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This paper illustrates an effective application of rapid prototyping (RP) to produce a high definition polymer model of a satellite structure prior to final machining of the aluminum panels. The benefits when using this type of model in the design and assembly stages of satellite fabrication make clear that RP can and should play an important role in the design and fabrication of small satellite structures.

Selective laser sintering was utilized to produce a full‐scale model of a novel modular small satellite structure. This model was then used as a tool for quality control, fit check, assembly process verification, mock‐up, and as a model for manufacturing tooling design.

This case study illustrates that the use of RP to create a model early in the design cycle is beneficial from a cost and time perspective even when applied to a product which will be produced in a quantity of one. In addition, the merits of RP mesh well with modular designs and for applications where assembly and test tooling is required to validate the quality of a product.

This paper illustrates an effective use of RP in the satellite fabrication industry. The benefits described are generally applicable to other complex systems which need design validation early in the design cycle.

There are few examples of the effective application of RP to produce models, but not the final product, of a complex structure in the satellite and other industries where small lot production occurs.

The purpose of this paper is to explore the effect of different parameter configurations of oscillation amplitude, welding speed, and normal force at 478 K (400°F) on the linear welding density of stainless steel 316L annealed utrasonically consolidated (UC) samples, and present an optimum parameter set based upon maximum linear welding density criteria.

The paper describes the application of analysis of variance to different experimental designs in order to compare factor effects and obtain the optimum linear welding density parameter set for the ultrasonic consolidation of stainless steel 316L annealed samples.

This work includes experimental results at assessing the explained variation due to factor effects on linear welding density, the statistical significance of these factors, and the combination of UC process parameters that maximizes linear welding density in stainless steel 316L annealed samples.

The paper presents results obtained with a specific UC system, a standard sample configuration, and relatively constant frictional conditions.

This work is a first step towards a reproducible UC of stainless steel 316L foils with high linear welding density.

There has been little thought given in science to the impact of direct brain‐machine interfacing upon the future development of human consciousness. Even less thought has been given to the possibilities for both optimizing and thwarting development in the cyborg child. A neurocognitive model of the evolution of cyborg consciousness is summarized, and from this model grounded speculations are offered pertaining to the future development of the higher cognitive functions in the cyborg child. It will be shown that cybernetic implants are “multistable”; that is, the artificial intelligence (AI) component of the cyborg brain‐machine linkage may function to condition development along ideological lines (the brain conditioned by the “ideological chip”), or may operate to open up neurocognitive development to new and heretofore unrealized limits (the brain’s development optimized by the “guru programme”). Development of the cyborg child may be conditioned in the interests of ideological concerns, or may lead to a consciousness that easily transcends all forms of ideology. Application of the guru programme may foster the emergence of new levels of cognitive complexity and information processing (à la Piagetian and neo‐Piagetian theory) that in turn allows new strategies of adaptation previously beyond human comprehension. The ethical and regulatory problems raised by cyborg technologies are addressed.

The purpose of this paper is to explore how flourishing is achieved among sport employees working at intercollegiate sport organizations in the USA. To do so, a model is constructed that examines the impact of pride and path-goal leadership on job engagement and then flourishing. The model is grounded in the Human Resource Development (HRD) paradigm to extend the literature on positive performance outcomes in sport organizations.

Quantitative methods were used to analyze the data. Altogether, 282 useable surveys were completed by sport employees working in intercollegiate athletics departments. The hypotheses were examined with structural equation modeling to provide robust calculations of the relationships within the model.

The findings of this study demonstrated that both path-goal leadership and pride enabled job engagement, which in turn supported flourishing among intercollegiate athletics employees (e.g. equipment, marketing or facility/event positions). Job engagement is positioned as an important variable as it linked path-goal leadership and pride with flourishing.

This study examined mechanisms (i.e. path-goal leadership, pride) to enhance intercollegiate athletics employees' personal resources (i.e. job engagement, flourishing) through the HRD paradigm. The HRD framework posits that improved employee functioning leads to a superior organizational performance and has yet to be assessed within intercollegiate athletics. The findings add to the HRD literature by focusing on employees' workplace experiences and generating pathways to improved job engagement and the subsequent influence on intercollegiate athletics employees' ability to flourish, which is also understudied.

The increasing interest in engineering structures made from multiple materials has led to corresponding interest in technologies, which can fabricate multi‐material parts. The purpose of this paper is to further explore of the multi‐material fabrication capabilities of ultrasonic consolidation (UC).

Various combinations of materials including titanium, silver, tantalum, aluminum, molybdenum, stainless steel, nickel, copper, and MetPreg^® were ultrasonically consolidated. Some of the materials were found to be effective as an intermediate layer between difficult to join materials. Elemental boron particles were added in situ between selected materials to modify the bonding characteristics. Microstructures of deposits were studied to evaluate bond quality.

Results show evidence of good bonding between many combinations of materials, thus illustrating increasing potential for multi‐material fabrication using UC.

Multi‐material fabrication capabilities using UC and other additive manufacturing processes is a critical step towards the realization of engineering designs which make use of functional material combinations and optimization.

Recently, a number of research projects have been focused on an emerging additive manufacturing process, termed ultrasonic consolidation (UC). The purpose of this paper is to present an analytical energy model aimed at investigating the effects of process parameters on bond formation in UC.

In the model, two factors are defined, energy input to the workpiece within a single cycle of ultrasonic vibration (E₀) and total energy input to the workpiece (E_t), to evaluate to the magnitude of transmitted energy into the workpiece during UC.

It is found that linear weld density, E₀ and E_t are affected by process parameters in similar manners.

The current model is developed based on several simplifying assumptions, and energy dissipation and bond degradation during UC are not considered in the model.

The current model gives a useful understanding of the effects of process parameter on the bond formation in UC from an energy point of view.

Rapid prototyping (RP) techniques are being increasingly used to manufacture injection molding and die casting core and cavity sets, known as tools, and for other tooling‐related parts, such as EDM electrodes. This paper presents a STL‐based finish machining technique for tools and parts made using RP techniques in order to achieve the tight tolerance and surface finish requirements necessary for tooling applications. Rotate, scale, translate and offset algorithms are used to pre‐process the 3D model prior to its manufacture. A machining strategy of adaptive raster milling of the surface, plus hole drilling and sharp edge contour machining, is developed to finish the parts and tools after fabrication using RP. Finally, a benchmark part was designed and fabricated using the above‐mentioned strategies and the results show the effectiveness of the developed software.

This paper investigates wetting and infiltration of zirconium diboride by copper and copper/boron alloys in order to more effectively create electrodes for electrical discharge machining.

A high temperature furnace outfitted with a video recording system was utilized to observe wetting angles between molten copper alloys and zirconium diboride at various temperatures. A parallel, investigation of the thermodynamics involved with oxidation in the system was also undertaken.

This study showed that zirconium diboride can be wet by pure copper under carefully controlled conditions where oxygen contamination is minimized, and that the wetting angle increases with increasing temperature. Thermodynamic calculations reinforce the contention that oxygen contamination is the key barrier to wetting and infiltration. The addition of boron to copper significantly improves the wetting characteristics, and enables wetting and infiltration under higher oxygen contamination conditions.

This study illustrated that boron must be added to copper to achieve infiltration when surface oxides are present.

Infiltration of porous 3D green shapes of ceramics and metals is a common method for producing metal and ceramic components using rapid prototyping. Good wetting of the porous material by the infiltrant material is necessary for successful infiltration using capillary forces. This paper illustrates the alloys and conditions under which it is possible to produce electrodes of zirconium diboride/copper using rapid prototyping.

This paper presents a new 3D offset method for modifying CAD model data in the STL format. In this method, vertices, instead of facets, are offset. The magnitude and direction of each vertex offset is calculated using the weighted sum of the normals of the facets that are connected to each vertex. To facilitate the vertex offset calculation, topological information is generated from the collection of unordered triangular facets making up the STL file. A straightforward algorithm is used to calculate the vertex offset using the adjoining facet normals, as identified from the topological information. This newly developed technique can successfully generate inward or outward offsets for STL models. As with any offset methodology, this technique has benefits and drawbacks, which will be discussed in this paper. Finally, conclusions will be made regarding the applicability of the developed methodology.

This paper presents an offset‐based tool path generation method for STL format three‐dimensional (3D) models. The created tool‐paths can be effectively used to near‐net‐shaped parts, in particular those created using rapid prototyping.

The STL model is first offset by the distance of the selected cutter radius using a unique 3D offset method. The intersections between the top facing triangles of the offset model and tool‐path drive planes are calculated. The intersection line segments are sorted, trimmed and linked to generate continuous top envelope curves, which represent interference‐free tool paths.

The developed offset‐based algorithm can rapidly and successfully generate interference‐free tool paths as continuous lines, instead of a collection of discrete tool location points. The strategy of using adaptive step‐over distances based on local geometrical information can significantly increase machining efficiency.

The current tool path generation method only works for ball‐end mills. The entire surface of the STL model is treated as a single composite surface to be machined using raster milling. To improve machining efficiency, an automatic surface splitting algorithm could be developed to divide the model into several regions based on the characteristics of a group of triangular facets, and then machine these identified regions using different strategies and cutters.

The offset‐based tool‐path generation algorithm from STL models is a unique and novel development, which is useful in the rapid prototyping and computer‐aided machining areas.