Study on Correspondence between output voltage of cable censer for vibration detection and velocity

摘要

There are many unstable slopes which face to main routes, particularly in northern territories in Japan. It is considered that small rockfalls must occur preceded to the slope failure of big scale?referring to some reports on rock failures. Under these social requirements, rockfolls monitoring system composed of string type cable sensor for vibration detection and signal transmission was developed to detect the warning signs of slope failure. But the certain value, acceleration, velocity and displacement of the output voltage has not been decided clearly. if the output voltage of the cable sensor can be transformed into the certain value, acceleration, velocity and displacement, the effectiveness of the system using the cable sensor raise more. Aim of this study is "To understand the relationship between the output voltage of the cable sensor and the certain value". And so first, the frequency characteristic analytic examination was conducted by using the giant-magnetstriction vibrator to investigate the certain value to which of acceleration, velocity and displacement corresponding with output voltage of the cable sensor. It was obtained that the velocity waveform could be transformed as that result. Next, the frequency transfer function was obtained between the output voltage of the cable sensor and the velocity. Finally, the output waveform of the cable sensor is transformed into the velocity waveform by using the frequency transfer function. As the result of this study, the value of the maximum velocity of two waveforms showed reconciliation. And the form of the waveform could comparatively trace the real velocity waveform. It can be said that the velocity transformed well accurate.