气动软体机械臂模块变刚度性能分析

For solving the defect of insufficient structural stiffness in soft manipulator, a module of pneumatic soft manipulator is designed according to the characteristics of currently soft manipulator. The module is designed by variable stiffness principle of coupling and consist of two connecting plates at the upper and lower ends, bending chambers between in the two plates and variable stiffness chamber in the middle. It can realize modularity, stiffness adjustment and load capacity in this continuum soft manipulator. Based on the hyperelastic material characteristics of silicone, a non-linear mechanical model suitable for pneumatic soft manipulator is established for analyzing the variable stiffness. Combining with the torques of the chambers and actual bending process of the module, this paper designed a static tensile test for evaluating the performance of variable stiffness chamber by applying redundant driving moment. Through the experiment and demonstration, the mapping relation between the inflatable pressure and the stiffness of the module is obtained, which provides the mechanical theory support for the stiffness calculation of the pneumatic soft manipulator and the practical application of the module.