A contour-based path planning method for terrain-aided navigation systems with a single beam echo sounder

Abstract

Underwater terrain-aided navigation (TAN) methods with a single beam echo sounder (SBES) have the potential to facilitate long-term underwater navigation for underwater vehicles. However, the limited bathymetric measurement of the SBES often makes the accuracy and robustness of TAN navigational results greatly affected by the complexity of the terrain. Therefore, effective path planning for SBES-TAN is essential. This paper proposes a contour-based path planning method for SBES-TAN, which can yield robust navigational results even with noisy SBES measurements. Moreover, both the density and smoothness of contour lines are used to quantify terrain complexity. Moreover, a fuzzy comprehensive evaluation-based theory is used to identify TAN-suitable areas. Path planning is accomplished using the rapid-exploration random tree* algorithm, while a Monte Carlo-based TAN estimate handles the challenges posed by noisy SBES measurements. The performance of the proposed method has been verified through simulation using field bathymetric data, by comparing it with state-of-the-art methods.