THE THEORETICAL AND EXPERIMENTAL VALIDATION OF THE GPS-INS-STAR HYBRID NAVIGATION SYSTEM CONCEPT

Abstract

The theoretical and experimental validation of the GPS-INS-STAR hybrid navigation system is performed. The hybrid navigation system combines the best features of employed sensors to improve the total navigation performances. The GPS-INS-STAR hybrid navigation system (Tanabe, 1984, 1985) consists of the three different sensors, i.e. a GPS receiver, an Inertial Navigation System and a STAR image sensor. In this concept, the system integrates a high positioning performance of the GPS system, an accurate attitude determination capability of the STAR image sensor and the INS signal with a wide bandwidth. It results in a complete 6-DOF (Degree Of Freedom) autonomous navigation system. The validation of the concept is performed in the previous paper (Tanabe, 1988) by the experiments, using GPS, INS and STAR hardware systems. The present paper extends the experiment furthermore where the various configurations of the hybrid system are compared. The paper also shows a theoretical description of the experimental results. In the theoretical analysis, it is said that the concept of observability well explains the performances of the hybrid navigation system. It is also stressed in this paper that we can design, by this theoretical method, the appropriate configurations of the hybrid system which correspond to various missions.