Multi-beam Outlier Detection Algorithm Based On CUBE And Display And Control Software

Multibeam bathymetric technology, which is the most important method for ocean exploration, is widely used in ocean monitoring and seabed resources investigating. As it cannot gain the absolute true depth and the measurements are effected by many uncertain factors, it is difficult to estimate its quality of soundings directly in the process of multibeam bathymetry. Moreover, it is inevitable to have outliers in bathymetric data, which may lead to the formation of false seafloor topography, the further application of measurements, and the waste of manpower and material resources. So it urgently needs a efficient and robust method to detect and eliminate outliers automatically. As mentioned above, this thesis suggests a method based on CUBE(Combined Uncertainty Bathymetry Estimator), of detecting outliers automatically in multibeam bathymetric data. Meantime, this paper designs a set of multi-beam bathymetric real-time display and control software, combining with the research group multi-beam echo sounder. This thesis has mainly studied four problems:uncertainty propagation models, node estimation renew process, multiple estimatation alternative hypothesis process and display and control software.Firstly, the algorithm of automatic detection and elimination on outliers in this study is one of multibeam bathrmetry treatment technology. Through the study in principle and compose of multibeam bathymetric, correction of sound ray bending, and Beam foot Print Positionin, we can analyze the factors effected on horizontal and vertical uncertainty. Combined these factors, advisable horizontal and vertical uncertainty propagation models can be established. Then, used actual multibeam bathymetric data, the depth and uncertainty information of soundings are obtained.Secondly, Combined Bayesian theory, this thesis devides the porcess into three parts: assimilation, intervention, and disambiguation. To minus the effect of outliers on estimation result, grid node estimation is renewed through soundings sequence assimilation. Compare several typical alternative hypothesis criterions, gain merits and demerits of different criterions, then setup a minimum depth of the relative error criterion based on prior. When actual measurements have a large number of continuous outlier, robst estimatation measurements are obtained with the criterin above, which has high efficiency because of no search operations.Finally, this paper introduces processes and functions of the real-time multibeam bathymetric display and control software. This software is performance-complete and feature-rich. The paper designs seabed features integrated display and control detection software, extending the functionality of the real-time multi-beam bathymetric significant control software, adding seabed topography and shallow stratigraphic section display interface. Actual sea trials and data playback verify the stability of the integrated display and control software, timeliness and practicality. Has laid a good foundation for the study of outlier detection algorithm based CUBE multibeam practical application, laying a good foundation for the study of outlier detection algorithm based on CUBE multibeam practical application.