FAULT TOLERANT INTEGRATED NAVIGATION SYSTEM DEVELOPMENT PROGRAM

THE TOP LEVEL DESIGN AND SIMULATION OF A FAULT TOLERANCE, FAIL-SOFT INTEGRATED NAVIGATION SYSTEM IS PROPOSED. THE PROPOSED ARCHITECTURE CONSISTS OF A RING LASER GYRO, CORRELATION VELOCITY SPEED LOG, HEADING AND ATTITUDE SENSORS, KEEL DEPTH AND ALTITUDE SENSORS, AND A SHAFT TURNS-RATE SENSOR. AN EXTREMELY HIGH MEAN TIME BETWEEN FAILURE FIGURE IS EXPECTED TO RESULT FROM THE APPLICATION OF BOTH HARDWARE AND SOFTWARE FAULT TOLERANCE TECHNIQUES. THE SOFTWARE FAULT TOLERANCE TECHNIQUES INCLUDE THE DEVELOPMENT OF ROBUST DATA TRANSMISSION SOFTWARE, SOFTWARE VALIDITY ALGORITHMS, AND REDUNDANT POSITION COMPUTATION ALGORITHMS. REVERSIONARY MODES OF OPERATION ARE PLANNED TO ACCOMMODATE CONTINUED OPERATION IN THE FACE OF SENSOR FAILURES. THE PERFORMANCE OF THE SOFTWARE FAULT TOLERANCE SHALL BE VERIFIED THROUGH SIMULATION. CRITICAL NAVIGATION SENSORS SHALL BE REPLICATED AS REQUIRED.