The Opticam spherical surface generator is developed at the Center for Optics Manufacturing (COM). It combines computer-numerical-control (CNC) technology with bound abrasive ring grinding geometry to create advantages over the conventional loose abrasive grinding systems in flexibility, productivity and accuracy. The Opticam SX utilizes a ring grinding geometry to generate spherical surfaces. By adjusting the tilt angle and the diameter of the ring cutter, the Opticam is capable of generating spherical surfaces with an essentially unlimited range of radius of curvature. This ring grinding geometry, however, requires a precise alignment between the cutter and the generated part. Residual cutter misalignments in the machine setup cause the finished surface to deviate from the design shape. Current tool misalignment detection techniques seriously limit the productivity of the Opticam system, and a new metrology system is introduced in this dissertation. The new system is geometrical ray trace based, and has some similarities to the moire deflectometry techniques. It uses a non-contact method to measure surface slope errors from images reflected off Opticam generated surfaces. The detected slope errors are used to determine the corresponding tool misalignments in the Opticam generator. The system setup is simple and not sensitive to vibrations. This system is compatible with the wet grinding environment. Furthermore, this new metrology system is capable of measuring surfaces with a wide range of radius of curvature from convex to concave. A prototype system was built based on this technique. It has been evaluated on-line in the Opticam SX. A surface wetting technique is used to allow detection on Opticam generated surfaces independent of the actual surface finish. The experimental results suggested that the on-line detection system is capable of detecting tool misalignment corresponding to a peak-to-valley surface figure error that is 1 mum or greater on ground surfaces. Better than 0.5 μm peak-to-valley surface error detection was achieved on specular surfaces. It was also found that machine dwell produces surface figure errors that are opposite to the errors produced by y-direction tool misalignment. Best surface figures are achieved when machine dwell errors are balance by residual tool misalignments in the Opticam machine.

In this work the problem of actuator and sensor mapping and controller design for the flexible structure control is approached as minimization of the residual deformations index (Hinfinity norm of the closed-loop disturbance - deformation path) over the set of non-destabilizing feedback controllers and over the set of possible actuator and sensor mappings. Computational load associated with this approach is reduced by restricting the search to the mapping areas where an inexpensive lower estimate of residual deformations index (derived as a part of this study) is less than the desired value of this index. Further improvement is achieved by including statistical description of the difference between the actual and the estimated performance index over the set of mappings, in order to adjust the level of the mapping acceptance/rejection in such a way that the number of rejected mappings is increased. Serial and parallel optimization procedures based on exhaustive search and genetic algorithms are discussed. These concepts and algorithms are applied to test cases of simply supported beam, the UCLA Large Space Structure, and a telescope mirror model: a hinged round plate.

The construction of lightweight manipulators with a larger speed range is one of the major goals in the design of well-behaving industrial robotic arms. Their use will lead to higher productivity and less energy consumption than is common with heavier, rigid arms. However, due to the flexibility involved with link deformation and the complexity of distributed parameter systems, modeling and control of flexible manipulators still remain a major challenge to robotic research. A compromise between modeling costs and control efficiency for real-time implementation is inevitable. The interdependency of subsystems results in a local optimal performance in the traditional design scheme. An important research topic in flexible manipulator design is the pursuit of better system performance while avoiding model-intensive or control-intensive work. This problem can be solved using the proposed mechatronic design approach. It treats the mechanical, electrical and control components of a flexible manipulator concurrently. The result is an improved design with an explicit link shape and controller parameters which result in the control problem and modeling accuracy no longer being critical for obtaining desired performance. Dynamics of flexible manipulators with rotatory inertia are derived, and state-space equations with the integration of DC motor dynamics are developed as a theoretical base for mechatronic designs. Two case studies based on LQR formula and Hinfinity control are considered. The beam shape and controller parameters are obtained using an adaptive iterative algorithm with the accommodation of various geometrical constraints. Also, different output feedback strategies are investigated to evaluate the impacts of various controller structures. Finally, a sensitivity analysis in terms of parameter variations and model uncertainties is conducted to reveal the robustness of this mechatronic design.

As organizations face stiff competition and changing environments their structure and systems can become less effective to a point at which they require radical change. It is becoming clear that change is often inevitable. However, radical change is difficult. The popular term "reengineering" is used to describe a process by which organizations undergo the challenging radical process change that is critical to remaining competitive. Although the processes of reengineering appears to have more potential than other change methods that merely tweak a poor system or apply outdated principles, it can often fail. A critical step in the reengineering process is the design of the "to-be" model, however no research has been done on how this should be achieved. It appears that improving this step can have a dramatic impact on the success of the reengineering effort as a whole. This study developed a method for creating "to-be" models and tested it with an organization undergoing reengineering. The method used the latest computer support including both group support systems and animated simulation. The design of the "to-be" models was framed as a group problem solving process and therefore the focus theory of group productivity was used to guide the design of the process, including selection of computer support tools. Because so little is known about the process of creating "to-be" models, this study used an exploratory action science approach. What is known about organizational change is that it takes place in a politically charged arena where individuals have strong vested interests in its outcomes. This environment is difficult to create in the laboratory and therefore the research was conducted using a real organization undergoing reengineering. Results suggest that the combined use of collaborative technology and process animation gives organization members a better understanding of current processes and problems associated with them and helps to generate significant ideas for process improvement. Because groups viewing a process animation have sometimes been observed to focus on incremental improvement at the expense of radical change, special attention must be given to facilitation methods and idea generation techniques that are designed to elicit radical change ideas.

On-line ultrasonic monitoring of injection molding of polyethylene and die casting of aluminum is studied using pulse-echo techniques. The flow front of molten materials including the polymers and aluminum inside the mold has been probed by a multiple-channel probing system with a time resolution of about 1 ms. This information can be used to control the plunger movements. The gap development which is important for the understanding of the thermal contact between the mold and the part due to the shrinkage is also monitored. Gap formation time periods versus different packing pressure and at different part locations with different part thickness have been investigated. The ultrasonic velocity inside the part during the solidification has been also measured for the interpretation of the solidification process. / For monitoring the die casting of aluminum with a melt temperature above 690°C, novel high performance buffer rods together with cooling channels are integrated into the die thus the ultrasonic measurement such as flow front and gap formation can be carried out with high signal-to-noise ratio signals for the first time at such elevated temperature.

The objectives of this thesis are to identify key safety concerns related to the introduction of automated underground mining machines. Second, a synthesis of existing standards, and guidelines is required to identify what existing safety standards or parts of standards could apply to mining machine automation systems. Finally, a framework is required for the development of a safety standard or guideline for automated mining machine systems. / Two workshops were organized and facilitated by the author to document as many identified safety concerns as possible from a range of parties with a vested interest. Workshop participants included mine operators, automated mining equipment suppliers, safety professionals, students, and academics. In addition, an analysis of underground mining equipment accidents for the province of Ontario was completed. A review of European, and North American safety standards was performed to identify those safety standards which could be used for mining machine automation systems. A synthesis of applicable safety standards is provided. (Abstract shortened by UMI.)

Many research and commercial environments need to measure fast time varying signals and need to control subsystems, e.g. actuators, also in real-time with high bandwidth and minimum latency. Existing commercial systems for data acquisition and control have many shortcomings and behave in a non-deterministic manner. Determinism or predictability is a key element of high performance real-time systems which must always meet specific deadlines under tight synchronizations. In this thesis, a new approach to very high-performance predictable real-time acquisition and control is proposed, theoretically analyzed, implemented in hardware, and experimentally tested. The resulting system is highly adaptable and reconfigurable, and has been applied to a number of problem areas including micro-robot control via a high performance parallel computer architecture, and cardiac electropotential mapping. Indeed, the resulting cardiac mapping system is so far as we know, the highest resolution produced to date.

<p> The purpose of this qualitative collective case study was to examine the perceptions and lived experiences of senior leaders of three different small-to medium sized manufacturing companies, located in the state of Colorado, as related to success strategies and barriers to lean manufacturing implementation. Findings resulted in nine emergent themes: (a) lean manufacturing implementation should be implemented in a way specific to the context of the individual organization; (b) time, resources, and changes in customer demand present challenges in sustaining lean manufacturing implementation; (c) resistance to change is a barrier to lean manufacturing implementation; (d) small-tomedium sized companies use outside consultants and trainers for training staff on lean manufacturing implementation; (e) front line workers need to be trained to apply lean tools and concepts for successful lean manufacturing implementation; (f) front line workers have to own and believe in lean manufacturing for it to be successful; (g) senior leaders have varying definitions of what their role is in leading lean manufacturing implementation; (h) senior leaders have differing perspectives regarding the degree of leadership knowledge required for successful lean manufacturing implementation; and (i) senior leaders struggle to expand lean manufacturing implementation into support departments. Recommendations included (a) viewing lean as a philosophy for managing the business, (b) training and education for senior leaders, (c) defining senior leader roles in implementing lean manufacturing, and (d) strategies when using outside consultants in a company&rsquo;s lean efforts.</p>

<p> Older adults are particularly vulnerable to poorly designed environments. The built environment and its perceptions can potentially support or discourage this growing cohort to engage in outdoor activities. Municipalities can uniquely promote physical activity for this targeted population through their planning and design processes. This research explored neighborhood perceptions of older adults and how differing perceptions influence their decision to walk. The results confirm that neighborhood perceptions vary across participants. Older adults from rural, suburban, and urban communities report significantly different perceptions. Perceptions also vary by socio-demographic characteristics. While walking activity does not significantly differ across neighborhood types, some environmental perceptions are associated with specific walking behaviors. These relationships also vary by neighborhood type and socio-demographic variables. Interviews with older women confirm the presence of physical, personal, social, and temporal barriers and motivators to walking. The focus on environmental perceptions in this research offers policy makers, urban planners, engineers, public works officials, and public health providers with findings and recommendations that specifically address walking in older adults, a growing population uniquely affected by the environment.</p>

<p> Growing concerns over the environmental and social impacts related to the production of clothing and textiles have created a need for more discussion about supply chain practices. Currently, there are no guidelines or strategies for addressing sustainable supply chains in the apparel industry that minimize environmental impacts and uphold socially responsible practices. This exploratory case study traces an apparel supply chain, with a focus on cotton, in South Africa that is under a development strategy to create a sustainable supply chain from farm to retail. In-depth interviews were conducted across the supply chain, including cotton farmers, cotton gins, a cotton yarn manufacturer, a textile mill, an apparel manufacturer, and a retailer. The purpose of the study was to gain an understanding of the business decisions at each node of the supply chain that influence the economic, social and environmental dimensions of sustainability by applying the triple top line model (McDonough &amp; Braungart, 2002). This study identifies strengths and weaknesses in sustainable practices that adhere to the triple top line model within each node of the supply chain. Results found economic factors were drivers for good social and environmental practices, with the latter being the smallest segment of the three. The study makes recommendations for improving practices at each node of the supply chain and recommendations for strategies for developing sustainable apparel supply chains.</p>