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Tension Stiffened and Tendon Actuated Manipulator

This configuration offers mechanical advantage and improved efficiency over existing arms that use weighty gearboxes and motors. Langley Research Center, Hampton, Virginia NASA’s Langley Research Center is developing a robotic arm with lightweight joints that provide a wide range of motion. The envisioned design provides users with a long reach and numerous degrees of freedom. The arm, ideal for use in aquatic environments or for manipulation of light terrestrial loads, consists of articulating booms connected by antagonistic cable tension elements. The arm elements are structurally efficient and lightweight, and support compact packaging. The inherent mechanical advantage provided by the tendon articulation allows the use of small, efficient motor systems. The manipulator can be scaled over a large range from 10 m (load-bearing arm) to over 1000 m (submersible or float-supported arm). Current efforts are focusing on a 15-m prototype and a 300-m subsystem to test the unique robotic architecture. NASA is seeking partners to assist with the development of its concept system for specific applications.

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Lattice Structures Coating Concept for Efficient Thermal Linking Beds

Marshall Space Flight Center, Alabama Conventional air revitalization technology for removal of CO2, moisture, and trace organic contaminants usually involves a packed bed of sorbent pellets that can be regenerated using a concept similar to that of pressure swing adsorption (PSA). Additional heat input for thermal regeneration is preferred during the adsorption-desorption process to increase the regeneration efficiency. Typically, a pair of adsorber modules consisting of the same sorbent material with identical loading capacity is placed in parallel and work in tandem, where one module adsorbs the contaminants from the process air while the other is in regeneration mode. The two adsorber modules have separate housings and may be placed in separate locations.

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A Statistically Based Approach to Broadband Liner Design and Assessment

The current method targets the entire broadband frequency spectrum simultaneously. Langley Research Center, Hampton, Virginia The broadband component of fan noise has grown in relevance with the utilization of increased bypass ratio and advanced fan designs. Thus, while the attenuation of fan tones remains paramount, the ability to simultaneously reduce broadband fan noise levels has become more attractive. Advanced manufacturing techniques have also opened new possibilities for the implementation of broadband liner concepts. This innovation is an integrated method for the design and evaluation of novel broadband acoustic liner concepts for complex engine configurations.

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Connection and Repair Techniques for Capillary Tubing in Restrictive Areas and Gas Chromatography Applications

John F. Kennedy Space Center, Florida Capillary columns offer challenges in gas chromatography (GC) work due to their small size and fragile nature. Typical repair techniques to join two capillary columns require cumbersome metal fittings. This solution is not applicable in all situations due to size and mass limitations. Another repair or joint technique involves the use of polyimide glue with a tapered glass union. Without the bulky glass fitting, this technique is difficult to perform without plugging the column; the low-viscosity glue wicks up the capillary column and fills the small opening of the joint. Polyimide is also a problem due to its hydrolysis when trying to analyze water; the polyimide glue interacts with the water in the sample and affects the analysis. These solutions don’t support a repair of capillary columns for water analysis in a small gas chromatograph module.

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Method to Improve the Synthesis Process of High-Purity Bulk Multi-Element Compounds

Marshall Space Flight Center, Alabama Multi-element compounds have been used ubiquitously in various applications, including electronics, optics, opto-electronics, thermoelectrics, superconductivity, and the recently developed application of spintronics. Besides being the main components of some of these devices, the bulk form of these compounds is needed as a standard for fundamental property characterizations as well as the starting materials for thin-film deposition. Hence, the chemical purity and crystalline quality of these bulk compounds are critical for the applications.

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Laser Subdivision of the Genesis Concentrator Target Sample 60000

Lyndon B. Johnson Space Center, Houston, Texas A need arose for approximately 1 cm2 of a diamond-like-carbon (DLC) concentrator target for the analysis of solar wind nitrogen isotopes. The original target was a circular quadrant with a radius of 3.1 cm; however, the piece did not survive intact when the spacecraft suffered an anomalous landing upon returning to Earth. An estimated 75% of the DLC target was recovered in at least 18 fragments. The largest fragment, Genesis sample 60000, was designated for this allocation, and is the first sample to be subdivided using a laser scribing system. Laser subdivision has associated risks, including thermal diffusion of the implant if heating occurs, and unintended breakage during cleavage. In order to minimize the possibility of unintended breakage of the actual target wafer during subdivision, a careful detailed study involving numerous laser scribing plans was undertaken. The innovation described here involves the results of this study that yielded a cutting plan essentially guaranteeing ~100% cleaving success of this precious space-exposed wafer.

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Fabrication of an Integrated Photonic Waveguide Joint in Micromachined Silicon

This technology could be used in any MEMS or micromachined structure that requires multiple levels of topography. Goddard Space Flight Center, Greenbelt, Maryland High-aspect-ratio silicon structures are necessary components in many MEMS (microelectromechanical systems). Aspect ratio is defined as the ratio of the height of the structure to its lateral width. The structures are typically fabricated through bulk micromachining steps such as deep reactive ion etching. In some cases, multiple levels of high-aspect-ratio structures are required. For instance, one may want to etch completely through a silicon wafer to thermally isolate a bolometer or provide waveguide coupling to an antenna defined on an insulating membrane, and at the same time have integrated high-topology structures required for microwave coupling or filtering. Definition of the structures typically uses photolithographic technology. But for high-aspect-ratio structures, spin cast resist becomes difficult to incorporate due to the non-uniform thickness of the resist around tall structures. One can cast very thick layers of photoresist, but this limits the minimum feature size, and additionally, very thick layers of photoresist are difficult to work with due to solvent release and moisture that can cause the resist to crack or swell. For electromagnetic reasons, the structures would preferably be made from conductive material such as metal or degeneratively doped silicon. The objective of this work was to incorporate multiple levels of conductive high-aspectratio structures with standard micromachining processes.

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