面向航空发动机复杂机匣深腔测量的机器人位姿优化及关节路径平滑方法  

Robot Pose Optimization and Joint Path Smoothing Method for Aero-engine Complex Casing Deep Cavity Measurement

作　　者：漆琪 杨吉祥 丁汉[1] QI Qi;YANG Jixiang;DING Han(State Key Laboratory of Digital Manufacturing Equipment and Technology,Huazhong University of Science and Technology,Wuhan 430074)

机构地区：[1]华中科技大学数字制造装备与技术国家重点实验室,武汉430074

出　　处：《机械工程学报》2023年第15期17-27,共11页Journal of Mechanical Engineering

基　　金：国家重点研发计划(2020YFB1710400);国家自然科学基金(52122512,52188102);湖北省自然科学基金(2021CFA075)资助项目。

摘　　要：航空发动机机匣铸造件内腔余量分布不均且结构复杂,为实现机匣内腔余量的准确去除,须对机匣内腔轮廓进行精准测量。采用工业机器人夹持激光位移传感器,可充分发挥机器人灵巧运动的特点,实现复杂腔体的测量。但现有机器人加工刀具路径生成方法大多针对铣削、磨抛加工,主要关心路径的可达性,而未考虑非接触式测量中的夹角约束和路径平滑,直接应用于机器人测量导致测量角度无法满足要求、传感器振动大等问题。提出了一种面向机器人测量位姿优化及运动光顺的无干涉路径规划方法。首先,基于距离的干涉检测构建测量路径点的无碰撞区域,建立以机器人关节加速度为性能指标,考虑激光束出射方向与曲面法向夹角、机器人关节限位的优化函数,将姿态控制求解转变为优化函数的求解,采用分段差分进化算法进行求解。对测试路径进行实验并与基于图形的方法进行对比,结果表明,所提出的路径规划算法可有效约束测量方向与曲面法向之间的夹角,且与基于图形搜索的方法相比,可以生成更平滑的机器人关节路径,运行时间缩短50.3%,x、y、z方向的末端瞬时加速度分别减小15.83%、30.45%、41.72%。The inner cavity margin of aero-engine casing castings is unevenly distributed and has a complex structure.To accurately remove the inner cavity margin of the casing,it is necessary to accurately measure the contour of the inner cavity of the casing.It can give full play to the characteristics of the robot's dexterous movement and realize the measurement of complex cavities by using industrial robots with the displacement sensor.However,most of the paths generated by the robot machining tool path generation method consider interference avoidance optimization in the milling,grinding,and polishing and the main concern is the accessibility of the path.Since the angle optimization in non-contact measurement is not considered,it will lead to the problems of larger fluctuations in joint displacement and larger sensor vibration.An interference-free path planning method for robot measurement pose optimization and motion smoothing is proposed.First,the interference-free area for the path point is established with the method of a distance-based interference detection,and the optimization function is established with the acceleration of the robot joint as the performance index which considering the angle between the laser incident direction and the surface normal,the limit of the robot joint.The question is transformed into solving the optimization function by using a piecewise differential evolution algorithm to solve.Experiments are performed on a given path and compared with the graph-based method.The proposed path planning algorithm can effectively constrain the angle between the measurement direction and the surface normal,and can generate smoother robot joint paths compared with methods based on graph search.The running time is shortened by 50.3%,and the instantaneous acceleration of the terminal in the x,y,and z directions is reduced by 15.83%,30.45%,and 41.72%.

关 键 词：机器人测量 无干涉区域 位姿优化 运动光顺 差分进化算法 

分 类 号：TP242[自动化与计算机技术—检测技术与自动化装置]