Manufacturing & Prototyping

Wheel Design Verified With FEA Software

This paper examines an aluminum wheel design used with a run-flat tire called an extended mobility technology (EMT) tire, which can be safely driven without air for at least 80 km (50 miles). The setup of the finite element model of the wheel is discussed in detail, along with a parametric study of the inflation pressures and resulting stresses to verify that existing wheel designs could maintain the safety benefit of controlled handling and braking, even when the tire goes flat.

Posted in: Manufacturing & Prototyping, Briefs

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Constant-Differential-Pressure Two-Fluid Accumulator

An improved design does not rely on the spring rate of the accumulator tank.A two-fluid accumulator has been designed, built, and demonstrated to provide an acceptably close approximation to constant differential static pressure between two fluids over the full ranges of (1) accumulator stroke, (2) rates of flow of the fluids, and (3) common static pressure applied to the fluids. Prior differential-pressure two-fluid accumulators are generally not capable of maintaining acceptably close approximations to constant differential pressures.

Posted in: Manufacturing & Prototyping, Briefs

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Particle Distribution on Webs or Cloths

This technology provides the ability to uniformly distribute and attach particulate matter onto fibrous composite sheet or web materials.This technology provides a methodology and products that are formed from fibrous substrates or film-like surfaces by uniform impregnation with a particulate that is subsequently firmly attached. The extremely uniform distribution of the particulate is accomplished by 1) electrically charging a fibrous matrix with individual exposed surfaces to create a uniform distribution of charged sites; 2) applying particulates to this matrix so that particulates adhere at the charged sites; and 3) the particulates are attached to the individual fibers within the substrate by firm non-transient bonding.

Posted in: Bio-Medical, Manufacturing & Prototyping, Materials, Coatings & Adhesives, Medical, Briefs, MDB

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Photochemical Tissue Bonding for Military Medical Applications

A two-wavelength laser and albumen stent easily repair separated vessels.Joining severed vessels is a recurring problem in trauma and surgery. The basic technology of joining vessels using sutures has been available for centuries, but remains a slow and tedious process. A complete system for micro-anastomosis of vessels was developed that involves a laser in a clinically useful form factor, and a novel albumen stent to support the vessel during the surgery.

Posted in: Bio-Medical, Photonics, Manufacturing & Prototyping, Medical, Briefs, TSP, MDB

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Inflatable Tubular Structures Rigidized With Foams

Lightweight booms could be deployed from compact stowage and rigidized in place.Inflatable tubular structures that have annular cross sections rigidized with foams, and the means of erecting such structures in the field, are undergoing development. Although the development effort has focused on lightweight structural booms to be transported in compact form and deployed in outer space, the principles of design and fabrication are also potentially applicable to terrestrial structures, including components of ultralightweight aircraft, lightweight storage buildings and shelters, lightweight insulation, and sales displays.

Posted in: Manufacturing & Prototyping, Briefs

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Thermal-Stress Technique for Cutting Thin Glass Sheets

Highly localized heating generates highly localized stresses. A technique based on the generation of highly localized thermal stresses has been devised as a means of cutting both flat and curved glass sheets of thicknesses between 30 and 600 µm. The technique is reliable, accurate, and economical. The technique can be used, for example, to cut thin glass sheets for microscope slides and for covers on laptop-computer displays and other flat-panel displays.

Posted in: Manufacturing & Prototyping, Briefs

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Venting Closed-Cell Foam Panels

Stresses caused by differential gas pressures are reduced. A technique for reducing in-flight loss of closed-cell foam insulation has been devised. In the original application, foam is used for thermal insulation on the external tank of the space shuttle. As the space shuttle ascends, aerodynamic effects cause an increase in surface temperature of the foam. This heating increases the internal cell gas pressure and reduces cell wall strength. The difference between the increasing pressure of the gases trapped in the foam cells and the decreasing pressure of the ambient air contribute to stresses that can break off pieces of foam during flight. Perforating the foam with small holes makes it possible for some trapped gases to escape, reducing the stresses sufficiently to keep the foam intact during ascent. This technique reduced in-flight foam loss by more than 95 percent. The vent holes could offer similar benefits in other applications where materials are subjected to thermal and pressure gradients.

Posted in: Manufacturing & Prototyping, Briefs, TSP

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