针对目前多数重构位移场的方法在实际工程应用中存在测点数量多、位置要求高等问题,引入机器学习建立了应变与位移之间的关系,实现了位移场的重构。分析LSTM、Transformer Encoder在动态变形重构中的精度和鲁棒性;然后设计加工槽型结构搭建实验平台,对槽道侧壁进行动态加载,通过采集系统和激光位移传感器对应变、位移信息进行采集,对比分析测试集的动态预测结果与传感器的测试结果;最后,融合LSTM和Transformer Encoder这2种神经网络,提出一种新的LSTM-Transformer Encoder(LTE)网络。结果表明:测试集上LSTM网络重构的节点最大平均误差为0.610%,Transformer Encoder重构的节点最大平均相对误差为1.010%。LSTM网络相比Transformer Encoder网络具有更好鲁棒性的同时重构精度更高,提出的LTE网络在测试集上具有更小的MSE(均方误差)及更大的R2(模型拟合系数),在整体的表现上优于LSTM和Transformer Encoder。
Aiming at the problems of large number of measurement points and high location requirements in most of the current methods for reconstructing displacement field in practical engineering applications, machine learning is introduced to establish the relationship between strain and displacement and realize the reconstruction of displacement field. We analyzed the accuracy and the robustness of the algorithms of LSTM and Transformer Encoder in dynamic deformation reconstruction; then we design and process the slot structure to build an experimental platform, dynamically load the sidewall of the slot channel, collect the strain and displacement information through the acquisition system and the laser displacement sensor, and transmit it to the computer, and then compare and analyze the dynamic prediction results of the test set with the test results of the laser displacement sensor; finally, a new LSTM-Transformer Encoder (LTE) network is proposed by fusing two neural networks, LSTM and Transformer Encoder. The results show that the maximum average error of the nodes reconstructed by the LSTM network on the test set is 0.610%, and the maximum average relative error of the nodes reconstructed by the Transformer Encoder is 1.010%.The LSTM network has better robustness than the Transformer Encoder network with higher reconstruction accuracy, and the proposed LTE network has smaller MSE (mean squared error)and larger R2 (model fit coefficient) on the test set, which is better than the LSTM and Transformer Encoder in the overall performance.
2025,47(22): 38-45 收稿日期:2025-2-27
DOI:10.3404/j.issn.1672-7649.2025.22.006
分类号:U661.43
基金项目:国家自然科学基金资助项目(51839005)
作者简介:白金川(2002 – ),男,硕士研究生,研究方向为机器学习、减振降噪
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