Special Coverage

Lightweight Internal Device to Measure Tension in Hollow- Braided Cordage
System, Apparatus, and Method for Pedal Control
Dust Tolerant Connectors
Foldable and Deployable Power Collection System
Iodine-Compatible Hall Effect Thruster
Development of a Novel Electrospinning System with Automated Positioning and Control Software
Home

System for Observing Dynamic Atmospheric Phenomena

System has drastically increased transmitter capability at much reduced cost. NASA’s Jet Propulsion Laboratory, Pasadena, California Existing observing systems are inadequate to measure a variety of dynamic atmospheric processes. Ground-based or airborne systems do not observe over sufficiently large regions to capture the context or time history of many phenomena. Space-based systems do not observe a specific region over sufficient duration with sufficient spatial resolution to capture the essential features of the phenomena. Radar systems are limited in what they can observe because of the need for scattering sources to be present in the observed volume.

Posted in: Briefs, Physical Sciences

Read More >>

Covariance Analysis of Astrometric Alignment Estimation Architectures for Precision Dual-Spacecraft Formation Flying

A paper highlights analysis of proposed navigation systems and architectures for achieving precise dual-spacecraft astrometric alignment. The dynamics of dual-spacecraft relative motion, within a restricted n-body problem framework, are shown to reduce to a simple linear form for use in estimation filter design and error analysis for a deep space mission application, such as MASSIM (Milli-Arc-Second Structure Imager). This model is augmented with simplified measurement process models of relevant measurement types. These include inertial sensors, such as accelerometers and rate gyros, as well as optical alignment sensors, such as star and laser beacon trackers. A consider-state covariance analysis tool is developed from these process models and used to study the performance of proposed estimation architectures for the MASSIM application. This work develops a generic analysis methodology for evaluation of dual-spacecraft relative navigation systems and architectures for precise dual-spacecraft astrometric alignment.

Posted in: Briefs, TSP, Physical Sciences

Read More >>

Automated Purgatoid Identification

An algorithm was developed that automatically processes images captured by the HiRISE camera on the Mars Reconnaissance Orbiter to identify and locate the presence of purgatoids in monochrome images.

Posted in: Briefs, TSP, Physical Sciences

Read More >>

Interplanetary CubeSats

A report describes upgraded CubeSat satellite elements for the interplanetary environment, with solar sail propulsion and the interplanetary superhighway for navigation and maneuvering. They can host small, capable instruments and optical telecommunications on a mission to map the composition of a sequence of near-Earth asteroids and planetary bodies.

Posted in: Briefs, TSP, Physical Sciences

Read More >>

Spacecraft Line-of- Sight Stabilization Using LWIR Earth Signature

Applications could include remote science and planetary science missions, Earth surveillance and reconnaissance, and deep space optical communication. Until the time of this reporting, when a space vehicle required a reference signal for inertial pointing, the choices were a signal beacon from an Earth location, the Earth radiance in the visible spectrum, or a star tracker. However, limitations can arise from using these techniques. For example, the signal beacon suffers from limited signal power (either in RF or optical) and will constrain the application to limited ranges, errors due to stray-light and centroiding limit the accuracy of a star tracker, and the spatial/temporal variability of the Earth’s albedo and its illumination by the Sun introduces limitations when used in the visible or near infrared light.

Posted in: Briefs, Physical Sciences

Read More >>

Transportable Instrumentation Package for In-Vehicle On-Road Data Acquisition

This portable data acquisition system is a viable alternative to first developing a fully instrumented test vehicle. The study of driver behavior can provide a wealth of information that can be useful in the design of automobiles including active safety features and functions. There may be differences in driver behavior, as reflected in driver state, and these differences may be confounded by a driver’s condition. Much can be learned from studies that look at driver state and condition to answer questions such as how vehicle features and functionality could be designed to complement the driver’s capabilities and limitations in the vehicle. Also, a better understanding could be gained to determine how, or if at all, a safety feature’s characteristics should be modified to accommodate a driver’s condition.

Posted in: Briefs, Physical Sciences, Data Acquisition

Read More >>

Variable Camber Aerodynamic Control Surfaces and Active Wing Shaping Control

Concepts are examined to reduce aerodynamic drag and decrease fuel consumption. A new concept of aircraft aerodynamic control surfaces has been developed in connection with another new concept of active wing shaping control for reducing aircraft drag that will result in less fuel burn. The first concept is referred to as a variable camber continuous trailing edge flap or, alternatively, a variable camber continuous leading edge slat. The variable camber trailing edge flap (or leading edge slat) comprises multiple chord-wise segments (three or more) to form a cambered flap surface, and multiple span-wise segments to form a continuous trailing edge (or leading edge) curve with no gaps that could be prescribed by a mathematical function or the equivalent with boundary conditions enforced at the end points to minimize tip vorticities. Aerodynamic simulations have shown that this type of flap can reduce aerodynamic drag substantially as compared to a conventional flap. A new active wing-shaping control concept is proposed in connection with the presently disclosed variable camber continuous trailing edge flap (or leading edge slat). The active wing-shaping control is designed to change a wing shape in-flight in order to achieve a desired optimal wing shape for optimal drag reduction.

Posted in: Briefs, Physical Sciences

Read More >>

The U.S. Government does not endorse any commercial product, process, or activity identified on this web site.