43,792 research outputs found
Fabric for micrometeoroid protection garment Patent
Structure of fabric layers for micrometeoroid protection garment with capability for eliminating heat shorts for use in manufacturing space suit
Polarimeter provides transient response in nanosecond range
Conventional polarimeter with a Senarmont compensator improves transient response and eliminates manual manipulation. A sampled photomultiplier output is fed to a low pass filter, resulting in a signal representing the optical state existing at the instant of sampling. With this technique, an unknown transient-induced retardation can be measured
Multiple environment materials test chamber having a multiple port X-ray tube for irradiating a plurality of samples Patent
Multisample test chamber for exposing materials to X rays, temperature change, and gaseous conditions and determination of material effect
Focal plane array optical proximity sensor
An optical proximity sensor for optically detecting an object within a predetermined detection volume is described. More specifically, an optical proximity sensor is disclosed having an illuminator assembly including lens and a plurality of light-emitting diodes located at first predetermined positions along the focal plane of the illuminator lens. A detector assembly including a detector lens and a plurality of photodiodes located at second predetermined positions along the focal plane of the detector lens is also provided. The two lenses are spaced apart a predetermined distance in order to define a predetermined detection volume. Additionally, a combination of optical proximity sensors, according to the invention, is disclosed wherein the sensors can be used in conjunction with a vehicle to provide a safety system for warning an operator when an object is within a volume defined by the proximity sensor combination
Polarimeter for transient measurement Patent
Automatic polarimeter capable of measuring transient birefringence changes in electro-optic material
Multiple test chamber exposes materials to various environments
Multiple compartment test chamber exposes several material specimens to various environmental conditions for prolonged periods. The specimens are individually mounted in chamber compartments, rotated to various positions, and measured through optical windows to determine progressive changes in the material properties
Improved heat-resistant garments
Fabrication method for protective clothing eliminates the common heat-short by avoiding the stitch which is common to all layers, and preventing external exposure of any stitch to the outer environment. A unique overlap arrangement is described and additional protective methods are discussed
Miniature servo accelerometer is force- balanced
Miniature servo accelerometer measures unusually small forces of torques. The pendulous mass of the accelerometer is suspended by fused quartz torsion fibers in an electromagnetically force- balanced environment. It is used in gravity surveys for exploring mineral deposits
Light-direction sensor based on birefringency
Optical system consisting of polarizer, analyzer, quarterwave retarder converts incident light beam to one which has an intensity related to the extent the incident beam is off axis
An experiment in manipulator control with proximity sensors
Optical proximity sensors were used in a feedback loop to automatically position a manipulator hand for grasping. The experiment was a simplified one, involving two dimensional motion only. Two proximity sensors were mounted on the hand, and control signals derived from their outputs were used to drive the hand vertically and horizontally. The sensors employ a pulsed gallium arsenide light-emitting diode together with a silicon detector. They indicate, without contact, the approximate distance between the manipulator hand and object in the range from 5 to 12 cm. Positioning within approximately + or - 5 mm was observed. Extension of the technique to general three-dimensional control is briefly discussed
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