Pose Optimization and Tool Path Planning for Robotic Grinding of Complicated Curved Surface

doi:10.3901/JME.2022.03.284

Abstract

Abstract: In recent years, robotic grinding with industrial robots as the executive body is gradually becoming the development trend of complex curved surface grinding due to its flexibility and versatility. In the process of robotic grinding, according to the curvature and normal direction on the surface, the tool path points are usually divided. However, the influence of the actual movement posture of the robot on the smoothness of the grinding path is not considered, and there may be interference between workpiece and tools. Therefore, it is difficult to guarantee the final machining accuracy. Therefore, a planning method that takes the change of the polishing posture as a constraint and smoothes the posture of the interference is proposed. Firstly, the robot's posture change are used as the threshold for dividing the tool position points, and the posture changes in other illegal line directions are considered, which slows down the posture changes. Then, interference problem is solved by changing posture at the interference point, and perform range smoothing with isoparametric circles. Finally, the posture change constraint and the posture smoothing of the interference tools are combined to plan a smooth and collision-free robot grinding and polishing path. The robotic abrasive belt grinding system is used to grinding experiments on aero-engine blades. The results show that the proposed method has smooth changes in joint angular velocity and better tool path smoothness. The contour of the blade after grinding meet -0.03~+0.05 mm tolerance zone, the surface roughness increases from Ra>3.2 μm to 0.247 2 μm. The effectiveness of the proposed planning method is verified.

Key words: robotic grinding, tool path, smoothing posture, interference, isoparametric circle

CLC Number:

V261
TP24

LUO Laizhen, ZHAO Huan, WANG Hui, LI Xiangfei, DING Han. Pose Optimization and Tool Path Planning for Robotic Grinding of Complicated Curved Surface[J]. Journal of Mechanical Engineering, 2022, 58(3): 284-294.

References

[1] WANG H,ZHU D,LIU J. Improving the accuracy of the blade leading/trailing edges by electrochemical machin-ing with tangential feeding[J]. CIRP Annals,2019,68(1):165-168.
[2] 黄云,肖贵坚,邹莱. 航空发动机叶片机器人精密砂带磨削研究现状及发展趋势[J]. 航空学报,2019,40(3):53-72. HUANG Yun,XIAO Guijian,ZOU Lai. Current situation and development trend of robot precise belt grinding for aero-engine blade[J]. Acta Aeronautica et Astronautica Sinica,2019,40(3):53-72.
[3] LIU D,SHI Y,LIN X,et al. Polishing surface integrity of TC17 aeroengine blades[J]. Journal of Mechanical Science and Technology,2020,34(2):689-699.
[4] WANG Tingting,ZOU Lai,WAN Qinghong,et al. A high-precision prediction model of surface roughness in abrasive belt flexible grinding of aero-engine blade[J]. Journal of Manufacturing Processes,2021,66:364-375.
[5] 刘树生. 航空钛合金叶片数控砂带磨削关键技术[J]. 航空制造技术,2011(4):34-38. LIU Shusheng. Key technology of NC abrasive belt grinding for titanium blade[J]. Aeronautical Manufacturing Technology,2011(4):34-38.
[6] 陈志同,易鹏,朱正清,等. 具有误差修正功能的叶片变预压量抛光技术[J]. 航空制造技术,2018,61(17):80-84,92. CHEN Zhitong,YI Peng,ZHU Zhengqing,et al. New aero-engine blade polishing technology available to correct machining errors through presetting wheel contact deformation[J]. Aeronautical Manufacturing Technology,2018,61(17):80-84,92.
[7] 蔺小军,杨艳,吴广,等. 面向叶片型面的五轴联动柔性数控砂带抛光技术[J]. 航空学报,2015,36(6):2074-2082. LIN Xiaojun,YANG Yan,WU Guang,et al. Flexible polishing technology of five-axis NC abrasive belt for blade surface[J]. Acta Aeronautica et Astronautica Sinica,2015,36(6):2074-2082.
[8] 段继豪,史耀耀,张军锋,等. 航空发动机叶片柔性抛光技术[J]. 航空学报,2012,38(3):573-578. DUAN Jihao, SHI Yaoyao,ZHANG Junfeng,et al.Flexible polishing technology for blade of aviation engine[J]. Acta Aeronautica et Astronautica Sinica,2012,33(3):573-578.
[9] QIU L,JI S,ZENG X,et al. Research on partition segment grinding path method of aero-engine blade based on robot group[J]. IEEE Sensors Journal,2019,99:1.
[10] 毛洋洋,赵欢,韩世博,等. 面向复杂曲面的机器人砂带磨抛路径规划及后处理研究[J]. 机电工程,2017,34(8):829-834. MAO Yangyang,ZHAO Huan,HAN Shibo,et al. Tool path planning and post-processing techniques of robotic belt grinding for complex surfaces[J]. Journal of Mechanical & Electrical Engineering,2017,34(8):829-834.
[11] 樊文刚,叶佩青. 复杂曲面五轴端铣加工刀具轨迹规划研究进展[J]. 机械工程学报,2015,51(15):168-182. FAN Wengang,YE Peiqing. Research progress in tool path planning for five-axis end milling machining of sculptured surfaces[J]. Journal of Mechanical Engineering,2015,51(15):168-182.
[12] PARK H,KIM K,LEE S C. A method for approximate NURBS curve compatibility based on multiple curve refitting[J]. Computer Aided Design 2000,32(4):237-252.
[13] MORISHIGE K,TAKEUCHI Y,KASE K. Tool path generation using C-space for 5-axis control machining[J]. Journal of Manufacturing Science and Engineering,1999,121(1):144-149.
[14] SURESH K,YANG D C H. Constant scallop-height machining of free-form surfaces[J]. ASME Journal of Engineering for Industry,1994,116(2):253-259.
[15] WANG Wei,YUN Chao. A path planning method for robotic belt surface grinding[J]. Chinese Journal of Aeronautics,2011,24(4):520-526.
[16] 林熊. 面向规则曲面磨削加工的机器人轨迹优化研究[D]. 武汉:华中科技大学,2019. LIN Xiong. research on robot trajectory optimization for regular surfaces grinding[D]. Wuhan:Huazhong University of Science and Technology,2019.
[17] 黄婷,许辉,樊成,等. 叶片复杂曲面的机器人抛磨工艺规划[J]. 光学精密工程,2018,26(1):132-141. HUANG Ting,XU Hui,FAN Cheng,et al. Robotic grinding process planning for complex blade surfaces[J]. Optics and Precision Engineering,2018,26(1):132-141.
[18] NG W X,CHAN H K,TEO W K,et al. Capturing the tacit knowledge of the skilled operator to program tool paths and tool orientations for robot belt grinding[J]. The International Journal of Advanced Manufacturing Technology,2017,91(5-8):1599-1618.
[19] ZHANG Tie,SU Jiewen. Collision-free planning algorithm of motion path for the robot belt grinding system[J]. International Journal of Advanced Robotic Systems,2018,15(4):172988141879377.
[20] 谢海龙,许晨旸,王清辉,等. 曲面零件机器人抛光轨迹规划与工艺仿真[J]. 自动化与信息工程,2019,40(06):1-7. XIE Hailong,XU Chenyang,WANG Qinghui,et al. Toolpath planning and process simulation for robot-assisted freeform surface polishing[J]. Automa-tion and Information Engineering,2019,40(06):1-7.
[21] 刘军,张俊,赵万华,等. 面向双刀加工的中长型叶片型面轨迹规划方法[J]. 机械工程学报,2016,52(11):140-145. LIU Jun,ZHANG Jun,ZHAO Wanhua,et al. Tool path generation for long turbine blades machined with twin-cutters[J]. Journal of Mechanical Engineering,2016,52(11):140-145.
[22] LIN Yang,ZHAO Huan,DING Han. Posture optimization methodology of 6R industrial robots for machining using performance evaluation indexes[J]. Robotics and Computer Integrated Manufacturing,2017,48:59-72.