamber actuators are often used, many designs are based on trial and error, rather than on systematic investigation. In this study, we present a novel modular three chamber bending actuator. We derive beneficial design parameters from a systematic investigation that targets not only bending performance but also ease of fabrication and modeling. Due to its modularity, the bending actuator can be used as a “construction kit”, i.e. a customized actuator can be build by combination of basic components. Furthermore, individual components of the actuator can be reused in another configuration, if desired. The characteristics of the actuator are identified experimentally. Its maximum bending and stretching is satisfying, but lower than that of the well-known “STIFF-FLOP” due to the reinforcement that was chosen to reduce the manufacturing effort.