MEMs

Wettability Tests of Polymer Films and Fabrics

High-strength polymer materials are useful components in many multifunctional materials applications. However, because of low reactivity, their use is inhibited in many processing techniques. Polymer films and fibers possess low surface energies and need to be modified through surface activation prior to being used in composite systems where adhesive bonding is an issue. Treatment of polymer materials through plasma processing is one route to greatly increase surface reactivity. Once the surface has been plasma-modified, wettability by liquids can be examined to determine the treatment effects on the polymer material’s surface reactivity.

Posted in: Briefs, Materials, Joining, Composite materials, Fibers, Materials properties, Polymers
Read More >>

Using a Steering Shaping Function to Improve Human Performance in By-Wire Vehicles

Currently, there is a performance issue regarding vehicle control at higher speeds for some indirect-vision, by-wire military vehicles; that is, those vehicles in which mechanical links between the driver and control devices are replaced by electronic or computerized signals. Work has been performed to assess the current state of knowledge regarding the shaping function. The overall goal was to identify design parameters critical to improving the current by-wire implementation for military tactical vehicles, and to ultimately optimize system (i.e., human-vehicle) performance for the execution of secure mobile operations.

Posted in: Briefs, Mechanical Components, Steer-by-wire, Human machine interface (HMI), Military vehicles and equipment, Vehicle dynamics
Read More >>

Manufacturing Cylindrical Parts Using Deep Draw Technology

In applications where product performance is mission critical, commercial, military, and aerospace companies require technology to manufacture deep- drawn cylindrical product components. Conventional production alternatives such as impact, spinning, and supplemental annealing processes often do not deliver reliable results for certain applications.

Posted in: Briefs, Manufacturing & Prototyping, Molding, Production engineering, Parts
Read More >>

Advanced Lithium Ion Systems for Military Vehicles

The higher energy and power density of Li-Ion battery technology offers a significant reduction in the weight and volume for hybrid electric vehicle (HEV) battery systems compared to lead acid and nickel metal hydride technologies. Saft’s High Power Li-ion battery technology has demonstrated specific power of over 6,000 W/kg under continuous discharge, and a pulse discharge of 8,000 to 12,000 W/kg.

Posted in: Briefs, Physical Sciences, Lithium-ion batteries, Hybrid electric vehicles, Military vehicles and equipment
Read More >>

MEMS-Based Optical Limiter

Protecting optical sensors and detectors against excessive input signals is not only important for dealing with unintentional overloads, but also central for protecting sensors against intentional high-intensity sources such as flares or laser beams directed as countermeasures against the sensor system. In prior work, a microelectromechanical system (MEMS)-based, all optically driven deformable mirror was designed and fabricated. In this work, an optical limiter using this optically addressed, deformable mirror is proposed and designed.

Posted in: Briefs, Physical Sciences, Mirrors, Microelectricmechanical device, Optics, Sensors and actuators
Read More >>

Reducing Thicknesses of PbZrₓTi₁₋ₓO₃ Films in Capacitors

A document describes experiments performed to determine effects of reducing the thicknesses of films of lead zirconate titanate (PbZrxTi1-xO3, wherein 0<x<1) used as ferroelectric dielectric layers in some capacitors. The fabrication of specimen capacitors for the experiments involved numerous steps, including spin-coating of PbZrxTi1-xO3-precursor sol-gel solutions onto bottom Pt electrode layers on silicon substrates, heat treatments to covert the sol-gel coats to PbZrxTi1-xO3, and deposition of top Pt electrode layers on the PbZrxTi1-xO3 layers. Various spin rates and solution compositions were used to obtain various PbZrxTi1-xO3- film thicknesses and compositions. Current responses of specimens to applied voltage waveforms were measured to characterize the specimens in terms of capacitance, hysteresis, and polarization. It was concluded that thicknesses of PbZrxTi1-xO3 films could be reduced to between 1,800 and 2,200 A while retaining ferroelectric performance adequate for a proposed development in which nanoelectromechanical switches containing PbZrxTi1-xO3 films would be integrated with complementary metal oxide/semiconductor transistors. One of the sol-gel solutions, characterized by x = 0.45 and a molarity of 0.367, was found to be the most promising for further work to improve performance at thicknesses < 1,800 A.

Posted in: Briefs, Physical Sciences, Capacitors, Transistors, Fabrication, Ferrous metals and alloys, Silicon alloys
Read More >>

Virtual Network Computing Software for DataWall Remote Display

VNC (Virtual Network Computing) is open-source software that allows a user to view and interact with a remote computer (known as the VNC server) from a local computer (known as the VNC viewer/client). VNC is used to display multiple remote desktops on the DataWall. The original VNC software can only project the whole desktop from a server to the DataWall. The VNC server and viewer were modified to project the whole desktop or an application of interest from a server to the DataWall.

Posted in: Briefs, Software, Computer software / hardware, Data exchange, Human machine interface (HMI), Displays
Read More >>

Software Suite for a Large Defense System

A suite of software tools was developed to enable networks composed of many hundreds, thousands, or even millions of commodity computers to protect themselves against a variety of security threats. These tools include Anagram, a content-based anomaly detection (AD) tool; ASSURE, which provides automatic software self-healing; and Aeolos, a distributed intrusion detection and event correlation infrastructure.

Posted in: Briefs, Software, Computer software / hardware, Cyber security, Neural networks
Read More >>

OpenVPX

For 25 years, the VME architecture defined COTS systems that met the demand for increases in computing and connectivity. Successive generations of new processors provided more and more compute cycles, while VME bandwidth evolved in a similar fashion from 40 Mbytes/s on the original VMEbus to 80 Mbytes/s, then 160 Mbytes/s and finally 320 Mbytes/s on 2eSST.

Posted in: Articles, Articles, Electronics & Computers, Architecture, Computer software / hardware, Data exchange, Technical reference
Read More >>

Secure Software Flashing

More and more devices in our modern world come with a multitude and variety of embedded systems. An obvious example of this trend is today’s vehicles, which have dozens of electronic control units (ECUs) that control everything from the air conditioning and electric windows to the engine and brake system. Several ECUs allow downloading of updated program and data code via a boot loader. Such software might be a control unit firmware update for fixing bugs, for improving features, or for downloading data such as additional multimedia files. The first case is also called a software download or simply flashing (since flash memory is updated). The download might be performed directly over a diagnostic channel or another available communication channel such as Bluetooth and GSM.

Posted in: Articles, Articles, Electronics & Computers, Cyber security, Electronic control units, Embedded software, Vehicle networking, Maintenance, Repair and Service Operations
Read More >>