Position, Velocity, Attitude and Gyro-Bias Estimation from IMU and Position Information

Abstract

In this paper we consider the complete state estimation problem of a vehicle navigating in a three dimensional space. We assume that the vehicle is equipped with an Inertial Measurement Unit (IMU) and a sensor that provides some information about the position of the vehicle. Example of these sensors are those which provide full position measurements (e.g., GPS), range measurements (e.g., Ultra-Wide Band (UWB) sensors) or inertial bearing measurements (e.g., motion capture cameras). Regardless of the type of sensor used, we propose a generic nonlinear observer that estimates the position, velocity and the orientation of the vehicle along with the gyro bias. Exponential stability of the zero estimation errors is shown with a region of attraction that can be arbitrary enlarged. Simulation results using bearing measurements are provided to illustrate the effectiveness of the proposed estimation approaches.