A Static Modeling Approach for Thin-Walled Soft Robotic Arms Considering Geometric and Material Nonlinearity

The current design based on air chambers makes thin wall a typical feature of soft robotic arms. Considering this characteristic, a new static modeling method that integrates the principle of virtual work and a spring-fluid equivalent modeling idea is proposed in this work. The method is able to consider both geometric and material nonlinearity of the soft robotic arm. A general physical model of the thin-walled soft robotic arm and the static modeling process are presented. Then, an experimental prototype of the thin-walled soft robotic arm is fabricated and the experimental verification of the proposed method is carried out. The comparisons between the theoretical prediction and experimental results under different load conditions illustrate that the proposed static modeling method can be used to describe the static deformation of soft robotic arms with high accuracy. The proposed static modeling method provides a new way to model the soft robotic arm and has guiding significance for the design of soft robotic arms.