基于6自由度串联机器人的电火花铣削加工轨迹规划及伺服控制策略研究  

Trajectory Planning and Servo Control Strategy of EDM Milling Based ona 6-DOF Serial Robot

作　　者：岳晓明 臧烁 徐作珂 张勤河[1,2] 张建华[1,2] 霍孟友[1,2] YUE Xiaoming;ZANG Shuo;XU Zuoke;ZHANG Qinhe;ZHANG Jianhua;HUO Mengyou(School of Mechanical Engineering,Shandong University,Jinan 250016;Key Laboratory of High Efficiency and Clean Mechanical Manufacture,Ministry of Education,Shandong University,Jinan 250016)

机构地区：[1]山东大学机械工程学院,济南250061 [2]山东大学高效洁净机械制造教育部重点实验室,济南250061

出　　处：《机械工程学报》2023年第9期20-27,共8页Journal of Mechanical Engineering

基　　金：国家自然科学基金(51905311);中国博士后科学基金(2022T150383);山东省自然科学基金(ZR2020ME163)资助项目。

摘　　要：针对传统电火花铣削加工所存在的灵活性不足和被加工工件尺寸受限等问题,提出了基于6自由度串联机器人的电火花铣削加工方法。基于四元数理论建立了工具电极复杂轨迹规划方法,实现了工具电极变姿态铣削加工。为了解决串联机器人无法满足电火花加工对放电间隙实时调整的快速响应要求,提出了工具电极垂直轨迹回退的伺服控制策略,实现了对加工间隙的快速调整。利用机器人的3个自由度和6个自由度分别开展了工具电极定姿态和变姿态下的电火花铣削加工实验,实验结果表明当工具电极变姿态时,加工过程中工具电极端部与工件表面发生放电,铣削加工轨迹的槽宽略大于工具电极直径,因此工具电极变姿态电火花铣削加工曲面工件时精度和效率更高。最后,在半球形工件上实现了电火花铣削加工三种复杂轨迹,验证了基于6自由度串联机器人电火花铣削加工技术的可行性和有效性,具有很大的市场应用潜力。Aiming at the problems of insufficient flexibility and limited size of workpiece in traditional EDM milling,an EDM milling method based on a 6-DOF serial robot is proposed.Based on quaternion theory,the complex trajectory planning method of tool electrode is established to achieve the variable attitude milling of tool electrode.To solve the problem that the serial robot cannot meet the rapid response requirements of EDM for real-time adjustment of discharge gap,a servo control strategy of tool electrode vertical trajectory fallback is proposed to realize the rapid adjustment of machining gap.Using three and six degrees of freedom of the robot,the EDM milling experiments under fixed attitude and variable attitude of tool electrode are carried out,respectively.The experimental results show that the discharges occur between the end of tool electrode and the surface of workpiece with variable attitude milling of tool electrode,and the groove width of milling track is slightly larger than the diameter of tool electrode,Therefore,the precision and efficiency of EDM milling curved workpiece with the variable attitude of tool electrode are higher.Finally,three complex tracks are machined by EDM milling on the hemispherical workpiece,which verifies the feasibility and effectiveness of EDM milling based on a 6-DOF serial robot,and this method has a great market application potential.

关 键 词：电火花铣削加工 6自由度串联机器人 轨迹规划 伺服控制策略 三维曲面加工 

分 类 号：TG156[金属学及工艺—热处理]