【摘要】 目的提出一种考虑能耗的多传感器融合加工表面粗糙度预测方法,精确预测零件表面粗糙度。方法首先采集车削过程中的功率和振动信号,测量加工表面粗糙度值,利用集成经验模态分解(Ensemble empirical mode decomposition,EEMD)和小波包分析提取振动信号的时域与频域特征,联合功率信号的时域特征、能耗特征与切削参数,构造联合多特征向量。然后采用核主成分分析(Kernel principal component analysis,KPCA)对联合多特征向量进行融合降维处理生成融合特征。最后将融合特征作为基于支持向量机(Support vector machine,SVM)的表面粗糙度预测模型的输入特征,并使用遗传算法(Genetic algorithm,GA)对SVM模型相关核参数进行优化以提高预测精度。结果预测得到的表面粗糙度平均相对误差为4.91%,最大误差为0.111μm,预测时间为9.24 s。与单传感器预测方法及多传感器联合特征预测方法相比,多传感器融合预测方法具有最高的准确率且预测速度快。结论多传感器采集的信息更全面、准确,保证了预测的准确性,对特征进行融合可进一步提高预测精度。更多还原

【Abstract】 In order to predict surface roughness of the workpiece accurately, an approach for surface roughness prediction in machining based on multi-sensor fusion considering energy consumption is proposed. The power signal and the vibration signal of the turning process were collected firstly. Surface roughness was measured. The time domain and frequency domain characteristics of the vibration signal were extracted by using the EEMD and wavelet packet analysis. And the vibration features with the time domain feature of power signal, energy features and cutting parameters constructed the joint multi-eigenvectors. Then the KPCA was used to fuse the joint multi-eigenvectors to generate the fusion feature. Finally, the fusion feature was taken as the input characteristic of the SVM-based surface roughness prediction model. In addition,GA was used to optimize the relevant kernel parameters of SVM model to improve the prediction accuracy. For the prediction results obtained by multi-sensor fusion, the mean relative error was 4.91%, the maximum error was 0.111 μm and the prediction time was 9.24 seconds. The experimental results showed the proposed method had the highest prediction accuracy compared with the joint feature and single sensor. A comparative study with multi-sensor joint feature prediction method and signal-sensor feature prediction method shows the information collected by multi-sensor is more comprehensive and accurate, which ensures prediction accuracy and the prediction accuracy can be further improved by fusing the features.更多还原