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Safety of satellites as well as spacecrafts during space missions is a primary objective to preserve the physical and virtual assets onboard. Whipple shields belong to the class of protective equipment provided on the surface of the spacecrafts and satellites, to sustain impacts from the ultra-high speed debris, which can otherwise cause considerable damage to the corresponding structures. Recent works on whipple shields are focussed on determining the response of different geometrical arrangements and material properties under hyper-velocity impact at projectile speeds of 3-18 km/s. Advances in the whipple shield design include integrated and mechanised models employing high performance materials like fiber-metal laminates ensuring better operational capability. The forward bumper of the whipple shield is the first line of defence as it regulates the state of projectile after the primary impact. Use of aluminium alloys for front bumpers is popular, owing to their lightweight and strength characteristics. The advances for the front bumper have seen usage of ceramic, metallic foams, and super composite mixtures, which resulted in enhanced performance, durability and safety of the whipple shields. This work is a comprehensive coverage of the latest materials used for whipple shields, their performance characterization—both experimental and theoretical, and applications.

Highway Development and Management (HDM-4) is comprised of decision-making tools used to assess the economic, social, and environmental viability of project development proposals to arrive at the best investment decisions. The entire system is built on various functions of pavement performing under numerous structural and environmental influences. The present work aims to study pavement distress and deteriorations prevailing on rural roads. At each stage, the road deterioration models predict impacts of distress at different rates and scenarios over each of the study sections. The analysis presents alternative maintenance and improvement strategies that could be implemented judiciously under scheduled or responsive routine assessments of road performance. Moreover, the analysis and output data for distress projection as obtained from HDM-4 is also validated from the existing pavement deterioration condition of the selected sections. The comparison of deterioration before and after works and the economic indicators delineated that Overlay for rural road sections is considered to be the most suitable alternative possible among others. Furthermore, the validation of the deterioration levels as predicted through HDM-4 indicates very low variation in the range of 2%-10% from the existing pavement deterioration levels. The results of this study are useful for developing pavement maintenance management strategies for rural roads network with similar characteristics.

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