SBIR-STTR Award

The potential for structural failures in fuse assemblies on hardened-target penetrators results from both the high decelerations experienced and their short duration. Fuse survivability would be enhanced by lowering the magnitude, and extending the duration, of the deceleration pulse transmitted from the weapon to the fuse. LRK Associates proposes to model and analyze the shock-smoothing performance of a compliant material system that naturally smooths rise- and fall-times to reduce jerk, and then provides a constant, optimum deceleration lower than the shock peak in between. This latter level can be set by a simple mechanical adjustment. The system is passive, requiring neither electrical power nor logic, and should be constructible from commercially available materials. The system scales well to different fuse masses, and can be used during both impact deceleration and launch acceleration. Initial analysis predicts this system allows less than 20% of the fuse displacement produced by a damped linear system subject to the same maximum acceleration

Experimental tests in Phase I have shown the fuze shock absorber system capable of reducing shock peaks by a factor of three, and the associated jerk by an order of magnitude. The Phase II work will be devoted to exploring the performance space of this jerk-reduction system as a function of its material properties and physical configuration, as well as the fuze mass. LRK Associates will design and fabricate the various jerk-reduction test articles that will then be shock tested at AFRL, Eglin AFB. Analysis of the results of these tests will supply data to build an empirical performance model from which design rules can be stated. Following successful program review at the end of the first year, the second year will be devoted to designing, fabricating, and testing a realistic prototype jerk-reduction system applicable to a fuze/fuze well combination currently found in the inventory of Air Force ground penetrating weapons.

Keywords:
Fuze Survivability, Shock Absorption, Compliant Material, Optimum Deceleration, Shock Testing, Jerk Reduction