A Line-surface Integrated Algorithm for Underwater Terrain Matching

The current underwater terrain surface matching algorithm,which uses Hu moment as similarity index, cannot gain fairly precious location due to its disadvantage in detecting slight difference.To solve this problem,a line-surface integrated terrain matching algorithm is presented.Firstly,the similarity evaluation method of traditional terrain contour matching (TERCOM) algorithm is improved,and strategy used to select the matching regions is developed.Then,a surface matching algorithm based on geometric similarity is established to find the optimum matching of real terrain.Finally,an integration means of the "line matching algorithm" and "surface matching algorithm" based on fixed threshold is proposed.Experimental results show that the proposed algorithm can obtain much higher location precision and better robustness than the surface underwater matching algorithm based on Hu moment