MEMs

Improvements in Manufacturing BMI/Fiber Composites Using AFP

A program now in progress is dedicated to making improvements in automated fiber placement (AFP) for the manufacture of advanced composite-material (matrix/fiber) structural components — especially skin and shell components for aircraft. [In AFP, a composite-material part is formed by laying down fiber tow or tape pre-impregnated with a matrix resin (“prepreg”) onto a mandrel that defines the shape of the part.] Improvements are sought for the following reasons:

Posted in: Briefs, Manufacturing & Prototyping
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Patterning of Polycrystalline Bi2Te3 Thin Films on Silicon

Experiments in patterning of thin films of polycrystalline bismuth telluride (Bi2Te3) on silicon substrates have been performed. Bi2Te3 is representative of a family of thermoelectric materials that are well suited for use in extracting electric energy from thermal gradients associated with flows of waste heat at temperatures in the approximate range of 0 to 150°C. Techniques and processes for fabricating macroscopic thermoelectric devices from bulk thermoelectric materials are mature and well known, but the same cannot yet be said concerning the fabrication of microscopic thermoelectric devices. The experiments reported here were performed as part of a continuing effort to develop capabilities for fabrication (including mass production) of microscopic thermoelectric devices, with a view toward eventually enabling the incorporation of them as integral parts of micro-electromechanical systems (MEMS) that could also include heat exchangers, sensors, actuators, and/or flow channels. Thus, the development of microscopic thermoelectric devices could benefit from the established industrial infrastructure for manufacturing MEMS and other silicon-based microsystems.

Posted in: Briefs, Manufacturing & Prototyping
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Tactical Medical Coordination System

The term "tactical medical coordination system" (TacMedCS) denotes any of several prototype electronic systems for tracking patients in a scenario that may involve multiple instances of treatment by different medical personnel in different locations. The TacMedCS was conceived as a means of facilitating coordination of care of military personnel injured in combat and/or facilitating coordination of care of victims of large-scale disasters. The most advanced prototype has already been demonstrated to be effective in operations at a Navy fleet hospital.

Posted in: Briefs, Medical
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Remote Blood Pressure Waveform Sensing

This non-contact, non-invasive blood pressure apparatus continuously measures and monitors blood pressure using a laser Doppler vibrometer to create waveforms. The laser-based system may be utilized to continuously provide highly detailed information about the timing characteristics of the blood pressure waveform. The system does not require elaborate adjustments of one or more lasers and laser detectors so it may be quickly utilized. The system takes measurements from a subject when the subject is moving.

Posted in: Briefs, Medical
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Robot Vision System for Precise Object Retrieval in Unmanned Systems

Automating large-scale material handling systems that involve picking up or retrieving items via cranes or robot arms can yield big benefits, particularly in harsh or hard-to-access environments. The Automatic Launch & Recovery System (AutoLARS) is being developed for the U.S. Navy by Allied Systems and Concept Systems. The Navy required a system for retrieving unmanned vessels and placing them aboard Navy ships. The problem is how to guide a robot that is affixed to a ship so that it can attach a line or fixture to an unmanned floating vehicle, and how to accomplish this while both are tossing at sea.

Posted in: Briefs, Physical Sciences
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Advanced Concepts for Space Access

A paper summarizes commonly proposed advanced launch concepts, including both concepts that employ propellant and propellant-less concepts. A wide range of advanced launch concepts have been proposed in an effort to revolutionize space access through either a significant reduction in launch costs or significant improvements in launch performance. These revolutionary concepts aren't necessarily required to be in the propulsion arena. For example, materials that can dramatically reduce the inert mass fraction will also aid in a launch vehicle's ability to place more payload into orbit with existing propulsion systems.

Posted in: Briefs, Physical Sciences
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Explicitly Timed Authorization Logic

A document describes explicitly timed authorization logic (nicknamed "η-logic"). In prior authorization logics, it is, variously, impossible or difficult to handle time explicitly; express security policies that involve complex, time-dependent relationships; or reason accurately about time. By enabling explicit mention of time, η-logic makes it easier to reason about time-dependent consequences of policies.

Posted in: Briefs, Information Technology
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Emerging Power and Energy Technologies for Portable Electronics

A report discusses data obtained for the Navy's Special Operations Command (SOCOM), which seeks a portable power/energy source capable of providing sufficient power and energy for complex missions at a minimal weight penalty. The report focuses on the specific energy of systems, defining the weight of the power/energy system that must be carried by the soldier.

Posted in: Briefs, Electronics & Computers
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Using RFID to Protect System Firmware

Breeching the security of safety- or security-intensive products such as auto parts, set top boxes, military electronics, or smart batteries can be a lucrative business that is well worth the nominal investment required to create lookalike packaging and labeling, or to change the system firmware to allow unpaid access to licensed content. Because the counterfeiter does not incur any of the costs associated with product development, he quickly covers his capital investment at the expense of the authentic product manufacturer or service provider.

Posted in: Articles, Articles, Electronics & Computers, Computer software / hardware, Cyber security, Radio-frequency identification
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Board Versus Box: The Age-Old DAQ Dilemma

Since the beginning of PC-based data acquisition and control in the 1980s, one question has remained a constant consideration for all who would specify a new DAQ system. Is this application better served by an external I/O "box" connected to the PC via some communications link, or an internal "board" system plugged into a slot within the computer? If anything, this question has become more complicated as technology has progressed.

Posted in: Articles, Articles, Board-Level Electronics, Electronics & Computers, Architecture, Computer software / hardware, Integrated circuits, Technical reference
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