Research On 3D Reconstruction And Motion Planning Of 6-DOF Robot Workspace

The six-degree-of-freedom robot assembly technology is a cutting-edge technology with broad application prospects.In the face of the customization of modern manufacturing models,the characteristics of small batches and the diversified needs of the market,the traditional teaching-type industrial robot assembly can no longer adapt to this complexity.The unknown assembly environment requires the realization of robot intelligent assembly and collaborative assembly,giving robots the integrated functions of perception,decision-making,and execution.This article will take the six-degree-of-freedom operation robot shaft assembly as the research object,based on the monocular camera and depth camera sensor,from the construction and calibration of the environment-aware vision system,the camera pose estimation and three-dimensional reconstruction based on the environment-aware vision system,and the six-freedom The research is carried out in three aspects of the motion planning of the operation robot.1.The construction and calibration of the environmental perception visual system.First of all,aiming at the assembly of such scenes in the shaft hole of the semi-enclosed space,the Kinect v2 PTZ vision system and the EIH(Eye-in-Hand)monocular vision system are combined to build the environment perception vision system;Secondly,the two vision systems are carried out Calibrate,get the transformation matrix of Kinect v2 camera coordinate system relative to the robot base coordinate system,and monocular camera relative to the sixth-axis coordinate system of the six-degree-of-freedom operation robot;Finally,calibrate the Kinect v2 camera and the monocular camera sensor,The results show that the relative error in the direction of the transformation matrix of the Kinect v2 camera's color lens to the infrared lens is 0.53%,and the average relative error of the internal parameters of the monocular camera is 1.66%.2.Three-dimensional reconstruction of visual system based on environment perception.The method in this chapter is as follows:the three-dimensional reconstruction method is applied to such scenes as the shaft hole assembly inside the semi-enclosed space to provide the robot with the three-dimensional pose information of the obstacle and the assembly target.First,based on the SLAM(Simultaneous Localization And Mapping)framework and Kinect v2 PTZ vision system,complete the construction of the external 3D point cloud in the semi-enclosed space;Secondly,the monocular vision SLAM algorithm and the SFM(Structure From Motion)algorithm are combined.Solve the problem that the depth camera cannot enter the semi-enclosed narrow space,complete the positioning of the monocular camera,avoid the robot from colliding with the internal environment of the semi-enclosed space,and complete the construction of the three-dimensional point cloud inside the semi-enclosed space;Finally,pass Experiments verify that the 3D reconstruction method in this paper is feasible and effective.3.Research on the motion planning algorithm of the six-degree-of-freedom manipulating robot.The proposed method is as follows:First,based on the behavioral dynamics theory,the robot end effector position and attitude dynamics model is established,and the speed term in the model is improved.The simulation comparison results show that the improved speed can be adaptively changed.Smoother;Secondly,set fixed control points and floating control points on the robot joints and connecting rods to ensure that the connecting rods and joints do not collide with obstacles;Finally,the behavioral dynamics model and the collision detection algorithm are fused,simulation and experimentation.The results show that the motion planning method proposed in this paper can generate a collision-free path when the initial pose and target pose are given,and the end effector speed adaptive change is realized.4.Simulate the shaft hole assembly experiment in a semi-enclosed space.First,use the calibration results and 3D reconstruction results of the environment-aware vision system to complete the coordinate conversion,and obtain the pose conversion matrix of the local target point outside the simulated semi-closed space and the center point of the target hole relative to the robot base frame;Secondly,design the experimental plan,build an experimental platform that simulates the shaft hole assembly in the semi-enclosed space;Finally,use the six-degree-of-freedom operation robot motion planning algorithm proposed in this paper to complete the shaft hole assembly experiment in the semi-enclosed space.