Digital Terrain Model Based on Fractal Compensated Distance Inverse Weight Interpolation

In this paper, based on multibeam bathymetric sonar data, the inverse distance weighted (IDW) interpolation based on fractal compensated distance is combined with a terrain matching algorithm to construct an underwater digital terrain model (DTM), aiming to improve the navigation and positioning accuracy of an autonomous underwater vehicle (AUV) during prolonged underwater navigation. The performance of the proposed fractal-compensated interpolation and IDW interpolation is compared using the iterative closest contour point (ICCP) matching algorithm on a simulation platform. The experimental results show that the proposed interpolation algorithms are able to maintain high matching accuracy and positioning accuracy under different initial positioning errors. Compared with other interpolation methods, the digital terrain maps constructed using this algorithm have higher accuracy, fit the real terrain better, and have stronger robustness.