Articles: Electronics & Computers
CMOS Sensors Enable Phone Cameras, HD Video
“People told me, ‘You’re an idiot to work on this,’” Eric Fossum recalls of his early experiments with what was at the time an alternate form of digital image sensor at...
NASA Spinoff: Mechanical & Fluid Systems
Rocket Technology Stops Shaking in Its Tracks
Rocket launches—or earthquakes—are already punishing experiences. But it turns out there are some things that can make them worse: like if the vibrations hit the structure...
Articles: Imaging
Orion Video Requirement Advances High-Speed, Compact Cameras
Parachute deployment is usually a fairly simple—if crucial—operation. A small pilot parachute tossed into the wind might pull free a pin securing the main...
NASA Spinoff: Sensors/Data Acquisition
Wire Sensors Alert to Dangerous Conditions in the Clouds
One common hazard facing airplanes is ice: not just on the ground, but in the air, where it can coat wings or engines. But how do you know when icing conditions exist...
Podcasts
Branimir Blagojevic, Technologist, Goddard Space Flight Center, Greenbelt, MD
During his time with former employer Science and Engineering Services, LLC, Branimir Blagojevic helped build a remote-sensing device that detected biological agents. Blagojevic currently leads the development of the Bio-Indicator Lidar Instrument (BILI), a device that...
Briefs: Electronics & Computers
Electric Field Quantitative Measurement System and Method
NASA Langley Research Center’s Electric Field Imaging (EFI) system is the only noncontact method capable of quantitatively measuring the magnitude and direction of electrostatic...
Briefs: Electronics & Computers
Auto-Balancing Series-Stacked Input DC-DC Converter
ADC-DC converter that can operate from a high input voltage is needed for future high-power space applications. However, the selection of space-qualified, high-voltage transistors and...
Briefs: Electronics & Computers
Larger-Area Integrated Electrical Metallization Dielectric Structures with Stress-Managed Unit Cells for Extreme- Environment Semiconductor Electronics Chips
The use of patterned multiple layers of thin films of metal and dielectric to form integrated circuit interconnections of transistors and/or form on-chip circuit capacitors is well known to...
Briefs: Materials
High-Temperature, Hydrophobic, Flexible Aerogel Composite and Method of Making Same
NASA’s Glenn Research Center (GRC) has developed a method for fabricating low-density, flexible aerogel composites for use as thermal insulation for myriad...
NASA’s Glenn Research Center has developed a new method for producing a shock- and corrosion-proof, superelastic, intermetallic material, NiTiNOL 60 (60NiTi),...
Briefs: Materials
Polyimide Wire Insulation Repair System
NASA’s Kennedy Space Center (KSC) seeks to license its Polyimide Wire Insulation Repair System technology to industry. The Polyimide Wire Insulation Repair System is a kit consisting of thin film...
Briefs: Materials
Lightweight, Flexible Thermal Protection System for Fire Protection
CHIEFS (Convective Heating Im provement for Emergency Fire Shelters) is being developed by NASA’s Langley Research Center to potentially improve the performance of...
Briefs: Mechanical & Fluid Systems
Airfoil-Shaped Fluid Flow Tool for Use in Making Differential Measurements
Researchers at NASA’s Marshall Space Flight Center have developed a suite of adaptable flow measurement devices that can be easily installed without compromising the structural integrity of existing conduits. With their simple installation procedures, the devices can be...
Briefs: Mechanical & Fluid Systems
Piezo-Actuated, Fast-Acting Control Valve
High-power electric propulsion systems have the potential to revolutionize space propulsion due to their extremely high performance. This can result in significant propellant savings on space vehicles, allowing the overall mass to shrink for launch on a less expensive vehicle, or to allow the space...
Briefs: Mechanical & Fluid Systems
Interface Between STAR-CCM+ and 42 for Enhanced Fuel Slosh Analysis
Fuel slosh is excited during spacecraft maneuvers. The forces and torques exerted on the spacecraft by the slosh must be controlled by the attitude control system to maintain correct pointing and spacecraft orbit. In some rare cases, the attitude control system may excite the...
Briefs: Mechanical & Fluid Systems
Mechanisms for Achieving Non-Sinusoidal Waveforms on Stirling Engines
The current state-of-the-art Stirling engines use sinusoidal piston and displacer motion to drive the thermodynamic cycle and produce power. Research performed at NASA Glenn has shown that non-sinusoidal waveforms have the potential to increase Stirling engine power density,...
Briefs: Mechanical & Fluid Systems
RFID Cavity
This technology provides a method for interrogating collections of items with radio-frequency identification (RFID) tags. It increases the read accuracy, meaning that more of the item tags will be successfully read. It also permits smaller tag antennas than would otherwise be necessary.
Briefs: Mechanical & Fluid Systems
Method for Asteroid Volatile Extraction in Space
Some meteorites representative of certain classes of asteroids are 25% or more water by weight. This is consistent with infrared spectra of some asteroids, indicating hydrated minerals are abundant in some varieties of carbonaceous chondrite asteroids. Since water is very valuable in space, it...
Briefs: Mechanical & Fluid Systems
Improving Stirling Engine Performance Through Optimized Piston and Displacer Motion
Stirling engines typically achieve high efficiency, but lack power density. Low power density prevents them from being used in many applications where internal combustion engines are viable competitors, and increases system costs in applications that require...
Briefs: Sensors/Data Acquisition
Biomarker Sensor System and Method for Multi-Color Imaging and Processing of Single-Molecule Life Signatures
NASA’s Jet Propulsion Laboratory offers a method to manufacture biomarker sensor arrays with nanoscale resolution and active regions on the order of 1 micron by applying nanolithographic direct-write techniques to the fabrication of...
Briefs: Sensors/Data Acquisition
Device and Method of Scintillating Quantum Dots for Radiation Imaging
NASA’s Langley Re search Center has developed Scintillating Quantum Dots for Imaging X-rays (SQDIX) technology that enables the creation of x-ray detectors that are more...
Briefs: Sensors/Data Acquisition
Lightning Protection and Detection System
NASA’s Langley Research Center has developed a sensor technology for structural health monitoring on composite aircraft surfaces. When conventional aircraft are struck by lightning, the result can...
Briefs: Sensors/Data Acquisition
Advanced Gas Sensors and High-Temperature Pressure Sensors
Innovators at NASA’s Glenn Research Center have developed advanced hydrogen and hydrocarbon gas sensors capable of detecting leaks, monitoring emissions, and providing in situ...
Briefs: Sensors/Data Acquisition
Minimally Intrusive Thin-Film Electrical Insulation on Conductive Surfaces
The use of thin-film sensors has several advantages over wire or foil sensors. For example, thin-film sensors do not require special machining of the components on which they are mounted, and, with thicknesses less than 10 μm, they are considerably thinner than wires or...
Briefs: Manufacturing & Prototyping
Pulsed Ultrasonic Stir Welding System
NASA’s Marshall Space Flight Center (MSFC) developed Ultrasonic Stir Welding (USW) to join large pieces of very high-strength metals such as titanium and Inconel. USW, a solid-state weld process,...
Briefs: Manufacturing & Prototyping
Method of Heat Treating Aluminum-Lithium Alloy to Improve Formability
NASA scientists have designed a novel heat treatment process that significantly improves the formability of high-performance aluminum-lithium (Al-Li) 2195 alloy plate...
Briefs: Manufacturing & Prototyping
Fuel Tank for Liquefied Natural Gas
NASA’s Marshall Space Flight Center has developed a new composite vessel technology that is suitable for use as a liquefied natural gas (LNG) fuel storage tank for alternative fuel vehicles. This...
Briefs: Manufacturing & Prototyping
Impact Tester Device
NASA’s Langley Research Center has developed a portable device to simulate low-velocity impacts on a material or structure. As composite materials are highly susceptible to damage caused by low-velocity impact, they...
Briefs: Software
Scalable and Tileable Aggregate Low-Level Summary Display for Deep Space Network Link Control Tasks
The Deep Space Network (DSN) is a collection of three sites around the globe. The positioning of the sites, 120° longitude apart, allows at least one site to see every patch of sky at all times, thus facilitating continuous coverage for any deep...
Briefs: Software
Mission Service Architecture Framework (MSAF)
The representation of mission operations systems (MOS) has been unique to each mission, although there are many common concerns that need to be addressed. A consistent approach and language are needed for representing mission operations systems. The Mission Service Architecture Framework (MSAF) is a...
Briefs: Software
Multi-Mission Operations System (MMOS)
Each mission needs to develop a Mission Operations System (MOS). Without a standard design to use as a reference, system engineers typically look to a subset of previous missions and develop a system with a mix of heritage, new design, and in some cases, reinvention of existing capabilities. If a reference...
Briefs: Software
Study of Formulating Conserved Scalar Equations for Turbulent Reactive Flows with General Species Mass- Diffusion Coefficients for Utilization in Flamelet Models
The modeling of turbulent reactive flows is a subject of contemporary research. Current turbulent-reaction models cannot account for realistic complexities such as distinct species...
Briefs: Software
HORIZON Framework for Distributed Data Management and Product Generation Workflow
The NASA Earth Observing System Data and Information System (EOSDIS) is a data-centric system designed for the processing and archiving from NASA’s Earth Observation missions and their distribution, as well as provision of specialized services to users. The major...
Briefs: Software
TIE: The Imagery Exchange for the NASA Global Imagery Browse Services (GIBS) Project
The NASA Earth Observing System Data and Information System (EOSDIS) is a data-centric system designed for processing and archiving from NASA’s Earth Observation missions and their distribution, as well as provision of specialized services to users. The major...
Briefs: Software
Space Communications and Navigation (SCaN) Game Phase III
The Space Communications and Navigation (SCaN) program is responsible for providing communications and navigation services to spaceflight missions located throughout the solar system. Astronauts, mission controllers, and scientists depend upon the reliable transmission of information...
Briefs: Software
Adverse Condition and Critical Event Prediction Toolbox (ACCEPT)
Many natural or complex engineered systems rely upon critical functions or processes that can be measured with the aid of various sensors or other novel devices. As a result, sensor and measurement data can be used to learn a parametric or non-parametric model of the behavior for a...
Briefs: Software
MATLAB Webification Science Client
The Matlab Webification Science Client consists of several functions that access remote w10n-sci repositories to retrieve data. It supports user sessions to authenticate and authorize access to restricted repositories. In command line mode, it can list the contents of a w10n-sci node, change to other nodes, and...
Briefs: Imaging
CUDA Framework for Linear Time-Invariant Control of Adaptive Optics Systems
Current science objectives, such as high-contrast imaging of exoplanets, have led to the development of high-order adaptive optics (AO) systems possessing several thousand deformable mirror (DM) actuators. These systems typically rely on integrator-based control...
Briefs: Imaging
Invertible Time Invariant Linear Filtering (InTILF) Method for Pattern Detection and Modeling of Stochastic One- or Two-Dimensional Data
X-ray astronomy offers the opportunity to observe important phenomena, including the early accretion of massive black holes and detecting diffuse ionized intergalactic gas that is heated to X-ray temperatures...
Briefs: Imaging
One-Micron (1064-nm) Planar External Cavity Laser (PLANEX)
Ahighly reliable, very low-phase, and low-amplitude-noise laser is required as an oscillator for the LISA mission. A commercial product made by Redfern Integrated Optics met these requirements (1550-nm PLANEX External Cavity Laser), but it operated at 1.5 microns, not the required LISA...
Briefs: Photonics/Optics
Stereoscopic Imaging in Hypersonic Boundary Layers Using Planar Laser-Induced Fluorescence
Stereoscopic time-resolved visualization of three-dimensional structures in a hypersonic flow was performed for the first time in NASA Langley Research Center’s 31-inch Mach 10 Air Tunnel. Nitric oxide (NO) was seeded into hypersonic boundary layer flows...
Briefs: Test & Measurement
Variably Transmittive, Electronically Controlled Eyewear
During instrument flight training, the pilot must have his/her view through the aircraft windscreen restricted to simulate low-visibility conditions while permitting the pilot to view...
Briefs: Test & Measurement
Method for Ground-to-Satellite Laser Calibration System
NASA’s Langley Research Center has developed the Ground-to-Space Laser Calibration (GSLC) system concept for calibrating Earth observing sensors measuring reflected radiance. GSLC is capable of calibrating sensitivity to polarization, degradation of optics, and response to stray light of...
Briefs: Test & Measurement
Energy Analysis Method for Hidden Damage Detection
NASA’s Langley Research Center has developed a new Non-Destructive Testing (NDT) method for identifying and characterizing hidden damage in composite materials. The new technique requires...
Briefs: Test & Measurement
Deconvolution Methods and Systems for the Mapping of Acoustic Sources from Phased Microphone Arrays
NASA’s Langley Research Center researchers developed DAMAS using an iterative algorithm to deconvolute noise signals, allowing for more...
Briefs: Test & Measurement
High-Precision Electric Gate for Time-of-Flight Ion Mass Spectrometers
NASA’s Goddard Space Flight Center has developed a high-precision electric gate (HPEG) time-of-flight (TOF) mass spectrometer to study the magnetosphere of Jupiter...
Briefs: Test & Measurement
Method of Adjusting Acoustic Impedances for Impedance-Tunable Acoustic Segments
NASA’s Langley Research Center researchers have developed an adaptive noise-reduction system that optimizes impedance in an aircraft engine. Aerospace and automotive engineers can take advantage of this innovative system that offers a superior approach to noise...
Briefs: Test & Measurement
Nanostructure Neutron Converter Layer Development
NASA’s Langley Research Center has developed a nanostructure neutron converter layer that can be used for neutron detection. Neutron radiation is a significant risk in long-duration spaceflight and is also a risk in commercial aviation and nuclear reactors. This invention provides for more...
Briefs: Test & Measurement
Mars Science Laboratory ChemCam Sun Safety
The Mars Science Laboratory (MSL) ChemCam instrument can be damaged when the Sun enters or passes through its field of view (FOV). There is no Sun cover, yet other instruments mounted with boresights pointing in the same direction must observe the Sun for scientific observations and for attitude...
Briefs: Green Design & Manufacturing
System for In-Situ Detection of Plant Exposure to Trichloroethylene (TCE)
In collaboration with the State University of New York and the Naval Research Laboratory, NASA’s Marshall Space Flight Center is developing a hyperspectral estimator...
Briefs: Green Design & Manufacturing
Time-Shifted PN Codes for CW LIDAR, RADAR, and SONAR
NASA’s Langley Research Center has developed a waveform processing technique to eliminate signal noise resulting from sources of interference (scatterers) that can degrade continuous...
Briefs: Green Design & Manufacturing
Data Informatics Infrastructure for the Megacities Carbon Project
With the goal of assessing the anthropogenic carbon-emission impact of urban centers on local and global climates, the Megacities Carbon Project has been building carbon-monitoring capabilities for the past two years around the Los Angeles metropolitan area as a pilot effort....
Briefs: Green Design & Manufacturing
Activated Metal Treatment System (AMTS) for Paints
The National Aeronautics and Space Administration (NASA) seeks partners interested in the commercial application of the Activated Metal Treatment System (AMTS) for treating polychlorinated...
Briefs: Green Design & Manufacturing
Airborne Elastic Backscatter and Raman Polychromator for Ash Detection
Volcanic ash is a significant hazard to aircraft engines and electronics. It has caused damage to unwary aircraft and disrupted air travel for thousands of travelers, costing millions of dollars. The small, jagged fragments of rocks, minerals, and volcanic glass that...
Articles: Aerospace
New Horizons for Aviation Technology
Thanks to advancements developed by NASA, today’s aviation industry is better equipped than ever to safely and efficiently transport passengers to their destinations. In fact, every U.S. aircraft and...
Articles: Aerospace
40 Years of Safer Aviation Through Reporting
The U.S. has an incredibly safe aviation system, partly because safety concerns are identified and corrected before they become real problems. NASA’s Aviation Safety Reporting System (ASRS) is...
NASA Spinoff: Sensors/Data Acquisition
Wireless Platform Integrates Sensors with Smartphones
In 2007, when the Department of Homeland Security (DHS) issued a call for a sensor that could equip a smartphone with the ability to detect dangerous gases and chemicals, Ames Research...
Articles: Software
Software Models Electromagnetics of Wireless Power Transfer
Imagine coming home and dropping your phone, laptop, and Bluetooth® headset on your kitchen table so that they all recharge simultaneously. What if you could drive your electric...
Articles: Software
Improving Weapons with Simulation
As engineers design new weapons or modify existing ones, reducing time and money on development can be critical in providing soldiers with improved weapons without undue delay. A new sight may be planned for...
Articles: Software
Simulating Material Migration
Accurately tracking and predicting the subsurface migration of specific materials over time and over multiple phases is critical to efficient and effective strategy development and deployment in a growing number...
Articles: Software
Optimizing Fuel Filters via Simulation
Cars contain numerous filters for air, fuel, and oil. Those who develop these filters are confronted with many requirements. The products must withstand intense temperature fluctuations and vibrations,...
Articles: Manufacturing & Prototyping
Designing for 3D Printing
3D printing has progressed over the past decade to include multimaterial fabrication, enabling production of powerful, functional objects. While many advances have been made, it still has been difficult for...
Articles: Photonics/Optics
Camera-Equipped Vehicles ‘See the Light’ in Cities
Imagine if every police car, bus, and garbage truck gathered important infrastructure data as they made their usual routes through the city.
In different field tests around the...
A fairly new biomedical imaging modality, optoacoustic imaging is based on the use of laser-generated ultrasound. According to the National Center for Biotechnology...
Application Briefs: Aerospace
Fabricating Optical Mirrors for Use in Outer Space Measurements
There are many ways to manufacture an optic depending on the complexity of the component and the application. From choosing the best substrate, to detailing the numerous...
Application Briefs: Aerospace
Making VR a NASA Reality
NASA researchers want to prove that a virtual reality headset like the Oculus Rift is not just a toy. Josh Kinne, a deputy project manager at NASA Langley Research Center, sees a future role for virtual and augmented...
Articles: Photonics/Optics
SPIE Photonics West 2017 Preview
The SPIE Photonics West 2017 technical conference and exhibition returns to The Moscone Center in San Francisco, January 28 through February 2, offering attendees the opportunity to explore the latest...
Products: Manufacturing & Prototyping
Product of the Month: January 2017
HP, Palo Alto, CA, unveiled the HP Z2 Mini Workstation designed for users in CAD and other compute-intensive industries. The workstation is 2.3” high, and 90% smaller than a traditional business-class...
Question of the Week: Sensors/Data Acquisition
Will the voice become a mainstream way to control our devices?
This year's Consumer Electronics Show (CES) in Las Vegas showcased many new consumer products featuring voice control. LG, for example, introduced a smart refrigerator equipped with Amazon's Alexa voice service. Other CES technologies with voice-recognition capabilities included...
INSIDER: Manufacturing & Prototyping
Researchers Design Lightweight, 'Stronger-Than-Steel' Material
A team of engineers at the Massachusetts Institute of Technology has successfully designed a new 3D material with five percent the density of steel and ten times the strength. By compressing and fusing flakes of graphene, a two-dimensional form of carbon, the sponge-link...
Question of the Week: Communications
Would you use a flexible phone?
This week's Question: The Korea Herald reported last week that Samsung is developing a "fold-in" phone. The device's flexible display folds open into a 7-inch tablet. According to the article, the team is expected to ship more than 100,000 units during the third quarter of 2017. The paper reported that the...
INSIDER: Manufacturing & Prototyping
Researchers Spin Artificial Spider Silk
Researchers from the Swedish University of Agricultural Sciences and Karolinska Institutet has, step by step, developed a way of "spinning" artificial spider silk.
INSIDER: Imaging
Light Can Switch on Topological Materials
Theoretical physicists at the Department of Energy’s SLAC National Accelerator Laboratory used computer simulations to show how special light pulses could create robust channels where electricity...
INSIDER: Photonics/Optics
New Crystal Structure Holds Promise for Optoelectronic Devices
A Florida State University research team has discovered a new crystal structure of organic-inorganic hybrid materials that could open the door to new applications for...
INSIDER: Imaging
Physics, Photosynthesis and Solar Cells
A University of California, Riverside assistant professor has combined photosynthesis and physics to make a key discovery that could help make solar cells more efficient. Nathan Gabor is focused on...
Question of the Week: Automotive
Will touchscreens take over the dashboard?
This week's Question: With backup cameras now mandatory in today's vehicles, screens in cars are increasingly becoming a standard feature. At the Consumer Electronics Show in Las Vegas this month,...
Who's Who: Sensors/Data Acquisition
Branimir Blagojevic, Technologist, Goddard Space Flight Center, Greenbelt, MD
During his time with former employer Science and Engineering Services, LLC, Branimir Blagojevic helped build a remote-sensing device that detected biological...
INSIDER Product: Photonics/Optics
Single-Frequency Lasers
LASOS (Jena, Germany) has expanded its range of single-frequency laser sources from the ultra-violet through the red. Wavelength-dependent power levels up to 300 mW are available, with spectral linewidth values less...
INSIDER Product: Imaging
Single Photon Counting Module
Excelitas Technologies® (Waltham, MA) has introduced SPCM-NIR, a Single Photon Counting Module specifically selected and performance-optimized for the near-infrared (NIR) wavelength spectrum. This...
INSIDER Product: Photonics/Optics
Time-to-Digital Converter
Mouser Electronics, Inc. , (Mansfield, TX) is now stocking the TDC7201 time-to-digital converter from Texas Instruments (TI). The TDC7201 is designed for use with ultrasonic, laser, and radar range finding...
INSIDER Product: Photonics/Optics
Laser Diode Modules
BEA Lasers (Elk Grove Village, IL) has introduced two new low-profile additions to their rugged MIL Series of laser diode modules. The new MIL RA Model features a right angle, and the new MIL Compact Model features a...
INSIDER: Semiconductors & ICs
Researchers Awaken Graphene's Hidden Superconductivity
Since its discovery in 2004, scientists have believed that graphene contained an innate ability to superconduct. Now researchers from the University of Cambridge have found a way to activate that previously dormant potential, enabling the material to carry an electrical current with zero...
Articles: Motion Control
The Basics of Encoder Selection
An application’s required positioning resolution dictates the choice of encoder resolution. A well-tuned system can maintain the position within one encoder state...
INSIDER: Motion Control
Control Scheme Improves Motor Operation and Interaction
A team of researchers from the Polytechnic University of Bari, Italy, is working to improve how industrial electric drives operate. They propose a new control scheme that will not only...
INSIDER: Medical
Tool Helps Design Soft Robots That Can Bend and Twist
Designing a soft robot to move organically — to bend like a finger or twist like a wrist — has always been a process of trial and error. Now, researchers from the Harvard John A....
Question of the Week: Materials
Will metallic hydrogen improve transportation?
This week's Question: Today's lead INSIDER story featured the development of metallic hydrogen, a technology that has a range of potential applications, from advanced rocket propellants to room-temperature superconductors. According to the Harvard University researchers, the material could support...
INSIDER: Materials
Researchers Create Metallic Hydrogen
Nearly a century after it was theorized, scientists from Harvard University have created the first-ever sample of one of the rarest materials on the planet: metallic hydrogen. The atomic metallic hydrogen has a potentially wide range of applications, including as a room-temperature superconductor.
Top Stories
Blog: Unmanned Systems

Experts Weigh In: How Will a Robotic Future Impact Nature?
INSIDER: Photonics/Optics

Orbiting Instrument Hints That Stored Magnetic Energy Heats Solar...
Podcasts: Sensors/Data Acquisition

Videos: Test & Measurement

Test System Could Enable Reduced Helicopter Vibration
Blog: Automotive

CES 2021: How COVID-19 Turned the Car into a Personal 'Second Space'
Videos: Automotive

Question of the Week
Has the Vehicle Become Your “Second Space?”
Webcasts
Upcoming Webinars: Automotive
Reducing the Cost of Quality in Automotive BiW
Upcoming Webinars: Automotive
Electric-Vehicle Transmission Development Priorities
Upcoming Webinars: Sensors/Data Acquisition
The Critical Role of Fiber Optic Temperature Sensors in Medical...
Upcoming Webinars: Manufacturing & Prototyping
Zinc Die Casting Concepts to Achieve Precision, Performance, and...
Upcoming Webinars: Test & Measurement
Radar Measurements: Triggering, Analysis, and Generation
Upcoming Webinars: Materials
Trending Stories
INSIDER: Imaging

Orbiting Instrument Hints That Stored Magnetic Energy Heats Solar Atmosphere
INSIDER: Electronics & Computers

Combining Electronic, Photonic Chips Enables Super-Fast Quantum Light Detection
Application Briefs: Robotics, Automation & Control
Motion Solutions for Electric Expansion Valves
Articles: Manufacturing & Prototyping

Special Section: The Winners of the 2020 'Create the Future' Design Contest
Briefs: Energy

Solid-State Technology Enables Smaller, Safer Batteries
Briefs: Manufacturing & Prototyping

Double-Vacuum-Bag Process for Making Resin-Matrix Composites