3D位姿估计结合阻抗控制的沉孔装配  

Assembly of countersunk-hole parts based on 3D pose estimation and impedance control

作　　者：陈平[1] 雷学军 李灿[1] 胡义亮 陈爽[1] CHEN Ping;LEI Xuejun;LI Can;HU Yiliang;CHEN Shuang(College of Mechanical and Vehicle Engineering,Chongqing University,Chongqing 400044,China)

机构地区：[1]重庆大学机械与运载工程学院,重庆400044

出　　处：《光学精密工程》2022年第22期2889-2900,共12页Optics and Precision Engineering

基　　金：国家重点研发计划资助项目(No.2019YFB1703600)。

摘　　要：面向长圆轴零件与沉孔零件的自动装配需求,针对装配中任意位置和姿态的零件柔顺装配的问题,研究了3D视觉和力觉结合的柔顺装配策略。在3D视觉定位方法中,提出了一种沉孔零件位姿估计的算法:首先使用超体素分割和约束平面分割(Constrained Planar Cuts,CPC)聚类完成点云数据的预处理,再利用基于权重的随机采样一致性(Weightbased Random Sample Consensus,WRANSAC)平面拟合完成平面定位,通过沉孔的轮廓提取与圆拟合估计装配位置。在力觉方法中,采用阻抗控制实现零件的柔顺装配。实验结果表明:本文提出的WRANSAC平面拟合算法的平均距离误差Δd可以达到0.09 mm,角度误差Δθ可以达到1.8°;3D空间中沉孔位姿的角度误差为1.0°,可实现配合间隙为0.5 mm的零件的装配。装配策略满足沉孔装配对精度及柔顺的要求。For robotic assembly long cylindrical shaft and countersunk-hole parts,this paper investigates the assembly strategies of combining 3D vision,and force perception for compliantly assembling parts in arbitrary positions and poses during assembly.An algorithm is proposed based 3D vision for pose estimation of countersunk-hole parts:firstly,use supervoxel segmentation,Constrained Planar Cuts(CPC)and clustering to complete the preprocessing of point cloud,and then use Weight-based Random Sample Consensus(WRANSAC)plane fitting to acquire plane pose,finally,estimate the assembly position by profile extraction and circle fitting of countersunk-hole.In addition,we implement the compliant assembly of the parts using impedance control.The experimental results indicate that the average distance errorΔd of WRANSAC plane fitting algorithm can be as high as 0.09 mm and the angular errorΔθcan be as high as 1.8°.Moreover,the angular error of the countersunk-hole position in 3D space is 1.0°,which can realize the assembly of parts with a mating clearance of 0.5 mm.The assembly strategy meets the requirements of high precision and compliance of countersunk-hole assembly.

关 键 词：沉孔零件 柔顺装配 3D位姿估计 阻抗控制 

分 类 号：TP394.1[自动化与计算机技术—计算机应用技术] TH691.9[自动化与计算机技术—计算机科学与技术]