Manufacturing & Prototyping

Non-Pyrotechnic Zero-Leak Normally Closed Valve

This valve is designed to create a zero-leak seal in a liquid propulsion system that is a functional replacement for the normally closed pyrovalve. Unlike pyrovalves, Nitinol is actuated by simply heating the material to a certain temperature, called the transition temperature. Like a pyrovalve, before actuation, the upstream and downstream sections are separated from one another and from the external environment by closed welded seals. Also like pyrovalves, after actuation, the propellant or pressurant gas can flow without a significant pressure drop but are still separated from the external environment by a closed welded seal.

Posted in: Briefs, TSP, Manufacturing & Prototyping, Sensors and actuators, Sensors and actuators, Valves, Liquid propellant rocket engines

Quick-Change Ceramic Flame Holder for High-Output Torches

In addition to jet engine simulation, this technology can be used in torches for forging and pottery kilns.

Researchers at NASA’s Langley Research Center have developed a new ceramic design flame holder with a service temperature of 4,000 °F (2,204 °C). The combination of high strength and high temperature capability, as well as a twist-lock mounting method to the steel burner, sets this flame holder apart from existing technology.

Posted in: Briefs, Manufacturing & Prototyping, Ceramics, Heat resistant materials, Fittings, Mountings, Nozzles

Processing Nanostructured Sensors Using Microfabrication Techniques

Nanostructured sensors have uses in safety, environmental monitoring, fire detection, and security.

Standard microfabrication techniques can be implemented and scaled to help assemble nanoscale microsensors. Currently nanostructures are often deposited onto materials primarily by adding them to a solution, then applying the solution in a thin film. This results in random placement of the nanostructures with no controlled order, and no way to accurately reproduce the placement. This method changes the means by which microsensors with nanostructures are fabricated. The fundamental advantage to this approach is that it enables standard microfabrication techniques to be applied in the repeated manufacture of nanostructured sensors on a microplatform.

Posted in: Briefs, TSP, Manufacturing & Prototyping, Sensors and actuators, Sensors and actuators, Fabrication, Nanotechnology

Modular Habitats Comprising Rigid and Inflatable Modules

Potential applications include hurricane-relief housing.

Modular, lightweight, fully equipped buildings comprising hybrids of rigid and inflatable structures can be assembled on Earth and then transported to and deployed on the Moon for use as habitats. Modified versions of these buildings could also prove useful on Earth as shelters that can be rapidly and easily erected in emergency situations and/or extreme environments: examples include shelters for hurricane relief and for Antarctic exploration.

Posted in: Briefs, TSP, Manufacturing & Prototyping, Life support systems, Composite materials, Fabrics, Materials properties

More About N₂O-Based Propulsion and Breathable-Gas Systems

A concept was evaluated of using nitrous oxide as (1) a monopropellant in thrusters for space suits and spacecraft and (2) a source of breathable gas inside space suits and spacecraft, both by exploiting the controlled decomposition of N2O into N2 and O2. Relative to one prior monopropellant hydrazine, N2O is much less toxic, yet offers comparable performance. N2O can be stored safely as a liquid at room temperature and unlike another prior monopropellant hydrogen peroxide does not decompose spontaneously. A prototype N2O-based thruster has been demonstrated. It has also been proposed to harness N2O-based thrusters for generating electric power and to use the N2 + O2 decomposition product as a breathable gas. Because of the high performance, safety, and ease of handling of N2O, it can be expected to be economically attractive to equip future spacecraft and space suits with N2O-based thrusters and breathable-gas systems.

Posted in: Briefs, Manufacturing & Prototyping, Liquid propellants, Spacecraft fuel, Gases, Materials properties, Spacesuits

Practical Loop-Shaping Design of Feedback Control Systems

Actuator rates are incorporated into a design from the start.

An improved methodology for designing feedback control systems has been developed based on systematically shaping the loop gain of the system to meet performance requirements such as stability margins, disturbance attenuation, and transient response, while taking into account the actuation system limitations such as actuation rates and range. Loop-shaping for controls design is not new, but past techniques do not directly address how to systematically design the controller to maximize its performance. As a result, classical feedback control systems are designed predominantly using ad hoc control design approaches such as proportional integral derivative (PID), normally satisfied when a workable solution is achieved, without a good understanding of how to maximize the effectiveness of the control design in terms of competing performance requirements, in relation to the limitations of the plant design.

Posted in: Briefs, TSP, Manufacturing & Prototyping, Architecture, Electronic control systems, Sensors and actuators, Architecture, Electronic control systems, Sensors and actuators

Fully Printed High-Frequency Phased-Array Antenna on Flexible Substrate

This flexible design enables applications in high-frequency RFID sensors, smart cards, electronic paper, and flat-screen displays.

To address the issues of flexible electronics needed for surface-to-surface, surface-to-orbit, and back-to-Earth communications necessary for manned exploration of the Moon, Mars, and beyond, a room-temperature printing process has been developed to create active, phased-array antennas (PAAs) on a flexible Kapton substrate.

Posted in: Briefs, TSP, Manufacturing & Prototyping, Antennas, Integrated circuits, Wireless communication systems, Antennas, Integrated circuits, Wireless communication systems, Additive manufacturing, Spacecraft

Turbomolecular Pumps for Holding Gases in Open Containers

Thermal gas atoms would be trapped; much faster atoms would pass through.

Proposed special-purpose turbomolecular pumps denoted turbotraps would be designed, along with mating open containers, to prevent the escape of relatively slowly (thermal) moving gas molecules from the containers while allowing atoms moving at much greater speeds to pass through. In the original intended applications, the containers would be electron-attachment cells, and the contained gases would be vapors of alkali metal atoms moving at thermal speeds that would be of the order of a fraction of 300 meters per second. These cells would be parts of apparatuses used to measure fluxes of neutral atoms incident at kinetic energies in the approximate range of 10 eV to 10 keV (corresponding to typical speeds of the order of 40,000 m/s and higher). The incident energetic neutral atoms would pass through the cells, wherein charge-exchange reactions with the alkali metal atoms would convert the neutral atoms to negative ions, which, in turn, could then be analyzed by use of conventional charged-particle optics.

Posted in: Briefs, TSP, Manufacturing & Prototyping, Containers, Gases, Pumps

Serrating Nozzle Surfaces for Complete Transfer of Droplets

A method of ensuring the complete transfer of liquid droplets from nozzles in microfluidic devices to nearby surfaces involves relatively simple geometric modification of the nozzle surfaces. The method is especially applicable to nozzles in print heads and similar devices required to dispense liquid droplets having precise volumes. Examples of such devices include heads for soft printing of ink on paper and heads for depositing droplets of deoxyribonucleic acid (DNA) or protein solutions on glass plates to form microarrays of spots for analysis.

Posted in: Briefs, Manufacturing & Prototyping, Machining processes, Nozzles

Triaxial Swirl Injector Element for Liquid-Fueled Engines

The design is amenable to low-cost production.

A triaxial injector is a single bi-propellant injection element located at the center of the injector body. The injector element consists of three nested, hydraulic swirl injectors. A small portion of the total fuel is injected through the central hydraulic injector, all of the oxidizer is injected through the middle concentric hydraulic swirl injector, and the balance of the fuel is injected through an outer concentric injection system. The configuration has been shown to provide good flame stabilization and the desired fuel-rich wall boundary condition.

Posted in: Briefs, Manufacturing & Prototyping, Liquid propellants, Nozzles, Fuel injection, Hydraulic equipment

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