Panel-fastening systems rely on a combination of oversized structural holes and nut-element float to accommodate panel removal and installation. Improvements in positional tolerances of tooling used to produce interchangeable panels, makes a new Panel Aligning Fastener System (PAFS) feasible.
PAFS differs from common panel fastening systems in that the access panel and its mating structure are treated as a stiff-spring system in which each fastener loads/unloads the spring system a small amount. With PAFS "pinning'' panels in place, it should be possible to design and manufacture improved, lighter weight, more efficient structure using fewer fasteners. Other advantages:
All male fasteners for a given panel can be identical, regardless of substructure thickness
The fastening system eliminates bending moment failures in the threads
Receptacle has no moving parts for high reliability
Improved fastener flushness
Improved fuel sealing (gasket chafing eliminated)
Inherent low cost
Panel hole misaligned with structure hole
With > 3 threads engaged, fastener becomes a jackscrew
Fastener chamfer engages receptacle barrel
Major diameter of bolt moves into the shear plane
Jim Landgrebe, Lockheed Martin Tactical Aircraft Systems, MZ 4266, Box 748, Fort Worth, TX 76101; (817) 763-2113.
Samsung's Galaxy line of smartphones used to fare quite well in the repairability department, but last year's flagship S5 model took a tumble, scoring a meh-inducing 5/10. Will the newly redesigned S6 lead us back into star-studded territory, or will we sink further into the depths of a repairability black hole?
In 2003, the world contained just over 500 million Internet-connected devices. By 2010, this figure had risen to 12.5 billion connected objects, almost six devices per individual with access to the Internet. Now, as we move into 2015, the number of connected 'things' is expected to reach 25 billion, ultimately edging toward 50 billion by the end of the decade.
NASA engineer Brian Trease studied abroad in Japan as a high school student and used to fold fast-food wrappers into cranes using origami techniques he learned in library books. Inspired by this, he began to imagine that origami could be applied to building spacecraft components, particularly solar panels that could one day send solar power from space to be used on earth.
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