Research And Design Of Man-machine Combined Upper Limb Assisted Mechanical Arm

In the field of loading and unloading of machine tools,the handling of small materials within 10 kg is mainly done by the workers.Long-term work can cause fatigue of the upper limbs.In addition,the improper operation of the machine tool or the occurrence of unexpected situations may also cause damage to the upper limbs of the human body.To solve the above problems,a wearable power-assisted robot arm based on hydraulic drive is designed in this paper.By wearing the power-assisted arm,the end load force is transmitted to the whole body,thus alleviating the fatigue of the upper limbs.At the same time,the end-effector replaces the worker's manual operation which plays a safety protection role.The main research work are as follows:Structural design.According to the working requirements,a 5-DOF assisting robotic arm was designed from the mechansm of human upper limb movement;The driving method is hydraulic drive,and the hydraulic circuit is analyzed and designed;The transmission mode is wire rope transmission,and the wire rope is selected;The finite element analysis of the robotic arm is performed to verify the reliability of the structural design.Kinematic analysis.The kinematics model was established by D-H method to calculate the forward and inverse kinematics solutions.Based on the Monte Carlo algorithm,drawing workspace by Matlab;The mapping relationship between joint speed and end effector speed is established by solving the Jacobian matrix;Based on ADAMS to kinematics simulation analysis for two common handling tasks.Kinetic analysis.The gravity balance model is established by adding auxiliary springs and pulleys to keep the potential energy unchanged and reduce the joint loss;The Lagrangian equation is used to establish the dynamic equation.Using ADAMS for dynamic simulation to obtain the joint torque curve under gravity equilibrium and non-gravity equilibrium to examine the effectiveness of gravity balance.