关键词: 最小二乘法, 激励源识别, 导纳, 相似性判定

Abstract:

A beam with elastic supports on both ends was chosen as the research object.The experiments on time domain response of the measured points(the number of the measured points were larger than the number of the excited points) and the corresponding acceleration admittances were done.Taking use of least
squares method,exciting forces were estimated indirectly.For the characteristics of the low noise contamination and high signal to noise ratio at the exciting frequencies,a approach about exciting frequencies judgement based on the segment similarity of the estimated exciting source curves was proposed.By means of  this method the exciting frequencies judgment analysis was done,and the analysis results were compared with the results obtained by the conventional analysis.The comparison results indicate that with application of the presented method,the recognition accuracy and effect are well improved.Meanwhile,the semi-intelligent in the exciting frequencies judgement  is achieved,which is very important for the engineering applications.

Key words: least square method, exciting source identification, admittance, similarity judgement