Research On Pneumatic Modular Soft Manipulator

As an important supplement to rigid robotic arm,soft robotic arm theoretically has unlimited degrees of freedom and can realize more flexible movement.It has broad application prospects in the field of man-machine collaboration,medical rehabilitation training,space and underwater exploration and other complex and changeable environments.This paper mainly studies the pneumatic soft manipulator,adopts the modular design,based on the constant curvature hypothesis,large deformation beam theory and D-H method to carry out the kinematic modeling analysis of the single-module soft manipulator and the two-module soft manipulator.A prototype was designed and manufactured to study the performance of the single-module and two-module soft robotic arm,and the application prospect of the soft robotic arm was tested and studied.The main research contents are as follows:Firstly,a pneumatic modular soft robot arm is proposed.Each unit adopts three symmetrical independent pneumatic grid cavities.After the three cavities are driven respectively,each soft robot arm module unit can realize axial elongation and spatial bending motion.Based on the Yeoh model,the ABAQUS finite element simulation software was used to analyze the influence of different parameters on the performance of the soft manipulator module.The appropriate structural parameters were selected according to the index results,and the simulation results and prototype production process were given.Secondly,based on the assumption of constant curvature and large deformation beam theory,the mathematical model describing the motion of the soft manipulator module is established,and the bending model and the elongation model are obtained.Considering the influence of gravity on the bending performance,the bending models of single and double module soft manipulator are modified.For a two-module soft manipulator in the same plane used for stable grasping,the improved bending model considering gravity is obtained.D-H method was used to analyze the forward and inverse kinematics of the soft manipulator,and the mapping relationship from the drive space to the configuration space and then to the operating space was obtained.Matlab software was used to simulate and analyze the motion space configuration of the single and twomodule soft manipulator,and the working space of the single and two-module soft manipulator under the combination of gravity and different working forms was solved.And do comparative analysis.Finally,the important hardware selection of the pneumatic control platform was completed,and an experimental platform was built to test the bending and elongation motion and mechanical properties of the soft manipulator module.The kinematic experiment of the two soft manipulator modules was carried out,and the experimental results,simulation results and theoretical model results were compared and verified by ABAQUS finite element software simulation.The experimental results show that the kinematic model results are similar to the simulation and experimental results when the charging pressure ranges from 0 to 80 k Pa.Based on the forward and inverse kinematic models established,the two-module soft manipulator was tested in the grasping test of fixed position and the obstacle-avoiding grasping test to verify its application prospect.