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.%以两端弹性支撑梁为研究对象,测量了激励力作用下测点(测点数大于激励点数)的时域响应及相应测点的加速度导纳,并利用最小二乘法间接估算了激励力.针对激励频率处响应受噪声干扰小、信噪比高的特点,提出了基于估算力曲线分段相似性的激励频率判定方法.采用该方法进行了激励频率判定分析,并将其结果与传统识别结果进行了对比.对比结果表明,该方法有效地降低了误识别率,并实现了激励频率判定的半智能化.
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