Multibeam Bathymetric Data Quality Control based on Robust Least Square Collocation of Improved Multi - quadric Function

Abstract

Abnormal value of the multibeam echosounder system is the main influencing factor of accuracy of hydrographic survey and mapping accuracy of seabed topography. Good functional and stochastic models for multibeam bathymetric data processing are necessary to protect accurate display of multibeam bathymetric data in seabed and safety navigation of ships. This study proposed a robust least square collocation method based on the improved multi-quadric function to represent the variation trend of seabed topography accurately and disclose the real seabed topography along with the systematic and random problems of nonsteady multibeam bathymetric data of seabed topography. Fitting methods of seabed topography trend surface and the elimination of trend items were analyzed. The solving method of the empirical covariance function in the least square collocation and the method to eliminate abnormal values in multibeam bathymetric data were proposed. Validity of the proposed method was proved by an experiment. Results demonstrate that the fitted trend terms in the improved multi-quadric function can reflect the overall trend changes of the study area effectively. The applied robust least square collocation method can effectively reflect the systematicness and randomness of nonsteady bathymetric data of seabed topography. This method can overcome the influences of gross errors or abnormal points on the multibeam bathymetric data and can thus increase the accuracy of the estimation points. Compared with the traditional quadratic polynomial surface fitting method, the proposed method is superior in reflecting the overall trend changes in seabed topography, quality of multibeam bathymetric data, and mapping accuracy of seabed topography. This study can increase the detection capacity and effects of seabed topography at a high working efficiency and lay foundations for scientific research and marine exploration in the future.

A Review of Data Cleaning Approaches in a Hydrographic Framework with a Focus on Bathymetric Multibeam Echosounder Datasets

“…Among the remaining, five [4,16,17,31,32] of them rely on the DBM method and only two apply a combined validation method [27,33]. Whereas surface-oriented algorithms are mostly assessed using visual inspection methods followed by cross-reference to previous surveys (i.e., 4 articles [3,40,42,56]) visual inspection methods only (i.e., 5 articles [30,34,37,41,55]) or the DBM method (i.e., 4 articles [18,26,52,53]). To address effective performance evaluations, (i) local visual inspections through data points enhanced through statistical information and (ii) a global overview of the survey through the creation of a DBM, should be provided.…”

“…However, native SVM approaches are known to have a high computational cost. Wang ( [26,52]) proposes heuristics algorithms aiming at working through a reduced set of support vector machines, still using radial basis kernels and robust metrics.…”

The State of the Hydrographic Survey and Assessment of the Potentially Risky Region for Navigation Safety

“…The importance of accurate bathymetric and hydrographic data is recognized. The authors of [14][15][16][17][18][19] proposed and analyzed methods and algorithms that will make it easier to recognize the data obtained by using multi-beam echosounder datasets. Onwards, new correction methods were researched and proposed to obtain data using air and satellite platforms [20][21][22][23][24][25].…”