抄録
Measurement and analysis of fluctuations of structural objects are useful for monitoring the condition of these structures. In this paper, we propose a laser beam technique for studying these fluctuations, and report some results of our investigations, including an observation of forced vibration of a refrigerator, rotational frequency of an electric motor, and the appearance of a fluctuation in rotational speed due to fatigue. This technique has also been applied to real structural objects, a resonance of a automobile due to rotation of the engine, and intrinsic vibrations of buildings. Standard techniques used in fluctuation analysis are compared in a detection of an abnormal state of an electric motor. Data processing techniques of higher-orders are tested. Fluctuation analysis should be an important objective of analytical chemistry. The results obtained with this laser beam technique should form a useful collection of data regarding fluctuation analysis of various objects.