Special Coverage


Improving Material Property Measurement Using Multi- Camera Digital Image Correlation

The automotive industry faces growing pressure for more efficient vehicles. This pressure comes from many sources including government regulations, decreasing natural resources, and consumer demand. As the pressure begins to rise, automakers have a growing need for better fuel, more efficient energy-generating processes, and lighter vehicles. In an effort to reduce the weight of their vehicles, automakers have shown an increasing interest in using aluminum, provided it can withstand the same deformations as steel.

Posted in: Materials, Briefs


Mechanistic-Based Multiaxial- Stochastic-Strength Model for Transversely- Isotropic Brittle Materials

The methodology is applicable to a wide variety of graphite, coatings, and composite materials. A methodology has been developed and the software written to predict the probability of failure of transversely isotropic (a type of anisotropy) materials under generalized thermomechanical loading. This methodology is mechanistic in that it is based on the physical characteristics of brittle fracture, and morphological in that it considers the size, shape, and orientation distribution of strength controlling defects or flaws. On that basis, it can also account for a material’s failure modes and direction of damage initiation from loading. It is capable of predicting an anisotropic material’s probability of failure under transient and cyclic loading. This innovation can be applied to materials such as graphite, coatings, or the individual brittle constituents of composite materials.

Posted in: Materials, Briefs


Video Routing System Upgrades Mission Control Center

PESA has announced the completion of a video routing system upgrade to NASA’s Mission Control Center (MCC) at the agency’s Johnson Space Center (JSC) in Houston. Lockheed Martin, a prime contractor for NASA, commissioned PESA to provide hardware and system training for its Cheetah Video Distribution System (VDS).

Posted in: Application Briefs


Product of the Month: The APN Series Power Monitoring Sensor

NK Technologies, San Jose, CA, has introduced the APN Series power monitoring sensor that measures three phases of current and voltage, and computes 14 values necessary to track power usage in the RS-485 Modbus RTU format. The monitor uses current transformers to measure the amperes. The line voltage connects directly to the transducer, up to 600 VAC. The unit’s RS-485 Modbus RTU format is compatible with many programmable logic controllers, and fits into industrial communications networks, both hard-wired and wireless, depending on the application. It can be configured to accept standard 5-amp current transformer inputs or sensors producing 333 mVAC proportional to the AC current of the circuit. The primary circuit voltage is connected directly to the monitor for 600 VAC or lower, or through a potential transformer for monitoring circuits of higher potentials. The APN is powered from an external supply, and provides a pulse contact to open and close as Watt hours are accumulated.

Posted in: Products


Collaborative Platforms Aid Emergency Decision-Making

Real-time data from NASA satellites enables public agencies to better prepare for natural and manmade disasters. NASA runs and partners in many missions dedicated to monitoring the Earth, and the tools used in these missions continuously return data on everything from shifts in temperature, to cloud formation, to pollution levels over highways. The data are of great scientific value, but they also provide information that can play a critical role in decision-making during times of crisis. Real-time developments in weather, wind, ocean currents, and numerous other conditions can have a significant impact on the way disasters unfold.

Posted in: Articles


Dual-Leadframe Transient Liquid Phase Bonded Power Semiconductor Module Assembly and Bonding Process

This module package and bonding process enable device operation at temperatures exceeding 400 °C. A high-temperature-capable widebandgap semiconductor power module package, coupled with a new high-temperature- capable bonding process (with an optimized assembly and manufacturing process), has been developed that, together, can allow device operation at temperatures exceeding 400 °C, with the potential for higher-temperature operation depending on the semiconductor device characteristics. The semiconductor module is an ultracompact, hybrid power module that uses double leadframes and direct lead-frame-to- chip transient liquid phase (TLP) bonding. The unique advantages include very high current-carrying capability, low package parasitic impedance, low thermomechanical stress at high temperatures, double-side cooling, and modularity for easy system-level integration. The new power module will have a very small form factor with 3 to 5× reduction in size and weight from the prior art, no failure-prone bond wires, and will be capable of operating from 450 to –125 °C.

Posted in: Electronics & Computers, Semiconductors & ICs, Briefs


Methods for Mitigating Space Radiation Effects, Fault Detection and Correction, and Processing Sensor Data

A combination of three innovations enables increased efficiency, stability, and flexibility of data management and systems functionality. The Integrated Modular Avionics (IMA) architecture being developed for space applications requires that sensor data be autonomously sampled and transmitted to the system network. This transmission needs to occur on a predetermined, fixed schedule to avoid conflicts on the network. It needs to be capable of building packets of sensor data for individual application partitions (i.e., environmental control, propulsion, and vehicle management). It must be easily configured for flexibility in system scheduling.

Posted in: Electronics & Computers, Briefs