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Search indexed NASA NTRS and DOE OSTI research on propulsion, heat transfer, battery materials and energy systems. Follow report and document links to the original sources.
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A prototype compact reactor suitable for combustion of propane with oxygen under shallow as well as submerged deep submergence diving conditions is reported. The device is used to heat the circulating water in a water tube-type diving suit.
A water cooled garment was constructed and used to study the characteristics of independent regional cooling of the body in contrast to the current practice of uniform cooling. The cooling pads in the garment were grouped to provide independent control of water inlet temperatures and flow rates to six regions: head, upper torso, lower torso, arms, thighs, and lower legs. Experiments with and without the cooling suit were conducted with five test subjects standing and walking on a treadmill on selected schedules. Steady state and, to a lesser extent, transient characteristics were obtained.
The principles of clean room technology and the criteria for their application to surgery are discussed. The basic types of surgical clean rooms are presented along with their advantages and disadvantages. Topics discussed include: microbiology of surgery suites; principles of laminar airflow systems, and their use in surgery; and asepsis and the operating room.
The High Pressure Space Suit Glove Program yielded one prototype glove assembly with an operating pressure of 8.0 psi. The following developments are reported: (1) A new layup technique for incorporation of the mini-convolute systems; (2) modification in the mini-convolute construction to assure cycle life at 8.0 psi in excess of 100,000 cycles; (3) the development of a unique non-orthogonal low torque wrist joint; (4) the development of a low torque single axis joint for use in the thumb and finger first metacarpal joints; and (5) a number of approaches to 1st metacarpal joints were fabricated and tested to establish the joint technqiues.
An environmentally controlled suit is described consisting of an airtight outergarment attached by an airtight bellows to the wall of a sterile chamber, an undergarment providing for circulation of air near the skin of the wearer, and a circulation system comprised of air supply and distribution to the extremities of the undegarment and central collection and exhaust of air from the midsection of the undergarment. A workman wearing the undergarment and attached circulation system enters the outer garment through a tunnel in the chamber wall and the attached bellows to work in the chamber without any danger of spreading bacteria.
Surface electromyograms (EMG) taken from three upper torso muscles during a push-pull task were analyzed by a power spectral density technique to determine the utility of the spectral analysis for identifying changes in the EMG caused by muscular fatigue. The results confirmed the value of the frequency analysis for identifying fatigue producing muscular performance. Data revealed reliable differences between muscles in fatigue induced responses to various locations in the reach envelope at which the subjects were required to perform the push-pull exercise, and the differential sensitivity of individual muscles to the various reach positions; i.e., certain reach positions imposed more fatigue related shifts in EMG power than did others. It was found that a pressurized space suit changed the pattern of normal shirtsleeve muscle fatigue responses in all three of the muscles.
Theoretical and experimental work for a systems analysis approach to the problem of surgical suit exhaust systems centered on evaluation of halothane absorbing filters. An activated charcoal-alumina-charcoal combination proved to be the best filter for eliminating halothane through multilayer absorption of gas molecules.
A management systems study for future spacesuit programs was conducted to assess past suit program requirements and management systems in addition to new and modified systems in order to identify the most cost effective methods for use during future spacesuit programs. The effort and its findings concerned the development and production of all hardware ranging from crew protective gear to total launch vehicles.
A lightweight and inexpensive coverlayer developed for space suits is described. Material selection, procurement, and testing, pattern design, and prototype fabrication are discussed. By using the minimum required cross section necessary for earth orbital mission, by utilizing the lightest weight materials possible, and by decreasing the use of weight costly taping a lightweight and economical thermal micrometeroid garment was developed. Simplification of manufacturing techniques and use of off-the-shelf materials helped to reduce costs.
A pair of pressure and thermal insulating overgloves to be used with an Extravehicular (EV) suit assembly was designed, developed, fabricated, and tested. The design features extensive use of Nomex felt materials in lieu of the multiple layer insulation formerly used with the Apollo thermal glove. The glove theoretically satisfies all of the thermal requirements. The presence of the thermal glove does not degrade pressure glove tactility by more than the acceptable 10% value. On the other hand, the thermal glove generally degrades pressure glove mobility by more than the acceptable 10% value, primarily in the area of the fingers. Life cycling tests were completed with minimal problems. The thermal glove/pressure glove ensemble was also tested for comfort; the test subjects found no problems with the thermal glove although they did report difficulties with pressure points on the pressure glove which were independent of the thermal glove.
A series of materials for use as an improved restraint layer in the shuttle space suit was developed. The feasibility of weaving triaxial fabrics in tight, low porosity configurations with yarns of appropriate sizes and materials was demonstrated along with the stability and isotropy of triaxial fabrics. The triaxial fabric constructions, BP44P and BP40M, can be reproduced on a production basis. Both fabric constructions afford excellent strength-to-weight ratio and exhibit improved tear strength and shear resistance over biaxial fabrics.
Canopy reflectance calculations for a spring type Mexican wheat, Penjamo, are compared with published data on Scout winter wheat. Good agreement exists between model calculations and experimental data in the spectral range, 500 nm to 750 nm, suggesting that the model parameters for wheat can be applied to different cultivars of wheat in the same growth stage. Wheat canopy reflectance is dependent upon surface soil type and this dependency is examined with the Suits' spectral model. In this particular growth stage wheat reflectance is shown to be nearly independent of soil reflectance in the visible wavelengths and progressively dependent at longer wavelengths in the infrared.
A frusto-conically shaped distensible component is described which inflates to encircle a portion of the wearer's head and carries a collapsible member which automatically extends over the remaining portion of the head. A pulley arrangement secured between the walls of the distensible component automatically extends and retracts the collapsible member. When deflated, the unit is carried on the back of the wearer so as to provide an automatic emergency space suit helmet.
Size can be used as a criterion to select 18 large (larger than 1 cm) samples from among 148 melt-rock fragments of all sizes. This selection provides a suite of large samples which represent the important chemical variants among highland melt rocks; each large sample has enough material for a number of sample-destructive studies, as well as for future reference. Cluster analysis of the total data base of 148 highland melt rocks shows six distinct groups: anorthosite, gabbroic anorthosite, anorthositic gabbro ('highland basalt'), low K Fra Mauro, intermediate-K Fra Mauro, and high-K. Large samples are available for four of the melt-rock groups (gabbroic anorthosite, anorthositic gabbro, low-K Fra Mauro, and intermediate-K Fra Mauro). This sample selection reveals two subgroups of anorthositic gabbro (one anorthite-poor with negative Eu anomaly and one anorthite-rich without Eu anomaly). There is a sharp distinction between those Apollo 16 melt rocks and glasses which have both been classified as 'gabbroic anorthosite'.
A study of the petrology of the Apollo 12 pigeonite basalt samples 12011, 12043, and 12007 is presented. In this suite, the abundances of olivine and Cr-spinel decrease with increasing grain size, while the abundances of plagioclase and ilmenite increase. The petrochemical and textural variations indicate that the pigeonite basalts were derived from the olivine basalts, but the compositional gap between the olivine and pigeonite basalts indicates that they could not have crystallized together from a single, initially homogeneous magma body.
An alternative space suit insulation concept using a monolayer woven pile material is discussed. The material reduces cost and improves the durability of the overgarment, while providing protection similar to that provided by multilayer insulation (MLI). Twelve samples of different configurations were fabricated and tested for compressibility and thermal conductivity as a function of compression loading. Two samples which showed good results in the initial tests were further tested for thermal conductivity with respect to ambient pressure and temperature. Results of these tests were similar to results of the MLI tests, indicating the potential of the monolayer fabric to replace the present MLI. A seaming study illustrated that the fabric can be sewn in a structurally sound seam with minimal heat loss. It is recommended that a prototype thermal meteroid garment be fabricated.
A measurement system for simultaneously measuring torque and angular flexure in a pressure suit joint is described. One end of a joint under test is held rigid. A torque transducer is pivotably supported on the other movable end of a joint. A potentiometer is attached to the transducer by an arm. The wiper shaft of the potentiometer is gripped by a reference arm that rotates the wiper shaft the same angle as the flexure of joint. A signal is generated by the potentiometer which is representative of the joint flexure. A compensation circuit converts the output of the transducer to a signal representative of joint torque.
A low-drag truck consisting of a tractor-trailer rig characterized by a rounded forebody and a protective fairing for the gap conventionally found to exist between the tractor and the trailer is described. The fairing particularly suited for establishing an attached flow of ambient air along its surfaces. The truck is also comprised of a forward facing, ram air inlet and duct and a plurality of submerged inlets and outflow ports communicating with the trailer for continuously flushing heated gases from the trailer as the rig is propelled at highway speeds.