Motion Control Of Lightweight Humanoid Robot Arm

Motion control of the robot arm is the key technology that determines its practicality.With the development of robot arms towards light,humanized and low cost.Achieving friendly motion control of a lightweight humanoid robotic arm has become a hot and difficult point of current research.In this paper,a lightweight humanoid robotic arm prototype called LWH-Arm and motion control platform are established independently.From the theoretical research,algorithm design,simulation verification and prototype control,the motion control strategies of a lightweight humanoid robotic arm are studied.Firstly,analyze the physical and motion characteristics of the human arm,then,the simulation and physical prototype model of LWH-Arm with weight of 3.45 kg,length of 81 cm,load of 500 g and 8 degrees of freedom(including 1 degree of freedom of the end gripper)are designed;Analyze the rotation and translation relationship between each joint of LWH-Arm.The kinematics model of LWH-Arm is established by D-H parameter method in Mat Lab,then,the forward and inverse kinematics equations and joint workspaces are calculated and verified to provide movement data for LWH-Arm prototype control.Secondly,combine the motion mode and the constraints of LWH-Arm,using cubic and quintic polynomial interpolation planning algorithms on joint space,line and arc interpolation planning algorithms on Cartesian space to plan the motion trajectory of LWH-Arm.Then,simulate and verify the planning algorithm in Mat Lab.The movement flexibility and stability of LWH-Arm are improved.Then,analyze the driving principle of the steering gear.Design independent joint and multi-joint cooperative drive control algorithm to realize the debugging and cooperative motion control of LWH-Arm joints.Design a radial zero torque extension shaft for Steering gear,to solve the problem that the steering gear is blocked due to the radial torque caused by the rotary shaft and the mechanical deformation,Design and combine the software and hardware system to realize the human-machine interactive control of LWH-Arm.Finally,design the experimental scenes to evaluate the flexibility,stability and load capacity of the LWH-Arm movement.The experimental results are as follows:(1)Collecting the movement data of hand rising of human arm through Kinect,to drive LWH-Arm simulation model and prototype to move.Implementation of humanoid actions and the movement flexibility of LWH-Arm were verified.(2)Through drinking water experiments,the stability of LWH-Arm movement is verified;it's load capacity up to 500 g and has the ability to do light household chores.The completion of the experiments show that the motion control scheme designed for LWH-Arm in this paper is feasible and effective.