Recently, with the escalating demands for optical communications, the need for bandwidth in optical communication network has increased. The technology breakthrough indry fiber fabrication opens the possibility for fiber bandwidth form 1.3 to 1.6 £gm. Cr4+:YAG double-clad crystal fiber (DCF) grown by the co-drawing laser-heated pedestal growth method has a strong spontaneous emission spectum form 1.3 to 1.6 £gm. Such fiber is therefore, eminently suitable for optical coherence tomography (OCT), broadband optical amplifier, amplifier spontaneous emission (ASE) light source, and tunable solid-state laser applications. In this thesis, multilayer dielectric thin films were directly deposited by E-gun coating onto the end faces of the Cr4+:YAG DCF. To improve the thin-film quality, to increase transmittance of laser output, and to design for the high power laser. For broadband optical amplifier in dual-pump and double-pass scheme, a 3.0-dB gross gain, a 3.0-dB insertion loss, and a 0-dB net gain at 1.4-£gm signal wavelength have been successfully developed with HR coating onto one of the Cr4+:YAG DCF end faces. In addition, we have successfully developed the Cr4+:YAG DCF laser by direct HR coatings onto fiber end faces and increase transmittance of laser output. A record-low threshold of 31.2 mW with a slope efficiency of 7.5% was achieved at room temperature.

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Integrally heated composite tooling (IHCT) is seen as a low cost alternative to autoclave manufacturing of polymer matrix composites (PMCs). IHCTs consist of a composite tool heated by surface heaters; temperature distribution is ensured by a thermally conductive metallic layer. The main original contributions of this thesis was the development of a new method for applying copper coatings onto carbon fibre/epoxy PMCs using pulsed gas dynamic spraying, the production of larger size samples, and the characterisation of the performance of the coatings and laminates obtained. It was shown that this method has potential for producing the thermally conductive layer in an IHCT. Another contribution was the characterisation of parameters affecting temperature distribution across IHCTs through heat transfer simulations, leading to guidelines for IHCT design.

Integrally heated composite tooling (IHCT) is seen as a low cost alternative to autoclave manufacturing of polymer matrix composites (PMCs). IHCTs consist of a composite tool heated by surface heaters; temperature distribution is ensured by a thermally conductive metallic layer. The main original contributions of this thesis was the development of a new method for applying copper coatings onto carbon fibre/epoxy PMCs using pulsed gas dynamic spraying, the production of larger size samples, and the characterisation of the performance of the coatings and laminates obtained. It was shown that this method has potential for producing the thermally conductive layer in an IHCT. Another contribution was the characterisation of parameters affecting temperature distribution across IHCTs through heat transfer simulations, leading to guidelines for IHCT design.

With computer games getting more and more advanced with every year, game developers need to get creative to attract an audience. Throughout the years, tries has been made by moving away from the traditional gaming controller to enrich the gaming experience and to create a more healthy view upon the gaming industry. Most of these has involved the need of additional equipment to play the game, but what if all you need is the hardware in the computer? This report made findings in how to create a game that easily can be scaled by adding additional levels with custom tools for creation and modification in Unity. While only using the built-in web camera in the computer, it made it an accessible motion- based platformer game. This report also investigates the performance of the game when using these tools and the camera, as well as what is needed for improvements, including rendering and lighting effects in the game.

Surgical Tooling Designed for the Direct Anterior Approach to Total Hip Arthroplasty Jon-Peter Meckel Total hip arthroplasty (THA) is becoming more and more common in the US as people continue to live longer and more active lives. The main reason that a THA is required is due to the “wear and tear” affliction of osteoarthritis, which in the year 2000 had at least 3% of the population over 30 showing symptoms. A revitalized approach to THA is the direct anterior approach, or Smith-Petersen approach, which limits the amount of musculature affected by the surgery and creates a very stable joint post-operatively. While this approach is showing great clinical success, it does require slightly unconventional patient positioning. The pioneers of this surgical approach include Dr. Joel Matta, who along with Mizuhosi (Union City, CA, USA) has created an impressive direct anterior approach surgical table to address the problems associated with getting patients in the right position. Unfortunately, this table is very expensive, gives no feedback on force application, and surgeons are being taught that it is required to perform the procedure. This thesis introduces a simple set of surgical tooling that facilitates the direct anterior approach very cost effectively, giving the surgeon the feedback lacking in the expensive Mizuhosi table, and the flexibility to attempt the approach without convincing his or her hospital to make such a large capital investment. A prototype was successfully developed and tested to show that a simple solution exists to make the direct anterior approach more feasible for surgeons to incorporate into their practice.

The purpose of this research was to scientifically validate potential cost-saving measures for production of large area additively manufactured tooling for vacuum infusion of composites. These cost saving measures included using a hybrid additive/subtractive manufacturing system to fabricate the mold, requiring lower capital cost and creating shorter lead times. Fiberglass reinforcement was used instead of carbon in the mold material. The validation was done by designing and fabricating a mold for a custom test artifact and analyzing the surface geometry over the course of multiple infusions until tool failure.After printing and machining, the mold required a sealer in order to maintain vacuum integrity. The mold was able to produce 10 parts successfully before the sealed tool surface began to tangibly roughen, resulting in increased difficulty of demolding and a rougher surface finish. After the 14th infusion, the part required destructive force to be removed from the mold. The surface geometry remained consistent within ±0.5 mm of the design over the course of the infusions, and no significant trends in tool wear were observed during this time. In order to quantify the change in roughness, profilometry measurements were taken on the finished mold, and the measured area roughness value SA changed from 0.293 μm to 2.27 μm over the course of the infusions.Based on these results, it was concluded that an increase in surface adhesion is the principal mode of tool failure over the life of these tools. In addition, it was concluded that the minimum tool life for this combination of mold making methods and materials is 14 parts, as this result was obtained under an extreme case in abrasive part geometry and materials for vacuum infusion processing. Thus, this combination of methods and materials is suitable for prototyping of composite parts or short production runs.

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The recent manufacturing environment is characterized as having diverse products due to mass customization, short production lead-time, and unstable customer demand. Today, the need for flexibility, quick responsiveness, and robustness to system uncertainties in production scheduling decisions has increased significantly. In traditional job shops, tooling is usually assumed as a fixed resource. However, when tooling resource is shared among different machines, a greater product variety, routing flexibility with a smaller tool inventory can be realized. Such a strategy is usually enabled by an automatic tool changing mechanism and tool delivery system to reduce the time for tooling setup, hence allows parts to be processed in small batches. In this research, a dynamic scheduling problem under flexible tooling resource constraints is studied. An integrated approach is proposed to allow two levels of hierarchical, dynamic decision making for job scheduling and tool flow control in Automated Manufacturing Systems. It decomposes the overall problem into a series of static sub-problems for each scheduling window, handles random disruptions by updating job ready time, completion time, and machine status on a rolling horizon basis, and considers the machine availability explicitly in generating schedules. Two types of manufacturing system models are used in simulation studies to test the effectiveness of the proposed dynamic scheduling approach. First, hypothetical models are generated using some generic shop flow structures (e.g. flexible flow shops, job shops, and single-stage systems) and configurations. They are tested to provide the empirical evidence about how well the proposed approach performs for the general automated manufacturing systems where parts have alternative routings. Second, a model based on a real industrial flexible manufacturing system was used to test the effectiveness of the proposed approach when machine types, part routing, tooling, and other production parameters closely mimic to the real flexible manufacturing operations. The study results show that the proposed scheduling approach significantly outperforms other dispatching heuristics, including Cost Over Time (COVERT), Apparent Tardiness Cost (ATC), and Bottleneck Dynamics (BD), on due-date related performance measures under both types of manufacturing systems models. It is also found that the performance difference between the proposed scheduling approach and other heuristics tend to become more significant when the number of machines is increased. The more operation steps a system has, the better the proposed method performs, relative to the other heuristics. This research also investigates in what conditions (e.g. the number of machines, the number of operation steps, and shop load conditions) the proposed approach works the best, and how the performance of this proposed approach changes when these conditions change. When tooling resource is shared, parts can be routed to machines that do not have all the required tools. This may result in higher routing flexibility. However, research work to date in sharing of tooling resources often places more emphasis on the real-time control and manipulation of tools, and pays less attention to the loading of machines and initial tool allocation at the planning stage. In this research, a machine-loading model with shared tools is proposed to maximize routing flexibility while maintaining minimum resident tools. The performance of the proposed loading heuristic is compared to that of a random loading method using hypothetically generated single stage system models. The study result indicates that better system performances can be obtained by taking into account the resident tooling ratio in assigning part types and allocating tools to machines at the initial planning stage. / Ph. D.