ID2TM: A Novel Iterative Double-Cross Domain-Center Transfer-Matching Method for Underwater Gravity-Aided Navigation

Gravity-assisted inertial navigation technology has been widely used in the underwater navigation communities. However, the traditional gravity matching algorithm has low efficiency and may cause out-of-domain mismatching, resulting in a significant increase in positioning errors, which affects the long-term high-precision navigation of underwater vehicles. To solve these problems, iterative double-cross domain-center transfer-matching algorithm (ID2TM) is proposed with iterative double-cross line rough matching and local adaptive small-domain fine matching mechanism. The experimental results show that the proposed ID2TM algorithm has excellent matching performance in improving the underwater navigation positioning efficiency and matching reliability. Meanwhile, three tests in different gravity zones show that its worst matching accuracy and positioning efficiency are 93% and 84% higher than TERCOM on average, and the out-of-domain mismatching is completely avoided, which further verified that ID2TM has good location applicability in different gravity regions.