Review: Tilt-Free Low-Noise Seismometry
نویسندگان
چکیده
Inertial instruments used to measure horizontal motion are sensitive to tilt. Tilt coupling induced by gravity exerting a force along the sensing axis of the instrument as a function of its inclination must be accounted for in numerous seismological studies and seismic isolation applications. There are, in theory, many ways to separate tilt and horizontal motion components by combining the measurements of several sensors, and produce tilt-free estimations of the horizontal motion. This article reviews these configurations and analyses limitations related to sensor noise and geometrical couplings. It concludes with a discussion on the use of suspension mechanisms as an alternative to signal subtraction methods.
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