Stiffness Analysis and Error Compensation of Lunar Sampling Manipulator
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摘要:针对在月面采样任务中，表取采样机械臂受臂杆和关节柔性影响，呈现低刚度特性导致机械臂控制精度降低的问题，提出了一种基于机械臂柔性变形估计的末端操作误差补偿方法，通过分析关节柔性、臂杆柔性和自重等因素对机械臂末端位姿的联合影响关系，构建了多自由度机械臂的整体刚度模型，进一步通过有限元分析和真实变形比对等方法，对机械臂整体刚度模型的误差计算精度进行评估定界，给出了机械臂在不同构型条件下末端位置估计的误差边界。在此基础上设计了机械臂末端操作的一次性补偿控制方法，可将机械臂末端的最大控制偏差从35 mm降低到1 mm以内，极大提高了表取采样机械臂模拟系统的绝对定位精度。Abstract:In the lunar surface sampling mission, the lunar sampling manipulator is affected by the flexibility of the boom and joints, which presents low stiffness characteristics and leads to the reduction of robotic arm control accuracy. To address the above problems, this paper proposes an end-operation error compensation method based on the estimation of flexible deformation of the robotic arm, and constructs an overall stiffness model of the multi-degree-of-freedom robotic arm by analyzing the joint flexibility, arm rod flexibility and self-weight and other factors on the joint flexibility of the end position of the robotic arm. The error bounds for the end position estimation of the robot arm under different configuration conditions are given. On this basis, a one-time compensation control method for the end operation of the robotic arm is designed, which can reduce the maximum control deviation of the end of the robotic arm from 35 mm to within 1 mm and greatly improve the absolute positioning accuracy of the lunar sampling manipulator simulation system.Highlights
● The effects of joint flexibility, arm bar flexibility and robot arm self-weight on the end error of the lunar sampling manipulator were analyzed. ● The stiffness model of the lunar sampling manipulator for table sampling is established. ● A stiffness model-based error compensation method for the lunar sampling manipulator. is proposed. ● The proposed method solves the problem of control accuracy degradation caused by flexible deformation of the lunar sampling manipulator. -
表 1表取采样机械臂DH参数表
Table 1Table of DH parameters of table mining robot arm
$ i $ ${\theta }_{i}/(^{\circ})$ $ {d}_{i}/\mathrm{m}\mathrm{m} $ $ {a}_{i-1}/\mathrm{m}\mathrm{m} $ ${\alpha }_{i-1}/(^{\circ})$ 1 $ {\theta }_{1} $ $ {d}_{1} $ $ 0 $ $ 0 $ 2 $ {\theta }_{2} $ $ {-d}_{2} $ $ 0 $ $ -pi/2 $ 3 $ {\theta }_{3} $ $ {-d}_{3} $ $ {a}_{2} $ $ 0 $ 4 $ {\theta }_{4} $ $ -{d}_{4} $ $ {a}_{3} $ $ 0 $ 
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表 25组仿真构型
Table 2Five groups of simulated configurations
位姿 关节2/rad 关节3/rad 采样构型 0 1.571 –0.262 1.571 放罐构型 –1.571 1.571 –1.571 2.094 水平构型 0 0 下载:
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表 3理论建模和有限元的变形结果对比
Table 3Comparison of deformation results of theoretical modeling and finite elements
方法 构型 采样构型 放罐构型 水平构型 有限元/mm 2.350 3.548 3.337 2.575 9.885 理论法/mm 2.558 3.419 3.276 2.320 9.196 误差/% 8.8 3.6 1.8 9.9 6.9 下载:
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表 4表取采样机械臂参数
Table 4Part parameters
部件 质量/kg 长度/mm 上臂 2.57 1 450 下臂 1.77 1 300 关节2 8.48 — 关节3 2.80 — 关节4+执行器 2.83 — 下载:
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表 5真实机械臂测量实验构型
Table 5Experimental configurations of real robotic arm measurements
位姿 关节2/rad 关节3/rad 1 –0.524 2.094 2 –0.785 2.094 3 0 1.571 4 –0.262 1.571 5 0 1.047 6 0 0.785 7 0 0 8 –0.471 2.094 9 –1.571 2.618 10 –1.571 2.094 下载:
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[1] 叶培建,于登云,孙泽洲,等. 中国月球探测器的成就与展望[J]. 深空探测学报(中英文),2016,3(4):323-333.YE P J,YU D Y,SUN Z Z,et al. Achievements and prospects of Chinese lunar probes[J]. Journal of Deep Space Exploration,2016,3(4):323-333. [2] 张宽, 于天一, 胡晓东, 等. 月面表层无人采样控制技术[J]. 深空探测学报（中英文）, 2022, 9（2）: 173-182.ZHANG K, YU T Y, HU X D, et al. Control technology for unmanned sampling of lunar surface [J]. Journal of Deep Space Exploration , 2022, 9（2）: 173-182. [3] 韩亮亮,陈萌,张崇峰,等. 月面服务机器人研究进展及发展设想[J]. 载人航天,2018,24(3):313-320.doi:10.3969/j.issn.1674-5825.2018.03.005HAN L L,CHEN M,ZHANG C F,et al. Research progress and development conception of lunar service robot[J]. Manned Spaceflight,2018,24(3):313-320.doi:10.3969/j.issn.1674-5825.2018.03.005 [4] 马如奇,姜水清,刘宾,等. 月球采样机械臂系统设计及试验验证[J]. 宇航学报,2018,39(12):1315-1322.doi:10.3873/j.issn.1000-1328.2018.12.001MA R Q,JIANG S Q,LIU B,et al. Design and verification of a lunar sampling manipulator system[J]. Journal of Astronautics,2018,39(12):1315-1322.doi:10.3873/j.issn.1000-1328.2018.12.001 [5] 杨成,李贵良,冯晓萌,等. 月面采样机械臂遥操作仿真验证技术[J]. 中国科学:技术科学,2021,51(12):1480-1491.YANG C,LI G L,FENG X M,et al. Simulation and verification technology for lunar sampling manipulator control[J]. China Science:Technical Science,2021,51(12):1480-1491. [6] 胡晓东,张宽,谢圆,等. “嫦娥五号”月面采样机械臂路径规划[J]. 深空探测学报(中英文),2021,8(6):564-571.HU X D,ZHANG K,XIE Y,et al. Path planning of lunar surface sampling manipulator for Chang’E-5 mission[J]. Journal of Deep Space Exploration ,2021,8(6):564-571. [7] 吴锦辉,陶友瑞. 工业机器人定位精度可靠性研究现状综述[J]. 中国机械工程,2020,31(18):2180-2188.doi:10.3969/j.issn.1004-132X.2020.18.005WU J H,TAO Y R. Review on research status of positioning accuracy reliability of industrial robots[J]. China Mechanical Engineering,2020,31(18):2180-2188.doi:10.3969/j.issn.1004-132X.2020.18.005 [8] BRUNETE A,GAMBAO E,KOSKINEN J,et al. Hard material small-batch industrial machining robot[J]. Robotics and Computer-Integrated Manufacturing,2018,54:185-199.doi:10.1016/j.rcim.2017.11.004 [9] LIAN B,SUN T,SONG Y,et al. Stiffness analysis and experiment of a novel 5-DoF parallel kinematic machine considering gravitational effects[J]. International Journal of Machine Tools and Manufacture,2015,95:82-96.doi:10.1016/j.ijmachtools.2015.04.012 [10] ALICI G,SHIRINZADEH B. Enhanced stiffness modeling,identification and characterization for robot manipulators[J]. IEEE transactions on robotics,2005,21(4):554-564.doi:10.1109/TRO.2004.842347 [11] SPONG M W. Modeling and control of elastic joint robots[J]. Journal of Dynamic Systems,Measurement,and Control,1987,109(4):310-318. [12] SALISBURY J K. Active stiffness control of a manipulator in cartesian coordinates[C]//Proceedings of the 19th IEEE conference on decision and control including the symposium on adaptive processes. [S. l. ]: IEEE, 1980: 95-100. [13] CHEN S F,KAO I. Conservative congruence transformation for joint and cartesian stiffness matrices of robotic hands and fingers[J]. International Journal of Robotics Research,2000,19(9):835-847.doi:10.1177/02783640022067201 [14] KLIMCHIK A,FURET B,CARO S,et al. Identification of the manipulator stiffness model parameters in industrial environment[J]. Mechanism and Machine Theory,2015,90:1-22.doi:10.1016/j.mechmachtheory.2015.03.002 [15] WANG X,ZHANG D,ZHAO C,et al. Optimal design of lightweight serial robots by integrating topology optimization and parametric system optimization[J]. Mechanism and Machine Theory,2019,132:48-65.doi:10.1016/j.mechmachtheory.2018.10.015 [16] XU P,YAO X,LIU S,et al. Stiffness modeling of an industrial robot with a gravity compensator considering link weights[J]. Mechanism and Machine Theory,2021,161:104331.doi:10.1016/j.mechmachtheory.2021.104331 [17] 唐玲,梁常春,王耀兵,等. 基于柔性补偿的行星表面采样机械臂控制策略研究[J]. 机械工程学报,2017,53(11):97-103.doi:10.3901/JME.2017.11.097TANG L,LIANG C C,WANG Y B,et al. Research on flexible compensation control strategy for planetary surface sampling manipulator[J]. Journal of Mechanical Engineering,2017,53(11):97-103.doi:10.3901/JME.2017.11.097 [18] 刘志,赵正大,谢颖,等. 考虑结构变形的机器人运动学标定及补偿[J]. 机器人,2015,37(3):376-384.doi:10.13973/j.cnki.robot.2015.0376LIU Z,ZHAO Z D,XIE Y,et al. Kinematic calibration and compensation for a robot with structural deformation[J]. Robotics,2015,37(3):376-384.doi:10.13973/j.cnki.robot.2015.0376 [19] 陈钢,孙丰磊,李彤,等. 考虑弹性变形的月面表取机械臂精度补偿方法[J]. 南京航空航天大学学报,2021,53(1):1-10.doi:10.16356/j.1005-2615.2021.01.001CHEN G,SUN F L,LI T. Accuracy compensation for a lunar sampling manipulator with elastic deformation[J]. Journal of Nanjing University of Aeronautics and Astronautics,2021,53(1):1-10.doi:10.16356/j.1005-2615.2021.01.001 [20] 熊有伦, 李文龙, 等. 机器人学: 建模、控制与视觉[M]. 武汉: 华中科技大学出版社, 2018: 135-162. [21] 林义忠,廖小平,曾剑. 6R 喷涂机器人操作臂末端刚度的分析[J]. 广西大学学报:自然科学版,2011,36(2):234-240.LIN Y Z,LIAO X P,ZENG J. Analysis of arm end stiffness for a 6R-spraying robot[J]. Journal of Guangxi University:Natural Science Edition,2011,36(2):234-240. [22] DUMAS C,CARO S,GARNIER S,et al. Joint stiffness identification of six-revolute industrial serial robots[J]. Robotics and Computer-Integrated Manufacturing,2011,27(4):881-888.doi:10.1016/j.rcim.2011.02.003 [23] 高鹏宇. 打捞机器人误差补偿方法研究[D]. 哈尔滨: 哈尔滨工业学, 2020.GAO P Y. Research on error compensation method of the salvage robot [D]. Harbin: Harbin Institute of Technology, 2020. [24] 张永贵,刘文洲,高金刚. 切削加工机器人刚度模型研究[J]. 农业机械学报,2014(8):321-327.doi:10.6041/j.issn.1000-1298.2014.08.051ZHANG Y G,LIU W Z,GAO J G. Stiffness model of a machining robot[J]. Journal of Agricultural Machinery,2014(8):321-327.doi:10.6041/j.issn.1000-1298.2014.08.051 -
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