Analysis modeling and experiment of bionic winding soft actuator inspired by plant tendrils

Abstract

As a special group of plants, vine plants can be spontaneously fixed with supports by winding or adsorbing. If the vine winding behavior is combined with a soft actuator, it is expected to improve the performance of the soft actuator in unstructured environments. Based on the pneumatic network structure, this study proposes a soft actuator with a symmetrical chamber and capable of winding or bending motion by imitating the winding motion of vine plants. Through the coupling motion of the symmetrical chamber under different or the same pressures, the winding flexibility of imitating vine plants can be better realized. Based on the minimum potential energy method and the constant curvature assumption, combined with the Yeoh model for large deformation of super elastic body, the deformation trajectory model of soft actuator in two states of unilateral winding and bending is constructed. The influence of structural design parameters of soft actuator on winding deformation is analyzed by finite element analysis. Finally, the reliability of the theoretical mathematical model is verified by experiments, the working performance of the software driver is tested, and the possible future applications are demonstrated.