Modeling and Analysis the Bending Behavior of Soft Pneumatic Network Actuator with Hyperelastic Models

Soft robots made of hyperelastic materials are widely used in transportation and medicine. Analyzing the behavior of soft actuators is a challenging process due to the nonlinear nature of hyperelastic materials. This article examines the effect of geometrical parameters such as the thickness of the walls, the distance between the chambers, the layers thickness, the side walls thickness, shape of cross section and selecting the material in the construction of the actuator on the bending behavior, the created stresses in the inner walls and the resulting tip force of the actuator to obtain the optimal geometry and the best material with the aim of creating the maximum bending angle and the maximum tip force of the actuator. For accurate modeling the material behavior of soft actuator construction material such as: DS30, TPU, EF30 and RTV2, the predictions of 5 Hyperelastic models Neo-Hookean, Yeoh3 parameters, Ogden1, Ogden2 and Moony-Rivlin are compared with stress-strain curves are obtained from uniaxial tensile test on these materials and the best model is selected to modeling of each material. The results show that, by reducing the thickness of the walls, the distance between the chambers, the thickness of the lower layers and using the square cross section and RTV2, the actuator maximum bending angle is obtained. Also, by increasing the thickness of the walls, the