16 Jul 2024

Evaluation of the Version 1 Advanced Tactical Awareness Kit–Expeditionary Radar (ATAK-ER V1) for Accuracy and Reliability in Surf-Zone Characterization in a Range of Environmental Conditions

Abstract: This Coastal and Hydraulics Engineering Technical Note (CHETN) presents the evaluation of a rapidly deployable radar and associated software for characterizing surf-zone waves, currents, and bathymetries at the US Army Engineer Research and Development Center (ERDC), Coastal and Hydraulics Laboratory (CHL), Field Research Facility (FRF), in Duck, North Carolina. This project was conducted at the request of the US Marine Corps (USMC) Warfighting Laboratory. The Version 1 Advanced Tactical Awareness Kit–Radar Expeditionary (ATAK-ER V1) system was deployed 15 times between July and August 2023 to observe a range of wave, water level, and wind conditions that could each affect radar processing. Products from the system were then compared to the FRF’s continuously operating in situ instruments and monthly bathymetric surveys to quantify the accuracy and reliability of the output. A number of issues with the unit are identified, including potential error sources contributing to inaccuracies, but the black-box nature of the commercial off-the-shelf (COTS) unit prevents a confident understanding of why wave heights are underpredicted (by 65% on average), why bathymetries consistently have root-mean-square errors (RMSE) over 1 m with progressively greater errors with distance offshore, or why some collections are unable to generate all of the advertised products. This Version 1 COTS unit is not recommended for operational use at this time.

4 Oct 2023

Full-Scale Trafficability Testing of Prototype Submersible Matting Systems

Abstract: This report describes the full-scale evaluation of prototype submersible matting systems (SUBMAT) at a test site at the US Army Engineer Research and Development Center’s Vicksburg, Mississippi, site. The SUBMAT prototypes were designed to bridge the gap between high and low tide at a beach interface to enable 24-hour operation at an expeditionary watercraft landing site. This phase of the SUBMAT prototype development was intended to determine prototype system durability by applying military vehicle loads representing a combat brigade insertion across a littoral zone. The two mat systems evaluated in this study were the PYRACELL Road Building System (PRBS) and a basaltic rebar mat system. The results of the study showed that the PRBS system was able to sustain 1,000 Medium Tactical Vehicle Replacement, 350 Heavy Expanded Mobility Tactical Truck, and over 150 M1A1 main battle tank passes without significant damage. The basaltic rebar mat failed early in the test and was removed from further consideration for the SUBMAT application. Observations and lessons learned from this phase of the prototype PRBS development will be used to improve the PRBS design and modify its installation procedures for improved efficiency.