Seabed Terrain Establishment Based On Scattered Bathymetric Data And Research Of Visualization Method

Exact reproduction of 3D seabed terrain has very high application value, it not only provides the service for path planning and navigation of submarine, but also it provides strong supporting platform for Voyage Training simulation and the environment of sea battlefield simulation. This paper mainly studies the process of the realistic 3D seabed terrain established based on scattered bathymetric data, the content of as follows:Firstly, the data storage way of two-dimensional electronic chart is studied, Designing and developing automated procedures depth of bathymetric data, and the extracted depth information is automatically stored in a text file.Secondly, studying modeling method for spatial data based on scattered points. By analyzing the characteristics of scattered bathymetry data and seabed terrain, this paper proposes the idea of subregional interpolation on the terrain. IFS fractal interpolation method is used in data sparse and rough terrain areas, but in the areas of data dense and flat terrain the improved Moving Green Function Spline Interpolation is used. In addition, in order to obtain interpolated information simply and intuitively, the COM interface programming technology of VC and Matlab is used to develop terrain generation module, it can automatic generate interpolation information and seabed terrain data model.Thirdly, the terrain generation algorithm is improved. Analyzing the problems of IFS fractal interpolation, by adopting moving surface idea and making use of the local self-similarity of seabed terrain, the method of this paper maps rectangular subfield which consists of the cells around the centre interpolated cell to the interpolated cell by using IFS fractal interpolation, and this paper uses elevation to calculate vertical scale factor creatively.The results show that this method both in precision, and stability are improved greatly, and data partitioning and smooth edging is unnecessary so that the complexity of this method is greatly reduced.According to the interpolation result of improved Moving Green Function Spline is still short of stability, this paper proposes the idea of combining it with distance-weighted a'verage arithmetic. It could learn from other's strong points to offset one's weakness. Furthermore,before the Surface fitting, we judge and preprocess the depth water points that we have searched. The results show that seabed terrain which is established by this method has high precision and good stability. Besides, comparing with the moving green function spline interpolation, the computing time of this method is shorter.Last, by using the Creator modeling software a test terrain is created, through pasting texture and doing other operations in this test terrain, 3D seabed terrain database of simulation requirements is generated. And the Vega applications based on MFC is designed and developed in the Visual C++ environment, it can achieve the simulation of realistic 3D seabed terrain.