MEMS Gyro and Accelerometer as North-Finding System for Bulk Direction Marking

Abstract

The ability to seek the accuracy of the true north direction is essential in determining the direction of the ground vehicle, sea, and air and as a reference point in the determination of Qibla direction as well. Theodolite is mainly used for surveying applications in measuring angles, including determining the direction for Muslims to perform ritual prayers, Qibla. However, transferring point-by-point from outdoor to indoor via theodolite requires many experts and is a complicated process. In this paper, we present the development of a highly accurate and compact north-finding prototype for bulk direction marking based on a Micro-Electro-Mechanical System (MEMS) gyroscope and accelerometer sensor. The system consists of two modules; a GPS-based transmitter module to obtain latitude and longitude information and a MEMS gyroscope and accelerometer-based receiver module to detect the geographic north and mark the direction. We accomplish the accuracy by implementing a 4-point static rotation method to compensate for the gyroscope bias and a digital complementary filter system to filter out drift error and fluctuations in the data. We tested the developed prototype on different geographic landscapes, weather conditions, and various building types. The field test results prove that the developed system achieves an accuracy of ±7’ 06”, verified by the Department of Survey and Mapping Malaysia.

Keywords

• Accelerometer
• direction marking
• geographic north
• GPS
• gyroscope sensor
• MEMS gyroscope