Single GPS Antenna Attitude Determination of a Fixed Wing Aircraft Aided with Aircraft Aerodynamics

Abstract

The satellite-based Global Positioning Systems (GPS) creates a new era for navigation, surveying and geodesy. Precise airborne and shipboard navigation, precise static geodetic positioning over baselines from a few meters up to thousands of kilometers, and kinematic positioning are just a few among numerous applications of GPS. In addition to providing position and velocity information, the GPS system can also be used to estimate the attitude parameters of the platform. It has the potential of replacing, to some extent, some sophisticated and expensive attitude sensors such as Inertial Navigation Systems (INS). Recently, a considerable amount of efiort has been directed at developing low-cost systems for attitude determination. Methods to determine the attitude of the aircraft using a known wind vector and angle of attack and a single antenna GPS receiver already exist. In this colloquium a new method for attitude determination using a single GPS receiver aided with an aerodynamic model and a Kalman fllter will be presented. Using no additional information but a single GPS receiver the complete attitude of the aircraft and the wind vector will be estimated. Results from simulation and real aircraft log flles will be shown. When the ∞ight path is adapted to the attitude determination algorithm for wind estimation the aircraft is required to ∞y a turn at a constant velocity, accuracies of a few degrees for all attitude angles can be obtained. The faster the update rate of the GPS receiver, the more accurate the method becomes at estimating the faster dynamics of the aircraft. In the future this method could prove a useful addition to the cockpit as a backup attitude determination system for General Aviation, or as primary attitude determination system for use in Unmanned Aerial Vehicles.