Design And Kinematics Research Of Pneumatic Soft Arm

The traditional rigid robot is difficult to adapt to the complex working environment because of its lack of deformation ability and flexibility.The adaptive ability of soft robot is widely concerned.In this paper,the aerodynamic soft robot is studied and a modular aerodynamic soft arm with taper is designed.The details are as follows:In this paper,the soft manipulator with integral taper is presented,the braided wires are wound externally,and the motion performance is optimized by integrating springs internally.Each module,the soft driver,is bent and extended in different directions by a different combination of air pressure in three identical chambers.Each module has 3 degrees of freedom,and the whole soft manipulator has 6 degrees of freedom.The whole design process is optimized by comparison of scheme and simulation.A complete set of mold for software driver is designed,and the whole manufacturing process and the problems needing attention are introduced.The simulation process of the driver is designed in the finite element analysis software.Specifically,an embedded method is proposed to solve the integration problem of braided wire and spring by means of aerodynamic fluid simulation,which simplifies the difficulty of simulation calculation.After that,a series of simulation designs of bending and stretching work are completed by inflating the chamber of the software driver.Finally,the whole workspace of the software driver is analyzed and the estimation is realized by using simulation post-processing.Based on the constitutive model of rubber and virtual work principle,the relationship between pressure and elongation and bending Angle of soft actuator is obtained.In the forward kinematics,the discrete constant curvature kinematics model based on taper is used to describe the attitude,and the attitude iteration of the whole soft arm is completed through the homogeneous transformation matrix.Monte Carlo method is used to study the workspace of two software driver modules.In the aspect of inverse kinematics,the inverse operation based on constant curvature formula and mathematical geometry method simplify the solution space of soft manipulator.Considering the weight of software driver,the algorithm of the model is optimized and verified by simulation.Finally,the experimental platform of the soft manipulator is built,and the rationality of the model is verified by bending and stretching experiments of the soft manipulator.The constant curvature model was verified by combined experiments of air pressure and the inverse kinematics process was verified by tracking the trajectory circle.Finally,it is shown that the designed aerodynamic soft manipulator has good working range and motion performance.