Home

Multiphysics Piezoelectric Finite Element Modeling for Designing a Piezoelectric Damping Treatment for Vibration Control of Rotating Blades

This modeling approach can be used in designing lighter, more compact, and more efficient actuators and control systems. John H. Glenn Research Center, Cleveland, Ohio The requirements for advanced aircraft engine components lead to designs that are more lightweight and efficient, yet more susceptible to excessive vibration, complex dynamic behavior, and uncertain durability and reliability. This complex nature of the dynamic behavior also leads to thicker blade designs; hence, increased fuel burn, increased noise, potentially reduced engine life, and increased maintenance costs. As part of the NASA Aeronautics Research Fixed Wing (FW) Project, Glenn Research Center has been investigating potential technologies that support the FW goals for lighter, quieter, and more efficient aircraft.

Posted in: Briefs, Electronics & Computers

Read More >>

Decelerator System Simulation (DSS)

Lyndon B. Johnson Space Center, Houston, Texas The Crew Exploration Vehicle Parachute Assembly System (CPAS) project conducts computer simulations to verify that requirements on flight performance, parachute loads, and terminal rate of descent are met. The objective of this work was to obtain a high-fidelity simulation of Orion crew capsule flight test vehicles during parachute flight.

Posted in: Briefs, TSP

Read More >>

EXOS Software

Lyndon B. Johnson Space Center, Houston, Texas An improved version of EXOS software allows for the modeling of fabrics, mixtures, and porous materials, and also provides the ability to accept hex mesh geometries. The code employs a novel numerical method, a hybrid particle finite element approach, as well as particles and elements in tandem, each modeling distinct aspects of the physics. Ellipsoidal particles are used to model contact-impact and volumetric thermomechanical response (Euler parameters provide a singularity-free description of particle rotations). Elements are used to model “strength” effects; namely, tensile inter-particle forces and elastic-plastic deviatoric deformation.

Posted in: Briefs, TSP, Electronics & Computers, Coatings & Adhesives

Read More >>

Wireless Multi-Walled Carbon Nanotube Microwave Heater System Using RFID-Based Temperature Feedback

This heater can be used in condensation control in inflatable structures, or in aircraft de-icing. Lyndon B. Johnson Space Center, Houston, Texas This innovation has two main parts — a wireless, flexible film heater containing multi-walled carbon nanotubes (MWCNTs) to convert radiated microwave energy into heat, and a radio frequency identification (RFID) temperature sensor to provide wireless temperature feedback.

Posted in: Briefs, TSP, Sensors

Read More >>

Sub-Audible Speech Recognition Based on Electromyographic (EMG) Signals

This technology can be used by medical and emergency service workers, persons with disabilities, and in homeland security, underwater operations, and robotic control. Ames Research Center, Moffett Field, California Sub-audible speech is a new form of human communication that uses tiny neural impulses (EMG signals) in the human vocal tract instead of audible sounds. These EMG signals arise from commands sent by the brain’s speech center to tongue and larynx muscles that enable production of audible sounds. Sub-audible speech arises from EMG signals intercepted before an audible sound is produced and, in many instances, allows inference of the corresponding word or sound. Where sub-audible speech is received and appropriately processed, production of recognizable sounds is no longer important. Further, the presence of noise and of intelligibility barriers, such as accents associated with the audible speech, no longer hinder communication.

Posted in: Briefs, Sensors

Read More >>

Precision Detector Conductance Definition via Ballistic Thermal Transport

This innovation could be applied in the development of bolometric detector array sensors. Goddard Space Flight Center, Greenbelt, Maryland The characteristics of a thermal detector, such as sensitivity, response time, and saturation power (or energy resolution), are functions of the thermal conductance of the detector to its cryogenic environment. The thermal conductance is specified to achieve a tradeoff among the highest sensitivity, allowed response time, and the desired saturation energy or power budget for the particular application. It is essential to achieve the design thermal conductance (within an acceptable variance) after a thermal detector has been fabricated. Otherwise, the detector will fail to achieve its desired functionality. In addition, the formation of a multi-pixel imaging array becomes difficult and costly when the design thermal conductance is not achieved with high post-fabrication yield.

Posted in: Briefs, TSP, Sensors

Read More >>

Improved Ground Collision Avoidance System for General Aviation Aircraft and UAVs

This advanced warning system uses cutting-edge fighter jet technology to prevent controlled flight into terrain, which is a leading cause of aviation fatalities. Armstrong Flight Research Center, Edwards, California Controlled flight into terrain (CFIT) causes almost 100 deaths each year in the United States. Although warning systems have virtually eliminated CFIT for large commercial air carriers, the problem still remains for general aviation aircraft and unmanned aerial vehicles (UAVs). Existing systems are forced to rely on digital maps with low resolution/fidelity. They also require expensive equipment, limit the maneuvers to avoid collision, and frequently issue false alarms, causing pilots to ignore the safety system.

Posted in: Briefs, Sensors

Read More >>