To obtain the accurate position of the disordered and obscured workpieces on the production line,and to support the subsequent gripping of specific parts of the workpieces by the robot arm,a high precision 3 D laser scanner is used to scan the disordered workpieces on the production line in this paper.The Voxel down sampling,plane segmentation and DBSCAN clustering methods are applied to the original point cloud to segment the individual workpiece point clouds.Then,the coarse registration algorithm of k 4 PCS and the precise registration method of the GICP based on accelerated kd trees are adopted to register the actual point cloud of the workpiece with the standard point cloud template(converted from the mechanical design drawing of the workpiece).Finally,the accurate posture transformation matrix between the two is obtained,and the accurate posture of the workpiece placement is obtained.In order to verify the effectiveness of the proposed method,the position and attitude determination experiment is carried out on three workpieces in different shapes in the production line.The results show that the proposed method has good solution accuracy(error≤3mm)for different shapes of workpiece placement.