Application exploration of optical remote sensing technology of unmanned aerial vehicle in measuring bulk trade at sea

Abstract

The method of measuring the weight of cargo with draft gauge is a general method for bulk cargo measurement at sea. However, this method of measuring the draft line value by human eyes is often subjective and has great limitations.At the same time, due to the manufacturing error of the ship, the production deviation of the completion drawing and the correction chart, as well as the influence of the ship deformation, material preparation change, wind wave, hydrology and other factors, the actual accuracy of the draft gauge weight measurement is difficult to guarantee.In this paper, a new method of bulk cargo trade measurement is proposed. Firstly, the UAV is equipped with multi lens camera, and the images before and after unloading are obtained by optical remote sensing technology. Then, according to the highprecision phase control point coordinates of the ship, the whole adjustment of the regional network is carried out by using the beam method to realize the automatic aerial triangulation Dense matching algorithm, automatically matching all the same points in the image, so as to get a large number of 3D point cloud data. Finally, the Irregular Triangulation model of ship hull is constructed by dealunay triangulation methodand.The ship's three-dimensional contour is fitted, and the hull is divided into several sections along the height direction, and the displacement difference before and after unloading is calculated, so as to calculate the ship unloading value. This method can reduce manual measurement error and ship draft error, and improve the accuracy of bulk cargo measurement. It is expected to become a new measurement method for bulk cargo trade.