Using an Uncrewed Surface Vehicle to Create a Volumetric Model of Non-Navigable Rivers and Other Shallow Bodies of Water

TL;DR

This paper presents a practical method using an uncrewed surface vehicle to create detailed volumetric models of shallow water bodies by merging bathymetric and surface maps, aiding flood risk assessment.

Contribution

It introduces a novel approach combining sonar and visual data to generate unified volumetric models of non-navigable waters using an USV, addressing sensor coverage gaps.

Findings

Successful demonstration on Lake ESTI with USV and sensors.

Effective merging of bathymetric and surface meshes despite coverage gaps.

Potential for improved flood risk management and emergency planning.

Abstract

Non-navigable rivers and retention ponds play important roles in buffering communities from flooding, yet emergency planners often have no data as to the volume of water that they can carry before flooding the surrounding. This paper describes a practical approach for using an uncrewed marine surface vehicle (USV) to collect and merge bathymetric maps with digital surface maps of the banks of shallow bodies of water into a unified volumetric model. The below-waterline mesh is developed by applying the Poisson surface reconstruction algorithm to the sparse sonar depth readings of the underwater surface. Dense above-waterline meshes of the banks are created using commercial structure from motion (SfM) packages. Merging is challenging for many reasons, the most significant is gaps in sensor coverage, i.e., the USV cannot collect sonar depth data or visually see sandy beaches leading to a bank thus the two meshes may not intersect. The approach is demonstrated on a Hydronalix EMILY USV with a Humminbird single beam echosounder and Teledyne FLIR camera at Lake ESTI at the Texas A&M Engineering Extension Service Disaster City complex.