Micro Electro Mechanical Sensors, a major breakthrough in positioning, an asset for security

Transcription

1 > Micro Electro Mechanical Sensors, a major breakthrough in positioning, an asset for security Prepared by: Marc REVOL (THALES) GALILEO Days 2010 Session 3: Technologies for applications 5 March 2010, Brussel

2 GNSS receivers vulnerabilities Interference GALILEO Satellites GPS Satellites Masking GNSS availability and continuity sensitive to local environment (multipaths, interferences, masking) Navigation robustness can be complemented by lot of other sensors Interference # 2 Interference # 1 Multipaths Interference Antenna Multipaths GNSS signal Masked GNSS signal GNSS receiver Urban Canyon Signal generated S/N degradation & Measures bias Environment Background Interferences >> GPS/Galileo 2

3 » Hybridization of GNSS receiver: Added-value of hybridized systems High rate output & short term accuracy based on inertia - Accurate & safe attitude & navigation Inertial sensors (low grade) - Improved continuity GNSS Receiver Inertial drift corrected by GNSS measurements» provides alternate solution to high performance & expansive attitude & navigation equipements A cost effective improvement of GNSS signal weaknesses 3

4 Principle of a stand-alone Inertial System 2 kinds of sensors Algorithms Angular rates Gyrometers Angular rates Computer Accelerations Attitudes Accelerations 3D Position 3D Velocity Accelerometers Inertial Measurement Unit (IMU) Inertial information is always: Available Autonomous Safe/ Integer Reliable 4

5 0.001 /h Gyro accuracy Electo-mechanical Gyro technology evolution Optical 0.01 /h 0.1 /h Gyroscope Single axis 12 et 33 cm Pixyz 22 New optical gyro Spinning Wheels Pixyz 14-1 MEMS 1 /h Pixyz /h (Vibrating) (Micro Electro Mechanical) technologies required for a complete offer Our choice: Optical and MEMS 5

6 Accelerometer accuracy Accelerometer technology evolution 10 µg Electro mechanical pendular 100 µg Mical A90 HP A90 1 mg 10 mg J AQM (pendular) A100 Quartz Silicon MEMS (Micro Electro Mechanical Sensor) A single technology: MEMS, may fullfill all needs 6

7 System Segmentation vs sensor accuracy» IMU class gained through GNSS hybridization (nominal GNSS environment): 10 µg 100 µg Accelerometer accuracy Future Civil AHRS/GNSS Launchers MEMS High-End + Continuous IMU GNSS Civil Aero Navigation Military Aero Navigation Military Land Navigation 1 mg 10 mg Short range Missiles Stand-By Flight Controls AHRS MEMS IMU w/o GNSS Amunitions Cruise Missiles Thanks to GNSS hybridization, without GNSS outage Gyrometer accuracy 100 /h 10 /h 1 /h 0.1 /h 0.01 /h /h 7

8 Conclusion: some recommendations Hybridisation is intended to satisfy user needs in most of the cases where SIS blockage or degradation may occur in particular: - urban canyon (masking, multipaths) - interferences - High user dynamic or where High Continuity (beyond Galileo/GNSS requirement) is required MEMS technologies are intended to provide low-cost and accurate navigation and attitude, once merged with GNSS services For most demanding applications, the performance of hybridisation can be improved by other techniques or sensors : use of multiple constellations, map matching, MEMS & GNSS hybridation, a major breakthrough in positioning and security 8

9 Thank you for your attention For further comments or more detailed explanations, please contact : Marc Revol 25, rue Jules Védrines Valence - France Tél; Fax; marc.revol@fr.thalesgroup.com NAV/10/