Nonlinear Methods for Failure Detection & Isolation

ZC&H Dynamic Systems proposes the design, prototype and test of an instantaneous RAIM algorithm based on nonlinear regression that will exploit both pseudorange-based position-bias information and delata- pseudorange-based velocity-frequency offset information. This is in contrast to the RTCA's currently proposed linear regression algorithms based solely on pseudoranges. This RAIM algorithm will provide superior instantaneous detection of GPS outliers over the currently proposed RTCA method and will also provide a dynamic method to detect integrity failures resulting from small error drifts over time. ZC&H also proposes to modify its two-stage nonlinear GPS/INS integration filter for integrity monitoring. This algorithm has been designed to work with very low cost solid state inertial sensors. Test and simulation support, along with advice regarding requirements for non-precision and precision support, will be provided by ARINC Research corporation.