An Inexpensive and Robust GPS/INS Attitude System for Automobiles

摘要

Many of the sophisticated control systems of modern automobiles require measurements of the vehicle's attitude. Commercial GPS attitude systems are the method of choice for measuring attitude in many aircraft and farm vehicle applications, but are not commonly used on automobiles. The prohibitive aspects of commercial GPS attitude systems on a car include their relatively high cost and significant loss of integrity and signal availability in urban road environments. This paper gives an overview of current research involving the development of an inexpensive and robust GPS-INS attitude system for automobiles. The prototype system is built from relatively low-cost GPS receivers and automotive-grade INS components. The robustness of the GPS-attitude solution has been greatly enhanced by a combination of methods, including INS-aided integer searches and verification, noisy measurement identification, and exploiting multiple-baseline redundancy. This system also has the unique ability to determine attitude (yaw, pitch, and roll) with only one satellite, which significantly increases GPS attitude availability in urban environments. In numerous road tests, the system has demonstrated degree-level accuracy and GPS yaw measurement availability about 95% of the time, even in urban areas. The system also shows a high level of robustness in adverse conditions for GPS signals (foliage, buildings), and compares favorably to other GPS attitude systems in such environments.