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Method for accuracy assessment of topo-bathymetric surface models based on geospatial data recorded by UAV and USV vehicles

Lewicka Oktawia

Metrology and Measurement Systems

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2023

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Vol. 30, nr 3

461--480

EN

Geospatial data obtained using Unmanned Aerial Vehicles (UAVs) and Unmanned Surface Vehicles (USVs) are increasingly used to model the terrain in the coastal zone, in particular in shallow waterbodies (with a depth of up to 1 m). In order to generate a terrain relief, it is important to choose a method for modelling that will allow it to be accurately projected. Therefore, the aim of this article is to present a method for accuracy assessment of topo-bathymetric surface models based on geospatial data recorded by UAV and USV vehicles. Bathymetric and photogrammetric measurements were carried out on the waterbody adjacent to the public beach in Gdynia (Poland) in 2022 using a DJI Phantom 4 RTK UAV and an AutoDron USV. The geospatial data integration process was performed in the Surfer software. As a result, Digital Terrain Models (DTMs) in the coastal zone were developed using the following terrain modelling methods: Inverse Distance to a Power (IDP), Inverse Distance Weighted (IDW), kriging, the Modified Shepard’s Method (MSM) and Natural Neighbour Interpolation (NNI). The conducted study does not clearly indicate any of the methods, as the selection of the method is also affected by the visualization of the generated model. However, having compared the accuracy measures of the charts and models obtained, it was concluded that for this type of data, the kriging (linear model) method was the best. Very good results were also obtained for the NNI method. The lowest value of the Root Mean Square Error (RMSE) (0.030 m) and the lowest value of the Mean Absolute Error (MAE) (0.011 m) were noted for the GRID model interpolated with the kriging (linear model) method. Moreover, the NNI and kriging (linear model) methods obtained the highest coefficient of determination value (0.999). The NNI method has the lowest value of the R68 measure (0.009 m), while the lowest value of the R95 measure (0.033 m) was noted for the kriging (linear model) method.

2

A proposition of erosion algorithm for terrain models with hardness layer

Warszawski K. K., Nikiel S. S.

Journal of Theoretical and Applied Computer Science

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2014

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Vol. 8, nr 1

76--84

EN

Processes of erosion occurring in natural environment depend on two major factors. The first is the strength of erosion force, e.g. wind, rainfall or water flow. The second is the terrain hardness or its tolerance to erosion forces. In this article we propose a method of modelling terrain erosion process where the force is uniformly distributed over the entire model with local distribution of varying terrain sensitivity. For the simulations we use two-layered terrain model. The first layer contains information about heights distribution (height-field) and simulate topography of the terrain. The second layer stores data defining its hardness (hardness-field) that represents different geological structures in the terrain.

3

Modelling of terrain for necessities of military objects movement simulation

Tarapata Z.

Biuletyn Wojskowej Akademii Technicznej

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2000

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Vol. 49, nr 1

127-146

EN

A problem of terrain information gaining for objects movement simulation is considered. A mathematical model of terrain based on information from topographical map is presented. This model is used to constructing trafficable routes network (TRN). Two kinds of TRN, rough and precise, are considered. The first type of the network is based on the real roads in the terrain only. The precise network is constructed basing on partition of the terrain into squares of topographical homogeneous areas. A coding of this information is done by utilization of quadtrees. Examples of creating of TRN are shown.

PL

Rozpatrzono problem pozyskiwania informacji terenowej wykorzystywanej w algorytmach symulacji przemieszczania obiektów. Przedstawiono matematyczny model terenu bazujący na informacji z mapy topograficznej. Model ten wykorzystano na etapie konstrukcji sieci tras przejazdu. Zdefiniowano dwa rodzaje sieci tras przejazdu: zgrubną i dokładną. Pierwszy typ sieci oparto o rzeczywiste drogi istniejące w terenie. Sieć dokładna bazuje na podziale terenu na kwadraty obszarów jednorodnych topograficznie. Idea tego podziału została oparta o model drzewa czwórkowego. Zaproponowano przykłady wykorzystania przedstawionych modeli do tworzenia sieci tras przejazdu.