12 May 2021

Methodology for Remote Assessment of Pavement Distresses from Point Cloud Analysis

Abstract: The ability to remotely assess road and airfield pavement condition is critical to dynamic basing, contingency deployment, convoy entry and sustainment, and post-attack reconnaissance. Current Army processes to evaluate surface condition are time-consuming and require Soldier presence. Recent developments in the area of photogrammetry and light detection and ranging (LiDAR) enable rapid generation of three-dimensional point cloud models of the pavement surface. Point clouds were generated from data collected on a series of asphalt, concrete, and unsurfaced pavements using ground- and aerial-based sensors. ERDC-developed algorithms automatically discretize the pavement surface into cross- and grid-based sections to identify physical surface distresses such as depressions, ruts, and cracks. Depressions can be sized from the point-to-point distances bounding each depression, and surface roughness is determined based on the point heights along a given cross section. Noted distresses are exported to a distress map file containing only the distress points and their locations for later visualization and quality control along with classification and quantification. Further research and automation into point cloud analysis is ongoing with the goal of enabling Soldiers with limited training the capability to rapidly assess pavement surface condition from a remote platform.

12 May 2021

Channel Assessment Tools for Rapid Watershed Assessment

Purpose: Existing Delta Headwaters Project (DHP) watershed stabilization studies are focused on restoration and stabilization of degraded stream systems. The original watershed studies formerly under the Demonstration Erosion Control (DEC) Project started in the mid 1980s. The watershed stabilization activities are continuing, and because of the vast number of degraded watersheds and limited amount of yearly funding, there is a need for developing a rapid watershed assessment approach to determine which watersheds to prioritize for further work. The goal of this project is to test the FluvialGeomorph (FG) toolkit to determine if the Rapid Geomorphic Assessment approach can identify channel stability trends in Campbell Creek and its main tributary. The FG toolkit (Haring et al. 2019; Haring et al. 2020) is a new rapid watershed assessment approach using high-resolution terrain data (Light Detection and Ranging [LiDAR]) to support U.S. Army Corps of Engineers (USACE) watershed planning. One of the principal goals of the USACE SMART (Specific Measureable Attainable Risk-Informed Timely) Planning is to leverage existing data and resources to complete studies. The FG approach uses existing LiDAR to rapidly assess either reach-specific analysis for smaller more focused studies or larger watersheds or ecosystems. The rapid assessment capability can reduce the time and cost of planning by using existing information to complete a preliminary watershed assessment and provide rapid results regarding where to focus more detailed study efforts.

4 May 2021

First Generation Automated Assessment of Airfield Damage from LiDAR Point Clouds

Abstract: This research developed an automated software technique for identifying type, size, and location of man-made airfield damage including craters, spalls, and camouflets from a digitized three-dimensional point cloud of the airfield surface. Point clouds were initially generated from Light Detection and Ranging (LiDAR) sensors mounted on elevated lifts to simulate aerial data collection and, later, an actual unmanned aerial system. LiDAR data provided a high-resolution, globally positioned, and dimensionally scaled point cloud exported in a LAS file format that was automatically retrieved and processed using volumetric detection algorithms developed in the MATLAB software environment. Developed MATLAB algorithms used a three-stage filling technique to identify the boundaries of craters first, then spalls, then camouflets, and scaled their sizes based on the greatest pointwise extents. All pavement damages and their locations were saved as shapefiles and uploaded into the GeoExPT processing environment for visualization and quality control. This technique requires no user input between data collection and GeoExPT visualization, allowing for a completely automated software analysis with all filters and data processing hidden from the user.

1 Sep 2020

PUBLICATION NOTICE: Sensor and Environment Physics in the Virtual Autonomous Navigation Environment (VANE)

Abstract: This report documents the physics models that are implemented in the Virtual Autonomous Navigation Environment (VANE), a sensor simulator that uses physics-based ray tracing to simulate common robotic sensors such as cameras, LiDAR, GPS, and automotive RADAR. The report will provide information about the underlying assumptions and implementation details regarding the physics models used in VANE simulations. These include surface reflectance and texture models, atmospheric models, weather effects, and sensor properties. The purpose of this report is to provide information for VANE users, developers, and analysts who would like to use the VANE for sensor simulations.

20 Aug 2020

PUBLICATION NOTICE: Evaluating Collection Parameters for Mobile Lidar Surveys in Vegetated Beach-Dune Settings

Purpose: The goal of this Coastal and Hydraulics Engineering Technical Note (CHETN) is to compare collection parameters and gridding techniques for mobile lidar surveys of beach-dune systems in the northern Outer Banks, NC.

25 Jun 2020

PUBLICATION NOTICE: Rapid Watershed Assessment Tools Based on High-Resolution Terrain Data

Abstract: The goal of this project was to develop rapid watershed assessment methods to estimate channel stability and sediment transport potential using high resolution terrain data (Light Detection and Ranging-LiDAR) to support US Army Corps of Engineers (USACE) watershed planning. This project developed a suite of tools based on advanced remote sensing technologies (LiDAR) that use off-the-shelf, high-resolution terrain data to rapidly assess watershed condition at the channel, floodplain, valley, and watershed scales. The widespread availability of high-resolution terrain data provides an opportunity to assess watershed conditions in great detail over large spatial extents. For this project, a channel assessment method was developed using a new LiDAR Hydraulic Geometry Relationships (HGR)-based approach for developing regional curves.

30 Apr 2020

PUBLICATION NOTICE: Seamless Integration of Lidar-Derived Volumes and Geomorphic Features into the Sediment Budget Analysis System

Abstract: This Regional Sediment Management Technical Note provides a workflow and case study documenting the process to integrate lidar-derived volume changes and changes quantified from geomorphic features into the Sediment Budget Analysis System. Sediment budgets provide an understanding of a region’s sediment sources, project needs, processes, data gaps, engineering actions, and ecological considerations. Elevation data from profiles or lidar, sediment characteristics, dredging and placement information, along with other coastal datasets, are used to understand sediment pathways and develop sediment budgets for a region. Workflows and tools have been updated or modified to integrate sediment budget tools, volume change tools, and remote sensing data for the creation of comprehensive regional sediment budgets. 

14 Apr 2020

PUBLICATION NOTIFICATION: Coincidence Processing of Photon-Sensitive Mapping Lidar Data

 Link: http://dx.doi.org/10.21079/11681/35599 Report Number: ERDC/GRL TR-20-1Title: Coincidence Processing of Photon-Sensitive Mapping Lidar DataBy Christian Marchant, Ryan Kirkpatrick, and David OberApproved for Public Release; Distribution is Unlimited February 2020Abstract: Photon-sensitive mapping lidar systems are able to image at greater

15 Jan 2020

PUBLICATION NOTICE: An Airborne Lidar Point Cloud-based Below-Canopy Line-of-Sight Visibility Estimator

 Link: http://dx.doi.org/10.21079/11681/35175Report Number: ERDC/GRL MP-20-1Title: An Airborne Lidar Point Cloud-based Below-Canopy Line-of-Sight Visibility EstimatorBy Heezin Lee, S. Bruce Blundell, Michael J. Starek, and John G. HarrisApproved for Public Release; Distribution is Unlimited January 2020Abstract:  Point cloud data collected by