Page 116 - Autonomous Mobile Robots

3 Data Fusion via Kalman

Filter: GPS and INS

Jingrong Cheng, Yu Lu, Elmer R. Thomas, and
Jay A. Farrell

CONTENTS

3.1 Introduction ............................................................ 100
3.1.1 Data Fusion — GPS and INS................................. 101
3.2 Kalman Filter .......................................................... 102
3.2.1 Stochastic Process Models.................................... 102
3.2.1.1 Computation of and Q ......................... 104
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3.2.2 Basic KF ....................................................... 105
3.2.2.1 Implementation issues.............................. 107
3.2.3 Extended KF................................................... 109
3.3 GPS Navigation System ............................................... 113
3.3.1 GPS Measurements ........................................... 113
3.3.2 Single-Point GPS Navigation Solution....................... 115
3.3.3 KF for Stand-Alone GPS Solutions .......................... 119
3.3.3.1 Clock model ........................................ 120
3.3.3.2 Stationary user (P model) .......................... 121
3.3.3.3 Low dynamic user (PV Model) .................... 122
3.3.3.4 High dynamic user (PVA model) .................. 122
3.3.3.5 GPS KF examples .................................. 123
3.3.3.6 Summary............................................ 127
3.4 Inertial Navigation System ............................................ 128
3.4.1 Strapdown System Mechanizations .......................... 129
3.4.2 Error Model of INS System................................... 131
3.4.3 EKF Latency Compensation .................................. 131
3.5 Integration of GPS and INS ........................................... 132
3.5.1 INS with GPS Resetting ...................................... 133
3.5.2 GPS Aided INS................................................ 133
3.5.2.1 Loosely coupled system............................ 134
3.5.2.2 Tightly coupled system............................. 135
3.6 Chapter Summary...................................................... 142

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© 2006 by Taylor & Francis Group, LLC

FRANKL: “dk6033_c003” — 2006/3/31 — 16:42 — page 99 — #1