Developing a Simple True North Finder Using MEMS Inertial Sensors

Abstract

In recent days, inertial sensors based on micro electro mechanical systems (MEMS) technology have been remarkably miniaturized and highly accurate. These sensors have led to the development of compact and inexpensive true-north finders compared to conventional gyroscopes. Accuracy, price, and time required to measure the true north are in a trade-off relationship with each other. We focus on the fact that the direction of seismometer installation does not require such high accuracy and developed a prototype for a rapid measurement system of true north using a 6-component MEMS inertial sensor made of crystal oscillators, specifically for measuring the azimuth angle of seismometer installation. We discuss operations for measurement and algorithms for analyzing the data, and confirmed the prototype worked well.