Tech Briefs

Lipid Layer-Based Corrosion Monitoring on Metal Substrates

Corrosion is a deforming process that costs the United States Department of Defense (DOD) approximately $23 billion annually and accounts for 23% of all DOD maintenance. Exhaustive efforts have been made towards the detection and diagnosis of this issue; however, the problem persists. The Army’s “Go Green” initiative has opened the door for research into an environmentally friendly, biologically based corrosion monitoring technique. For this reason, novel research is being conducted on the use of lipid layers in corrosion monitoring.

Posted in: Briefs, Materials, Corrosion, Metals

Confocal Imaging System for Ultra-Fast, Three-Dimensional Transport Studies in Thermal Management Applications

The objective of this work was to develop a high-speed, three-dimensional (3D) confocal imaging system to study coupled fluidic and heat transport processes for high-performance thermal management applications. However, to successfully implement these approaches, fundamental understanding of interfacial dynamics and transport processes was necessary.

Posted in: Briefs, Physical Sciences, Imaging, Thermal management

Evaluating a Data Clustering Approach for Lifecycle Facility Control

Given the current emphasis on sustainability, there is a growing interest in monitoring various facets of building resource consumption. Building monitoring and automation systems most commonly exist as closed-loop systems for security, fire safety, water, electrical, and HVAC (Heating, Ventilation, and Air-Conditioning). One of the fundamental requirements of a mature engineering process model is the comparison of planned versus actual results for cost, risk, and quality control. For facility engineering, this implies that there must be a structured specification of building space requirements and a mechanism for detecting divergent system and occupant behaviors. Such a mechanism would have broad applicability for commissioning, energy efficiency, sustainability, diagnostics, maintenance, and a variety of other problems.

Posted in: Briefs, Physical Sciences, Sustainable development, Cost analysis, Risk management, Total life cycle management, Quality control

Portable Data Recorder for Measuring Sand Grain Fracture After Blasts

Abullet cannot penetrate through a sandbag while an arrow can, so understanding the behavior of granular materials such as sand and its energy absorption in a blast is critical in the design of armor. To this end, as part of the “Soil Blast Modeling and Simulations” project sponsored by the Office of Naval Research’s Multidisciplinary University Research Initiative (MURI), experiments were performed using a portable data recorder to determine the mechanical behavior of sand grains under confined compression.

Posted in: Briefs, Physical Sciences, Particulate matter (PM), Soils, Materials properties, Event data recorders, Military vehicles and equipment

Effect of Acceleration Frequency on Spatial Orientation Mechanisms

Extreme motion environments can induce loss of visual acuity, motion sickness, and spatial disorientation. Understanding how human sensory integration of acceleration stimuli affects spatial awareness will improve models of spatial disorientation and mishap analysis. While there are numerous studies describing vestibular semicircular canal responses to angular acceleration, less is known about vestibular otolith responses to linear acceleration. This gap in knowledge is important to resolve, since seasickness and airsickness are highly dependent on the predominant frequency of a linear acceleration stimulus.

Posted in: Briefs, Medical, Body regions, Human factors, Nervous system, Vehicle acceleration, Vehicle dynamics

Localization of Head-Mounted Vibrotactile Transducers

T he human sensory systems most frequently used in military displays (vision and audition) are sometimes overloaded. When soldiers rely on visual or auditory displays, their situation awareness can be degraded due to the need to attend to the display. A proposed alternative sensory channel for soldier displays is the tactile channel. In military applications, VT displays are primarily being used to aid in orientation, navigation, and communication. Tactile displays can also be used to impart more abstract information such as in command-and-control applications.

Posted in: Briefs, Physical Sciences, Displays, Vibration, Helmets, Military vehicles and equipment

High-Resolution, Measurement-Based, Phase-Resolved Prediction of Ocean Wavefields

Given remote and direct physical measurements of a realistic ocean wavefield, the goal of this work was to obtain a high-resolution description of the wavefield by integrating the measurements with phase-resolved wave prediction models including realistic environmental effects such as wind forcing and wave breaking dissipation. The measurements necessary for achieving this reconstruction were guided, and the validity, accuracy, and limitations of such wavefield reconstructions were addressed.

Posted in: Briefs, Physical Sciences, Measurements, Simulation and modeling, Water