Three-finger Underactuated Rigid-flexible Hybrid Manipulator

With the development of modern industry towards automation and intelligence,people’s demand for robot technology is also growing,manipulator as the end-effector of robot plays an important role.At present,the fully driven manipulator has higher flexibility and more comprehensive functions,but its control is complicated,cost is expensive and practical application is less.The underactuated manipulator has stable grasping performance,simple control and low cost,which has good research value.The traditional underactuated rigid manipulator has poor flexibility and high control precision,while the flexible soft manipulator has small stiffness and weak load capacity,which reflects the limitations of the two manipulators.Therefore,according to the characteristics of the above different types of manipulators,combined with their advantages,a three-finger underactuated rigid-flexible hybrid manipulator is designed,and based on its kinematics analysis,the grasping mode and grasping ability are simulated and tested.The functional requirements of the manipulator are analyzed and the basic configuration of the manipulator is determined.The overall design scheme is proposed,the finger structure and overall layout are designed,and the key components are selected and analyzed.Using the finger transposition mechanism,various grasping modes are determined for different objects.According to the design of the manipulator structure,the finger kinematics and static mechanics analysis,using Denavit-Hartenberg method to get the coordinates of the end of the finger,and MATLAB kinematics simulation software,get the trajectory and movement space of each finger,and the rationality of the manipulator workspace was verified.The mechanical model of the finger was established,and Abaqus finite element software was used to analyze the elastic joint material,and the influence of different section characteristics on finger buckling was obtained.Six kinds of grasp modes are designed according to the grasp mode and the characteristics of finger rotation mechanism.Virtual prototype is built in Adams software,and the typical grasp mode is simulated and analyzed,so as to verify the feasibility of grasp planning.3D printing technology was used to produce the manipulator prototype,and the experimental platform was built.Different grasping modes were used to grab objects,and the grasping performance was tested and verified.Compared with the rigid manipulator,the grasping stability and adaptability of the manipulator are tested.The experimental results show that the rigid-flexible hybrid manipulator has good grasping performance,that can carry out adaptive grasping of objects through different grasping modes,with good stability and achieve the desired effect.