IMU Accuracy Enhancements for Ground-based Midcourse Defense (GMD)

Improvements to the GMD EKV on-board INS includes augmentation of the IMU with GPS aiding. Uncorrected IMU errors and vehicle attitude errors impact the total EKV pointing error. The application of emerging low-cost MEMS based sensors creates new opportunities to include GPS aiding without sacrificing mass, volume and cost of the current EKV INS. The Archangel approach builds upon the existing miniature Inertial Measurement Cube (IM3) with modifications and additional compensation features to meet EKV goals. Starting with the IM3 enables immediate development of the needed combination of Fuzzy Logic Adaptive Signal Processing (FLASP) and Ultra-Tight Coupling compensation schemes. The output of the FLASP algorithm can be a complete INS solution with either tightly or ultra tightly coupled GPS. We propose a feasibility study that demonstrates the potential for reaching the very tight bias drift and random walk requirements of the EKV. The study will determine a baseline performance of an unaided IM3 used to compare with a GPS/INS coupled system