Electrical/​Electronics

Two modifications improve the performance of a circularly polarized microstrip-patch-array antenna described in U.S. Patent 5,661,994. Because the phase difference between the orthogonal sides in the original design was 135°, there was substantial cross-polarization and waste of power. One...

Direct methanol fuel cells integrated with fuel reservoirs have been proposed as power sources in applications that involve power demands up to about 50 W. A prior concept of direct methanol fuel cells as alternatives to re- chargeable batteries in such applications was reported previously in...

High-performance lithium-ion electro- chemical cells and batteries have been developed to satisfy a need for longer lifetimes and greater capacities in the power supplies of the life-support systems attached to space suits. These and similar cells and batteries could also be used on Earth to satisfy...

An electronic system based on long-wavelength infrared (LWIR) sensors is being developed to detect aircraft flying near an upward-aimed, high-power laser beam. In the intended application, the system would alert a human laser operator and/or generate a signal to turn off the laser whenever...

A class of optoelectronic noncontact computer-controlled scanning surface profilometers is undergoing development for use in automated or semiautomated in- spection of nominally flat surfaces. When fully developed, these profilometers would generate three-dimensional maps of the scanned surfaces for...

A system based on ultrasonic sensors has been developed as a means of tracking moving objects with centimeter accuracy. The system is intended especially for tracking pertinent parts of the body of a human subject engaged in control of a remote anthropomorphic robot or immersed in a...

An improved method of generating audible alarms has been invented for stressful environments in which there may be consid- erable background noise and where the intended recipients of the alarms also need to pay att- ention to sounds other than the alarms. An aircraft cockpit is a typical...

Connector test clamps (CTCs) are clamping electrical connectors designed for use in testing electrical continuity from the backshell of a connector at one end of a shielded electrical cable, through the cable shield, to the backshell at the other end of the cable. CTCs increase the reliability...

A method of automated evolutionary synthesis of electronic circuits has been augmented by a concept called “morphing through fuzzy topologies.” Previous versions of the method provided for the evaluation of “crisp” topologies were precisely specified by open/closed (on/off)...

Integrated silicon microdisplays, such as liquid-crystal-on-silicon (LCOS) devices, are becoming the most effective image source for high-resolution viewfinders, head- mounted displays, and helmet-mounted displays (HMDs). Since these microdisplays are reflective in nature, they require...

Human factors engineering has been applied to the design of an overheadbridge crane control console for use by a seated operator in a clean-room environment. The crane console provides the operator with the ability to lift and move loads up to 27.5 tons (24.9 tonnes) in three vertical speed ranges and three...

A relatively inexpensive, lightweight, durable, easy-to-operate radio-frequency (RF) instrument has been developed, along with special electromagnetic tags, for use in detecting buried objects to which the tags are attached. Each tag comprises a dipole antenna (basically, two collinear...

In a proposed method of designing a recon- figurable antenna, the design would be opt- imized through evolution in hardware. The proposed method would be a specific instance of an emerging general method of automated synthesis of electronic circuits in hardware. Other specific instances...

A test bench based on field-programmable gate arrays (FPGAs) has been developed to reduce the cost of testing nonvolatile memory circuits. Specifications for endurance testing of memories can require test times as long as weeks — often impractically long in the case of commercial memory...

A report discusses aspects of a ranging system in which the distance between the Earth and a spacecraft is determined from the difference between the phases of (1) modulation on a radio signal trans- mitted to the spacecraft and (2) a replica of the modulation transmitted back to Earth by a transponder on...