面向钻削过程监测的振动信号处理及状态分类  

Vibration Signal Processing and State Classification for Drilling Process Monitoring

作　　者：代煜[1] 王景港 曹广威 张建勋[1] 贾宾 DAI Yu;WANG Jinggang;CAO Guangwei;ZHANG Jianxun;JIA Bin(Institute of Robotics&Automatic Information System,Nankai University Tianjin,300071,China)

机构地区：[1]南开大学机器人与信息自动化研究所,天津300071

出　　处：《振动．测试与诊断》2022年第1期89-95,196,197,共9页Journal of Vibration,Measurement & Diagnosis

基　　金：国家自然科学基金资助项目(61773223);天津市自然科学基金资助项目(18JCYBJC18800)。

摘　　要：易变形结构在钻削过程中因受力而产生形变,不能根据刀具的钻削距离判断刀具所处状态。钻削过程中刀具切入易变形结构不同的位置会产生不同幅度的振动,通过对加速度传感器采集到的振动信号进行快速傅里叶变换(fastFouriertransform,简称FFT),将钻削过程分为5个状态。通过计算系统基频整数次谐波分量幅值的变异系数,选取部分谐波分量的幅值作为特征量进行阶段监测。选用线性转换和对数转换相结合的方式实现输入数据的归一化,输入到支持向量机与多层前馈(backpropagation,简称BP)神经网络进行钻削状态分类。实验表明:支持向量机在所有钻削状态的识别准确率在85%以上,部分钻削状态的识别准确率达到了100%;BP神经网络分类器的识别准确率略低于支持向量机。根据所识别的状态控制刀具在即将钻透时停止,测量易变形结构剩余厚度验证了该方法的精确性。The deformable structure will be deformed by the force during the drilling process,and the state of the tool cannot be judged according to the applied feed distance.During the cutting process,the tool is cut into dif⁃ferent positions of the deformable structure to generate vibrations with different amplitudes.The vibration signal collected by the acceleration sensor is processed and analyzed by fast Fourier transform(FFT),and the drilling process can be divided into five states.The variation coefficients of all harmonic components are calculated,and then the amplitude of some harmonic components is selected as the feature for condition monitoring.Combina⁃tion of linear transformation and logarithmic transformation is used to achieve the normalization of the input data.The normalized results are imported into the support vector machine and the back propagation(BP)neural net⁃work for drilling state classification.Experiments show that the classification accuracy of the support vector ma⁃chine is above 85%in all drilling states,and the classification accuracy of some drilling states reaches 100%The classification accuracy of the BP neural network classifier is slightly lower than that of the support vector machine.According to the identified state,the tool is stopped when it is close to reaching the other side of the deformable structure,and the remaining thickness of the workpiece is measured to verify the proposed method.

关 键 词：钻削 振动信号 状态识别 快速傅里叶变换 支持向量机 

分 类 号：TP242[自动化与计算机技术—检测技术与自动化装置] TH781[自动化与计算机技术—控制科学与工程]