DISPLACEMENT QUANTITY MEASURING METHOD

PURPOSE:To reduce an error due to a gravitational acceleration component and to improve the measurement accuracy by fitting a strain conversion type accelerometer to a structure in an oscillatory state. CONSTITUTION:A pendulum 9 is fitted to the structure and the strain conversion type accelerometer 4 is fitted to the pendulum 9. Thus, the pendulum 9 is inter posed to eliminate the inclination of the accelerometer 4 even if the structure 2 slants from a broken-line state as shown by a solid line, thereby holding the sensitivity direction horizontally. In this case, an error due to the individual motion of the pendulum 9 is a problem. The length (l) of the pendulum 9, how ever, is adjusted to enable the error to be ignored. The sensitivity direction of the accelerometer 4 is, therefore, held horizontally and the influence of gravi tational acceleration is eliminated.