Highly Accurate Inertial Navigation that Compensates for the Earth’s Rotation and Sensor BIAS Using Non-Holonomic Constraints

Abstract

This proposal presents a means of increasing the accuracy of inertial navigation (IN) by isolating the Earth's rotation and sensor bias. It is designed as a means of navigation for moving objects using just an IMU without any external sensors. By eliminating the Earth's rotation, which is a factor that leads to IN errors, even with online processing during movement, IN measurement errors were reduced from approximately 20 m every 60 seconds to just 2 m. In order to isolate the angular velocity of the Earth from the angular velocity of a moving object, we focused on non-holonomic constraints (NHC) and optimized the index of precision to minimize velocity errors, allowing us to successfully isolate the Earth's rotation and separate it from gyroscope bias during motion. As a result, the conventional “maytagging” method, whereby complex calibrations are carried out on the stationary object before movement, is rendered unnecessary.