Semiglobally Asymptotically Stable Nonlinear Observer for Camera Aided Navigation

Abstract

This brief presents a nonlinear observer that performs range estimation as well as gyro-bias estimation by using velocity, angular rate, and bearing angle measurements from landmarks at unknown locations. The observer is proved to have semiglobal asymptotic stability, and its performance is verified in simulations and on experimental data. The observer is demonstrated on an unmanned aerial vehicle (UAV) with a sensor setup consisting of camera, inertial measurement unit (IMU), and velocity measured by a global navigation satellite system (GNSS). This sensor suite is sufficient to replace the magnetometer and the altimeter.