May 2003

Features: Photonics/Optics
Advanced Near-Infrared Cameras

Many imaging applications in the near-infrared (NIR) region of the spectrum require sensors that see beyond the traditional charge-coupled device (CCD) sensor’s spectral range. A standard uncoated CCD...

Briefs: Information Technology
Developing Generic Software for Spacecraft Avionics

A proposed approach to the development of software for spacecraft avionics is based partly on a concept of generic software that could be tailored to satisfy requirements for specific missions. The proposed approach would stand in contrast to the conventional approach of first defining avionics...

A set of special digital all-pass finite- impulse- response (FIR) filters produces phase shifts equivalent to delays that equal fractions of the sampling or clock period of a...

Briefs: Physical Sciences
Assessment of Models of Chemically Reacting Granular Flows

A report presents an assessment of a general mathematical model of dense, chemically reacting granular flows like those in fluidized beds used to pyrolize biomass. The model incorporates submodels that have been described in several NASA Tech Briefs articles, including "Generalized...

Briefs: Physical Sciences
Numerical Study of Pyrolysis of Biomass in Fluidized Beds

A report presents a numerical-simulation study of pyrolysis of biomass in fluidized-bed reactors, performed by use of the mathematical model described in "Model of Fluidized Bed Containing Reacting Solids and Gases" (NPO-30163), which appears elsewhere in this issue of NASA Tech Briefs....

The figure depicts an example of proposed compact water-quality sensors that would contain integrated arrays of ion-sensitive electrodes (ISEs). These sensors would serve as electronic...

A mathematical model has been developed for describing the thermofluid dynamics of a dense, chemically reacting mixture of solid particles and gases. As used here, "dense"...

A technique for the fabrication of piezoelectric actuators that generate acceptably large forces and deflections at relatively low applied voltages involves the stacking and diffusion...

Experiments have shown that superlattices that comprise alternating epitaxial layers of dissimilar paraelectric perovskites can exhibit large changes in permittivity with the application...

Briefs: Electronics & Computers
Wireless Temperature-Monitoring System

A relatively inexpensive instrumentation system that includes units that are connected to thermocouples and that are parts of a radio-communication network has been developed to enable monitoring of...

Very-large-scale integrated (VLSI) analog binaural signal-processing circuits have been proposed for use in detecting and locating leaks that emit noise in the ultrasonic frequency...

The cascade back-propagation (CBP) algorithm is the basis of a conceptual design for accelerating learning in artificial neural networks. The neural networks would be implemented as analog...

A number of display systems primarily used in specialized areas such as aviation, space (NASA), and military/defense employ non-standard video signal...

Briefs: Mechanical & Fluid Systems
Bio-Inspired Engineering of Exploration Systems

The multidisciplinary concept of " b ioinspired e ngineering of e xploration s ystems" (BEES) is described, which is a guiding principle of the continuing effort to develop biomorphic...

An improved method of fabrication of cathodes of microbatteries is based on electrophoretic deposition. Heretofore, sputtering (for deposition) and the use of photoresist and liftoff...

An improved design for multiple-well microscope cells and an associated improved method of fabricating them have been devised. [As used here, "well" denotes a cavity that has...

Manufacturing companies must bring high-quality products to market faster than ever before. This tightened timeframe significantly impacts the manufacturing supply chain — a familiar...

Briefs: Manufacturing & Prototyping
Wheel Design Verified With FEA Software

This paper examines an aluminum wheel design used with a run-flat tire called an extended mobility technology (EMT) tire, which can be safely driven without air for at least 80 km (50 miles). The setup of the finite element model of the wheel is discussed in detail, along with a parametric study of the...

Briefs: Mechanical & Fluid Systems
Piezoelectrically Actuated Shutter for High Vacuum

A piezoelectrically actuated shutter is undergoing development for use in experiments on laser cooling of atoms. The shutter is required to be compatible with ultrahigh vacuum [pressure of...

In March of 1999, five pilots performed flight tests to evaluate the handling qualities of an F/A-18 research airplane equipped with a small-displacement center stick (ministick)...

Briefs: Mechanical & Fluid Systems
Mirrors Containing Biomimetic Shape-Control Actuators

Curved mirrors of a proposed type would comprise lightweight sheets or films containing integral, biologically inspired actuators for controlling their surface figures. These mirrors...

Deformable mirrors of a proposed type would be equipped with relatively-large-stroke microscopic piezoelectric actuators that would be used to maintain their reflective surfaces in precise...

A class of lightweight, deployable, thin-shell, curved mirrors with built-in precise-shape-control actuators is being developed for high-resolution scientific imaging. This technology incorporates a...

Planar two-dimensional arrays of thermopiles intended for use as thermal-imaging detectors are to be fabricated by a process that includes surface micromachining. These thermopile arrays...

Trending Stories

INSIDER: Robotics, Automation & Control

Human-Like Hands with Flexible, Hybrid Actuators

Articles: Test & Measurement

Mars 2020 – The Science of Mars 2020

Articles: Robotics, Automation & Control

Mars 2020 – Getting to Mars

Briefs: Electronics & Computers

Focal-Plane Arrays of Quantum-Dot Infrared Photodetectors

INSIDER: Electronics & Computers

Solid State Batteries With Ten Times More Current Density

Articles: Sensors/Data Acquisition

Mars 2020 – The Anatomy of Perseverance

Videos