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Showing papers by "Defence Research and Development Laboratory published in 1999"


Journal ArticleDOI
TL;DR: In this article, a composite liner of carbon phenolic has been inspected by ultrasonic, X-ray radiography and x-ray computed tomography (CT) to find defects like delaminations, debonds, voids, foreign inclusions, etc.
Abstract: A composite liner of carbon phenolic has been inspected by ultrasonic, X-ray radiography andX-ray computed tomography (CT) to find defects like delaminations, debonds, voids, foreign inclusions, etc.The geometry, detection of multiple defects and porosity of the liner make ultrasonic testing (pulse-echo anddrycoupling) difficult for inspection. X-ray radiography being a non-contact technique finds multiple defectsbut compresses the structural information of 3-D volume into a 2-D image and interferes with overlyingand underlying areas of the object. X-ray CT generates an image of a thin and cross-sectional slice ofan object. R e linear attenuation coefficients in terms of Hounsfield values have been measured, comparedand correlated with CT images at the contrasts observed. 3-D images can be generated by stacking2-D cross-sectional images of the slices. These 3-D images can be cut at any angle of choice for mappingthe extent of delaminated/debonded areas. This type of information is difficult to obtain with conventionalnon-destructive testing techniques.

1 citations


Journal ArticleDOI
TL;DR: In this article, a single-shot system with safety actuating mechanism (SAM) subsystem is proposed to provide safety during handling, launch and flight of a missile and actuatesthe warhead whenever desired on receiving of firing pulse from radio altitude switch.
Abstract: Development of high technology and high cost weapons system is a difficult task in view of. highreliability goals. It is further compounded in the case of single-shot airborne systems. Overall reliabilityof weapons system depends upon the reliability of systems and sub-systems used. Design of each systemand sub-system is fmalised after preliminary design review, critical design review, etc. and final reliabilityis demonstrated by subeing to functional tests.Warhead is the only sub-system responsible for inflicting damage to the target and all the otherembsystemsassist in delivering the warhead on or near the target. Safety actuating mechanism (SAM) subsystemis a single-shot device which provides safety during handling, launch and flight of a missile and actuatesthe warhead, whenever desired on receipt of firing pulse from radio altitude switch. SAM being critical forsuccessful detonation of the warhead, it is desired that this unit should have very high reliability. SAMunits are subjected to reliability tests and a reliability factor of 0.84 at 90 per cent confidence level is achievedwhich further increases to 0.98 due to redundancy.

1 citations