Mechanical Components

Molecular Engineering for Mechanically Resilient and Stretchable Electronic Polymers and Composites

The ability to predict the mechanical properties of organic semiconductors is of critical importance for roll-to-roll production and thermomechanical reliability of organic electronic devices. This research describes the use of coarse-grained molecular dynamics simulations to predict the density, tensile modulus, Poisson ratio, and glass transition temperature for poly(3-hexylthiophene) (P3HT) and its blend with C60. In particular, it is shown that the resolution of the coarse-grained model has a strong effect on the predicted properties.

Posted in: Briefs, Aerospace, Defense, Electronic Components, Electronics, Electronics & Computers, Composites, Materials, Mechanical Components, Semiconductors & ICs

Electrodeposition of Metal Matrix Composites and Materials Characterization for Thin-Film Solar Cells

The current trend in both space and terrestrial photovoltaics is to implement high-efficiency, thin-film-based solar cells to reduce weight and materials cost while improving performance. For space photovoltaics, multi-junction (MJ) solar cells have been used almost exclusively due to their high efficiency and high radiation hardness. The efficiency of state-of-practice triple-junction (TJ) cells used in space today is approximately 30% under 1-sun Air Mass 0 (AM0) spectrum.

Posted in: Briefs, Aerospace, Solar Power, Composites, Materials, Metals, Mechanical Components, Semiconductors & ICs

Waveform Synthesis for Shock Response Spectrum Replication, Applied to Ground Vehicle Component Testing

The motivation for this work is to mitigate shock levels on vehicle components, through testing new designs of equipment. The objective is to generate a time history to perform shock testing on military and commercial ground vehicle components. The time histories are used to drive hydraulic actuators coupled to a test specimen.

Posted in: Briefs, Aerospace, Defense, Power Management, Thermal Management, MEMs, RF & Microwave Electronics, Inspection Equipment, Instrumentation, Measuring Instruments, Monitoring, Test & Measurement, Testing Procedures

SnowMicroPenetrometer Applications for Winter Vehicle Mobility

The U.S. Engineer Research and Development Center (ERDC) Military Engineering Program on Remote Assessment of Infrastructure for Ensured Maneuver (RAFTER) Boreal Aspects of Ensured Maneuver (BAEM) identifies the need for modeling over-snow vehicle performance, as many factors related to vehicle setup and land surface condition contribute to vehicle efficiency. Accurately estimating snow macromechanical characteristics—such as elastic modulus, stiffness, and strength—is critical for understanding how effectively a vehicle will travel over snow-covered terrain.

Posted in: Briefs, Aerospace, Automotive, Mechanical Components, Inspection Equipment, Instrumentation, Measuring Instruments, Metrology, Monitoring, Test & Measurement, Testing Procedures, Automotive, Transportation

Hybrid Ultra-Low VOC and Non-HAP Rain Erosion Coatings

Numerous military aircraft and shipboard surfaces, such as radomes, antennas, gun shields, wing leading edges, and helicopter blade leading edges, are coated with a specialized erosion-resistant protective coating possessing strict performance requirements. These protective coatings must provide excellent rain erosion resistance, superior mechanical properties, good adhesion to the substrate and meet a host of other metrics outlined in MIL-PRF-32239 and SAE AMS-C- 83231A.

Posted in: Briefs, Aerospace, Defense, Coatings & Adhesives, Mechanical Components

Electrical Characterization of Crystalline UO2, THO2 and U0.71TH0.29O2

Tracking and identifying radiation sources in the age of nuclear proliferation and well- resourced non-state actors is a national priority. Current neutron detection methods favor large detector volumes and long data collection times. Additionally, portable neutron detection methods have persistent problems with low signal-to-noise (small pulse height) and require large applied voltages.

Posted in: Briefs, Aerospace, Defense, Materials, Mechanical Components, MEMs, Semiconductors & ICs, Data Acquisition, Detectors, Sensors

Matrix-Free Assisted Laser Desorption Ionization Using Metal-Organic Frameworks

Matrix-assisted laser desorption/ionization (MALDI) is a soft ionization technique that is widely applied in the characterization of large biomolecules using various mass spectrometry (MS) analyzers, specifically, time-of-flight (TOF) analyzers. The MALDI process involves the deposition of an analyte solution onto a metal substrate before the addition of a matrix. The matrix/analyte dry spot is exposed to a UV laser, and the laser energy that is absorbed by the matrix/analyte is converted into heat energy that initiates charge transfer, which results in the desorption of the matrix and analyte molecules in ionized form. The positive ions are then accelerated through a vacuum into MS analyses.

Posted in: Briefs, Aerospace, Defense, Materials, Metals, Mechanical Components, MEMs, Data Acquisition, Sensors, Inspection Equipment, Instrumentation, Measuring Instruments, Monitoring, Test & Measurement

Sound Attenuation of Neoprene Wetsuit Hoods as a Function of Dive Depth and Acoustic Frequency: Hyperbaric Chamber Trials

The U.S. Navy is interested in strategies that divers could employ to protect them from loud underwater sounds. Sonar transmissions and other forms of underwater sound, such as that produced by noisy underwater tools, are an occupational hazard for U.S. Navy divers.

Posted in: Briefs, Aerospace, Data Acquisition, Defense, Machinery, Mechanical Components, Data Acquisition, Measuring Instruments, Test & Measurement

Modular Biosensor Patch

Researchers are identifying new biomarkers to help monitor cognition and stress in the human body and enhance human performance. Traditional biomarkers like heart rate, temperature, oxygen partial pressure, blood glucose, electrolyte concentration, and others have been correlated with cognition and stress states. However, the correlation is indirect. Molecular biomarkers with stronger and more specific links are preferred.

Posted in: Briefs, Aerospace, Defense, Fluid Handling, MEMs, Medical, Patient Monitoring, Biosensors, Data Acquisition, Detectors, Sensors

Microstructural and Mechanical Characterization of 2-D and 3-D SiC/SiNC Ceramic-Matrix Composites

The purpose of this endeavor was to investigate the effect of 3-D weave architecture on PIP-processed ceramic-matrix composites (CMC). Microstructural studies were performed to document the resulting microstructure and mechanical testing was performed to determine the high-temperature durability of the five different variants of SiC/SiNC CMC investigated.

Posted in: Briefs, Aerospace, Imaging, Ceramics, Composites, Materials, Mechanical Components