Effects of Initial Attitude Estimation Errors on Loosely Coupled Smartphone GPS/IMU Integration System

TL;DR

This paper investigates how initial attitude estimation errors impact the performance of EKF-based GPS/IMU integration in smartphones, highlighting the importance of accurate initial states for reliable navigation.

Contribution

It provides an analysis of the effects of initial errors on attitude estimation in loosely coupled GPS/IMU systems using EKF, based on outdoor experimental data.

Findings

Initial attitude errors significantly degrade EKF performance.

Navigation solutions diverge rapidly with increasing initial errors.

Experimental results quantify the sensitivity of attitude estimation to initial inaccuracies.

Abstract

Global Positioning System (GPS) and inertial measurement unit (IMU) sensors are commonly integrated using the extended Kalman filter (EKF), for achieving better navigation performance. However, because of nonlinearity, the performance of the EKF is affected by the initial state estimation errors, and the navigation solutions, including the attitude, diverge rapidly as the initial errors increase. This paper analyzes the data obtained from an outdoor experiment, and investigates the effect of the initial errors on the attitude estimation performance using EKF, which is used in loosely coupled low-cost smartphone GPS/IMU sensors.