Modeling And Control Of Variable Stiffness Soft Manipulator Coupled With Jamming Mechanism And Pneumatic Driver

The soft robot has the characteristics of biological flexibility and important application value in the grabbing of fragile objects and irregularly shaped objects.Nevertheless,the precise control of soft robots is a difficult problem.Due to the nonlinear characteristics of soft robots and the uncertainty of the surrounding environment,it is difficult to establish an accurate kinematics model.There is currently no general control method.Therefore,the field of dynamic control of soft robots is a challenging field in its infancy.This paper presents a modeling and control method for a variable stiffness soft robot coupled with a jamming mechanism and a pneumatic driver.The details are as follows:Firstly,the structure of a variable stiffness soft robot coupled with a jamming mechanism and a pneumatic driver is researched.Then,the pneumatic control system which is required by the coupled variable stiffness soft robot is introduced in detail.In addition,the control scheme technical route of the adaptive control system is proposed.Secondly,the discrete element method(DEM)is used to analyze the jamming mechanism;the finite element method(FEM)is used to analyze the pneumatic actuator;the DEM-FEM method is used to comprehensively analyze the coupling effect.It is concluded that the main force key accounted for more than 90% and the optimal aspect ratio is evenly distributed.Therefore,the variable stiffness soft robot coupled with the jamming mechanism with good pressure transmission uniformity is obtained.Thirdly,the variable stiffness robot the segmented constant curvature method is used to model.The forward and inverse kinematics are used to analyze the motion process.At the same time,the visual control system was established and the adaptive control scheme whose stability was verified was used to compensate it.Finally,the simulation of adaptive control theory was completed.Finally,the production process of the jamming mechanism and the pneumatic software driver is introduced,and the production of the variable stiffness software robot is completed.At the same time,a rigidity test experimental platform and experimental environment were built,including the assembly of experimental equipment and the configuration of experimental equipment.Therefore,the stiffness test experiment and the bending performance experiment of the coupled variable stiffness soft robot have been completed which verifying the simulation analysis in Chapter 3.In addition,the adaptive ability of the soft robot is tested.Through adaptive control,the final x-axis coordinate accuracy is increased by 4.68%,and the y-axis coordinate accuracy is increased by2.60%,which verifies the effectiveness of the proposed adaptive control method.