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Permanent magnets for footwear restraint and mobility in zero gravity spacecraft, testing neutral buoyancy and six degree of freedom simulation effects
Primate restraint harness of nylon jacket and cotton cot on aluminum frame padded seat for bone resorption and calcium metabolism studies
Peak resonant response of thin rectangular plate with elastic edge restraint under concentrated load
Shoulder-harness and lap-belt restraint system was designed to be worn by individuals of widely different sizes and to permit normal body motion except under sudden deceleration. System is divided into two basic assemblies, lap belt and torso or shoulder harness. Inertia-activated reels immediately lock when seat experiences sudden deceleration.
The technical requirements and restraints imposed by the ERTS spacecraft upon the Delta launch vehicle, shroud system, associated launch complex, and range are presented for technical coordination among various agencies involved in the launch vehicle and launch operations. The payload and spacecraft systems are described, and the mission, design, test, and launch base data are outlined.
The effect of altered weight upon animal tolerance to restraint was determined by simulating various accelerative forces with directed lead weights using restrained and nonrestrained domestic fowl (chickens). Weighting (increased weight) and conterweighting (reduced weight) produced a stressed condition - reduced relative lymphocyte counts, loss of body mass, and/or the development of a disorientation syndrome - in both restrained and nonrestrained (caged only) birds. The animal's tolerance to altered weight appeared to be a function of its body weight. Unrestrained birds were stressed by counterweighting (mean plus or minus standard error) 58.3 plus or minus 41% of their body weight, whereas restrained birds tolerated only 32.2 plus or minus 2.6% reduction in body weight. A training regimen for restrained birds was not effective in improving their tolerance to a reduced weight environment. It was concluded that domestic fowl living in a weightless (space) environment should be restrained minimally and supported by ventrally directed tension equivalent to approximately 50% of their body mass (their weight in a 1 G environment).
The legal restraints on the use of electronic communications systems for dissemination of instructional materials in the United States are discussed. First the laws are examined relating to public school elementary and secondary education, with primary emphasis on selection of courses of study and instructional materials. The second part contains an examination of the copyright laws, both the copyright law now in effect and the revision thereto currently pending before the Congress of the United States.
A restraint system for securing a person to an ergometer while exercising under zero gravity conditions or while operating the ergometer in earth environment in a position other than the upright position. A padded, form-fitting body belt fits around the operator's waist and suspenders are attached to the body belt. The body belt is secured to the ergometer forwardly and rearwardly of the ergometer seat by adjustable belts joined to the body belt and releasably hooked to the ergometer frame.
Photon absorptiometry was used to evaluate bone mineral kinetics associated with normal development and the possible perturbations to bone development resulting from hypergravity exposure over a period of six months in developing Beagles. A series of seven measurements were performed at specific times with the first measurement prior to treatment and subsequent measurements at 2, 5, 9, 14, 20 and 26 weeks from the onset of the experiment. Four groups of six male Beagle pups, ranging in age from 85 to 92 days were studied. Two groups were chronically exposed to hypergravity treatments by centrifugation of 2.0 G (18.0 RPM, 11.7 ft radius) and 2.6 G (18.0 RPM, 19.8 ft radius) for the 26 week period. A third group of six dogs served as a caged control to evaluate possible changes due to confinement in small plexiglass cages similar to those of the centrifuge. Thus this control group was subjected to limited exercise due to caging restraint. The fourth group of animals was housed in open runs to allow exercise without the spatial confinement of the smaller plexiglass cages. Results show highly significant differences in body weight, bone length, increase in bone density of control group relative to other groups, and a decrease in bone mineral content in the two gravity treated groups.
The purpose of this document is to provide a single source of information regarding Agena D mission capabilities and restraints which affect spacecraft design. Utilized as a handbook during conceptual design and program planning, this catalog is intended to supplement the designer's knowledge of the Agena D and specify guidelines that enable him to design a spacecraft configuration which is: - Compatible with the booster system - Designed to realize maximum capabilities of the existing launch vehicle and associated equipment
A study was conducted to evaluate and select a suitable restraint material for the exterior of space suits pressurized to 4.0 PSID for normal operations, and to develop and improve tucked fabric joints for motions associated with the human shoulder, elbow, knee, waist, hip, ankle, and wrist. The many attributes of the end items are summarized to include structural integrity, simplicity, low maintenance, lightweight, high durability, low elongation, full range mobility, long life, and resistance to degradation in the operational environment.
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.
Subjects monitored a visual display for occasional increments in the horizontal movement of a bar of light. When the display was viewed without head restraint, detection probability was directly related to the amplitude of the increments in movement which constituted critical signals and inversely related to background event rate (the frequency of neutral events in which critical signals were embedded). When positioning of the head was restrained by a headrest, the detectability of low-amplitude signals was enhanced considerably and the influence of background event rate was attenuated. The results are considered as providing further support for the importance of sense mode coupling in visual monitoring.
The protective effects of certain polypeptides on gastric ulcerations caused from reserpine and phenylbutazone in the rate were studied. It was found that the Kunitz enzymatic inhibitor exerts a protective action in regard to gastric lesions. However, the inhibitor did not change the development of Shay ulcers and stress ulcers from restraint.
A study of the influence of ambient temperature on the production of restraint ulcers in the rat is described. It concludes that the production of restrain ulcers, is favored by the reduction of the environmental temperature, whether the rat has been subjected to a fast or not.
An experiment is described which was designed to cause ulcers in rats, but requiring less restraint time than previously used procedures. The method and results are presented.
The role of sensory simulation in restrained rats was investigated. Both mixed audio-visual and pure sound stimuli, ineffective in themselves, were found to cause a significant increase in the incidence of restraint ulcers in the Wistar Rat.
The Manned Maneuvering Unit (MMU), a self-contained zero-gravity backpack designed for astronaut extravehicular activity, is discussed with reference to the system requirements and characteristics, and potential near-term and future uses. Attention is given to the MMU man-machine interfaces, propulsion capability, attitude control, crew restraint hardware, donning, doffing, activation, and deactivation. Specific applications discussed include: spacecraft inspection and servicing, assembly of large space systems, payload deployment/retrieval, and crew rescue.