Engineering topics

Collins, J. David

Publications and source records attributed to Collins, J. David.

3 records

NASA NTRS1995

Optoelectronic Instruments For Analysis Of Surface Defects

Family of portable optoelectronic instruments developed to facilitate inspection of surface flaws like gouges, scratches, raised metal, and dents on large metal workpieces subject to surface-finish requirements. Instrument brought to workpiece and semiautomatically makes electronic record of three-dimensional shape of flaw. Entire inspection process takes only minutes. Prototype instrument includes structured-light microscope. Concept involves projection of known pattern of light onto surface inspected. Topography of surface determined from distortion of pattern as viewed through instrument.

Collins, J. David↗

NASA NTRS1995

Optoelectronic Alignment And Ultrasonic Ranging Apparatus

Beam of light guides alignment, then range measured by use of ultrasound. Optoelectronic/ultrasonic apparatus facilitates three-dimensional alignment of spot on one object with respect to facing (but not touching) spot on another nearby object. Designed to help in positioning external tank of space shuttle between two solid rocket boosters. Useful in other applications to align large components to be locked together in assemblies.

Collins, J. David↗

NASA NTRS1993

Two-Band Pyrometers Detect Hydrogen Fires

Two-band infrared pyrometers detect small hydrogen fires at greater distances in full daylight being developed. Detectors utilize part of infrared spectrum in which signals from hydrogen flames 10 to the 3rd power to 10 to the 4th power times as intense as ultraviolet region of current detectors. Utilize low-loss infrared lenses for focusing and for limiting fields of view to screen out spurious signals from nearby sources. Working distances of as much as 100 meters possible. Portable, battery-powered unit gives audible alarm, in form of increase in frequency of tone, when aimed at hydrogen fire.

Collins, J. David↗