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Die-based forming is a technology used by many industries to form metal panels. However, this method of forming lacks flexibility and cost effectiveness. In such cases, manual panel beating is typically undertaken for incremental forming of metal panels. Manual panel forming is a highly skilled operation with very little documentation and is disappearing due to non-observance and a lack of interest. Confederation of British Metal forming (CBM) and Institution of Sheet Metal Engineering (ISME) have realised the need for capturing and understanding manual skills used by panel beaters to preserve the knowledge. At the same time, industries seek for alternative panel forming solutions to produce high quality and cost-effective parts at low volume and reduce the repetitive, yet adaptive parts of the panel forming process to free up skilled workers to concentrate on the forming activities that are more difficult to automate. Incremental forming technologies, currently in practice, lack adaptability as they require substantial fixtures and dedicated tools. In this research a new proof-of-concept fixtureless automated sheet metal forming approach was developed on the basis of human skills captured from panel beaters. The proposed novel approach, named Mechatroforming®, consists of integrated mechanisms to form simple sheet metal parts by manipulating the workpiece using a robotic arm under a repetitive hammering tool. Predictive motion planning based on FEA was analysed and the manual forming skills were captured using a motion capture system. This facilitated the coordinated hammering and motion of the part to produce the intended shape accurately. A 3D measurement system with a vertical resolution of 50μm was also deployed to monitor the formation of the parts and make corrections to the forming path if needed. Therefore, the developed mechatronic system is highly adjustable by robotic motion and was closed loop via the 3D measurement system. The developed automated system has been tested rigorously, initially for bowl shape parts to prove the principle. The developed system which is 98% repeatable for depth and diameter, is able to produce targeted bowl shape parts with ±1% dimensional accuracy, high surface quality, and uniform material thickness of 0.95mm when tested with aluminium. It is envisaged that by further research, the proposed approach can be extended to form irregular and more complicated shapes that are highly in demand in various industries.

The rapid progress of the Asia-Pacific rim countries during the past three decades has attracted world-wide attention, especially in the field of technological innovation. By the mid 1980's, researchers had acknowledged that the Asia-Pacific rim region had redefined the global balance of competition while at the same time, the western nations were suffering a decline in world market share. The perspective of the Asia-Pacific rim thinking tends to gravitate towards an endogenous model, where factors are more amenable to the influence of the organisation. An investigation by the World Bank on East Asia (including Japan, Korea, Taiwan, Singapore and Hong Kong) has uncovered emphatic evidence that the three dimensions propounded by Ohmae's model of people,finance and assets have been instrumental in enabling these economies "to acquire and master technology".This research explores the philosophy and strategic thinking of the Asia-Pacific rim electronics manufacturing industry with respect to the determinants of technological innovation. The study is divided into three major phases. The initial phase examines the respective strands of literature pertaining to the strategic issues of technological innovation. Special attention has been focused on the functional utilisation of people,finance and assets within the perspective of the Asia-Pacific rim electronics industry, leading to a broad-based framework for the study. Phase two is comprised of two main activities: the first involves exploratory interviews with four notable electronics companies and the second has entailed the gathering of data from 111 companies within the five Asia-Pacific rim countries (Japan, Korea, Singapore, Taiwan and Hong Kong) operating in Singapore and the United Kingdom, by means of a mailed questionnaire survey. Phase three involves qualitative as well as quantitative analyses where statistical methods such as one-way ANOVA, Chi-square test and t-tests have been undertaken to verify the data gathered from the primary research. The findings have uncovered that there are several determinants that are associated with the high rate of successful technological innovation in the sampled companies. For the people's dimension, there has been a high emphasis on training, resulting in a "nurtured" model of a worker, where numerous process innovations have been initiated by trained shop-floor technicians and engineers. At group working levels, various discussion groups (such as quality control circles and productivity discussion groups) have given rise to a collective learning process where shared knowledge enabled new products and processes to be innovated more rapidly than in the conventional departmentalised models. Other aspects of group dynamics has been the continuity (or smooth transition of innovative ideas) and good communications between functional groups thus acceleratingtechnological innovation. For the assets' dimension, the strategic foci have been shifted toautomation, flexible manufacturing process and increasing usage of information technology (including both computer hardware and software) so that new products can be brought to the market faster through the intelligent deployment of such assets and know-how. Finally, funds were found to have been allocated to expedite innovation through investment in R & D and staff training.

The work presented in this thesis attempts to improve the performance of industrial robot systems in a flexible manufacturing environment by addressing a number of issues related to external sensory feedback and sensor integration, robot kinematic positioning accuracy, and robot dynamic control performance. To provide a powerful control algorithm environment and the support for external sensor integration, a transputer based open architecture robot controller is developed. It features high computational power, user accessibility at various robot control levels and external sensor integration capability. Additionally, an on-line trajectory adaptation scheme is devised and implemented in the open architecture robot controller, enabling a real-time trajectory alteration of robot motion to be achieved in response to external sensory feedback. An in depth discussion is presented on integrating a stereo vision sensor with the robot controller to perform external sensor guided robot operations. Key issues for such a vision based robot system are precise synchronisation between the vision system and the robot controller, and correct target position prediction to counteract the inherent time delay in image processing. These were successfully addressed in a demonstrator system based on a Puma robot. Efforts have also been made to improve the Puma robot kinematic and dynamic performance. A simple, effective, on-line algorithm is developed for solving the inverse kinematics problem of a calibrated industrial robot to improve robot positioning accuracy. On the dynamic control aspect, a robust adaptive robot tracking control algorithm is derived that has an improved performance compared to a conventional PID controller as well as exhibiting relatively modest computational complexity. Experiments have been carried out to validate the open architecture robot controller and demonstrate the performance of the inverse kinematics algorithm, the adaptive servo control algorithm, and the on-line trajectory generation. By integrating the open architecture robot controller with a stereo vision sensor system, robot visual guidance has been achieved with experimental results showing that the integrated system is capable of detecting, tracking and intercepting random objects moving in 3D trajectory at a velocity up to 40mm/s.

The work reported in this thesis describes research carried out into the detailed design and operation of Flexible Machining Cells (FMC) incorporating automated work and tool flow, dual flow. Three modes of cell management are considered for dual flow cells, where the author examines both their operational and economic performance. A framework is defined for investigating these dual flow cells, and a structured approach providing a novel and detailed modelling capability is described. The question of how this approach compares to single flow modelling and the additional or alternative requirements for dual flow modelling is examined via the following key areas; the specification of material handling requirements, tool transportation and issue and finally, the control required to examine the interaction between the two flows operating concurrently. The framework is tested for its industrial applicability via an industrial case study. A major aim of this study is to examine the view that a hybrid cell management strategy, competitive management, could outperform the other strategies examined. The aim of this methodology is to provide a solution for the control of FMCs. Emphasis is placed on the ease of control and how the loading and control rules selection can maximise economic enhancement of a cells performance.

This qualitative study was written to expand the understanding of the potential sustainable use of activity-based costing in a small flexible manufacturing environment. The research was designed as a multiple-site case study, targeting two diverse small manufacturers in this market segment. Information was gathered to develop an understanding of how these firms cost their products, captured base manufacturing data, and the impact their leadership had on the management of costing processes. The information was gathered from documents received and observations on the shop floor at each participant site. In addition, participants from different functions either directly impacting or indirectly influencing the costing processes were interviewed at each site. The common theme at both locations was the minimal level of management accounting knowledge beyond the individuals directly tasked with the maintenance of the costing process. The other two topic themes discussed the way the firms collected production data. The interpretation of the findings by the researcher noted the strong influence of the market and profitability constructs on the leadership’s openness to change. This study will assist practitioners in emphasizing the need to understand the corporate environment before initiating any costing process change. Further research on possible optimum organizational size for the initiation of developing complex costing processes was encouraged, as the need to gain more accurate data is balanced against the day-to-day operational demands of the manufacturer. In addition, the findings noted the need to expand management accounting knowledge outside the accounting function to assist firms in understanding the impact of their actions and the impacts of process improvement initiatives. Key words: Flexible manufacturing, activity-based costing, management accounting.

The current manufacturing paradigm is shifting toward more flexible manufacturing systems that produce highly personalized products, adapt to unexpected disturbances in the system, and readily integrate new manufacturing system technology. However, to achieve this type of flexibility, new system-level control strategies must be developed, tested, and integrated to coordinate the components on the shop floor. One strategy that has been previously proposed to coordinate the resources and parts in a manufacturing system is multi-agent control. The manufacturing multi-agent control strategy consists of agents that interface with the various components on the shop floor and continuously interact with each other to drive the behavior of the manufacturing system. Two of the most important decision-making agents for this type of control strategy are product agents and resource agents. A product agent represents a single product and a resource agent represents a single resource on the plant floor. The objective of a product agent is to make decisions for an individual product and request operations from the resource agents based on manufacturer and customer specifications. A resource agent is the high-level controller for a resource on the shop floor (e.g., machines, material-handling robots, etc.). A resource agent communicates with other product and resource agents in the system, fulfills product agent requests, and interfaces with the associated resource on the plant floor. While both product agents and resource agents are important to ensure effective performance of the manufacturing system, the work presented in this dissertation improves the intelligence and capabilities of product agents by providing a standardized product agent architecture, models to capture the dynamics and constraints of the manufacturing environment, and methods to make improved decisions in a dynamic system. New methods to explore the manufacturing system and cooperate with other agents in the system are provided. The proposed architecture, models, and methods are tested in a simulated manufacturing environment and in several manufacturing testbeds with physical components. The results of these experiments showcase the improved flexibility and adaptability of this approach. In these experiments, the model-based product agent effectively makes decisions to meet its production requirements, while responding to unexpected disturbances in the system, such as machine failures or new customer orders. The model-based product agent proposed in this dissertation pushes the fields of manufacturing and system-level control closer to realizing the goals of increased personalized production and improved manufacturing system flexibility.

Human-robot interaction (HRI) is vastly addressed in the field of automation and manufacturing. Most of the HRI literature in manufacturing explored physical human-robot interaction (pHRI) and invested in finding means for ensuring safety and optimized effort sharing amongst a team of humans and robots. The recent emergence of safe, lightweight, and human-friendly robots has opened a new realm for human-robot collaboration (HRC) in collaborative manufacturing. For such robots with the new HRI functionalities to interact closely and effectively with a human coworker, new human-centered controllers that integrate both physical and social interaction are demanded. Social human-robot interaction (sHRI) has been demonstrated in robots with affective abilities in education, social services, health care, and entertainment. Nonetheless, sHRI should not be limited only to those areas. In particular, we focus on human trust in robot as a basis of social interaction. Human trust in robot and robot anthropomorphic features have high impacts on sHRI. Trust is one of the key factors in sHRI and a prerequisite for effective HRC. Trust characterizes the reliance and tendency of human in using robots. Factors within a robotic system (e.g. performance, reliability, or attribute), the task, and the surrounding environment can all impact the trust dynamically. Over-reliance or under-reliance might occur due to improper trust, which results in poor team collaboration, and hence higher task load and lower overall task performance. The goal of this dissertation is to develop intelligent control algorithms for the manipulator robots that integrate both physical and social HRI factors in the collaborative manufacturing. First, the evolution of human trust in a collaborative robot model is identified and verified through a series of human-in-the-loop experiments. This model serves as a computational trust model estimating an objective criterion for the evolution of human trust in robot rather than estimating an individual's actual level of trust. Second, an HRI-based framework is developed for controlling the speed of a robot performing pick and place tasks. The impact of the consideration of the different level of interaction in the robot controller on the overall efficiency and HRI criteria such as human perceived workload and trust and robot usability is studied using a series of human-in-the-loop experiments. Third, an HRI-based framework is developed for planning and controlling the robot motion in performing hand-over tasks to the human. Again, series of human-in-the-loop experimental studies are conducted to evaluate the impact of implementation of the frameworks on overall efficiency and HRI criteria such as human workload and trust and robot usability. Finally, another framework is proposed for the cooperative manipulation of a common object by a team of a human and a robot. This framework proposes a trust-based role allocation strategy for adjusting the proactive behavior of the robot performing a cooperative manipulation task in HRC scenarios. For the mentioned frameworks, the results of the experiments show that integrating HRI in the robot controller leads to a lower human workload while it maintains a threshold level of human trust in robot and does not degrade robot usability and efficiency.

We consider the allocation of reconfigurable resources in a serial manufacturing line with machine failures. The objective is to develop resource allocation policies that decrease inventory holding costs and increase average throughput. Each station is equipped with non-idling dedicated servers while the whole system is equipped with a finite number of reconfigurable servers that are available to be assigned to any station. In a two station clearing system (without external arrivals) both with and without machine failures, we show the existence of an optimal monotone policy. Moreover, when all of the machines are reliable, the switching curve defined by this policy has slope greater than or equal to -1. This continues to hold true when the holding cost rate is higher at the first stage and machine failures are considered. In systems with external arrivals, we provide conditions for a policy to achieve throughput optimality. We also show in the two-station case that transition monotone optimal policies exist. We develop two-pairing heuristics for n-station production systems based on the transition monotone properties in two-station models. To date, most dynamic resource allocation research considers only two stations and less than two flexible servers. None of this research includes server reliability considerations. Our research shows the optimality of monotone control policies in systems with multiple servers and reliability considerations. Based on the optimality of monotone control policies, the two-pairing heuristics allow problems of practical dimension to be decomposed into sub-problems that can be solved as Markov Decision Processes and reduce average holding costs significantly. These heuristics are compared to several heuristics from the literature via a detailed numerical study. Compared to other dynamic resources allocation policies, the two-pairing heuristics create lookup tables for decision makers and no additional computation is required in daily operation.

The challenge of making operational decisions in the face of a varying service capacity has both a historical and a contemporary significance. In manufacturing systems, it has long been known that making sound machine maintenance and replacement decisions can greatly improve the efficiency of the system. At the same time, a dynamic workforce due to priorities elsewhere in the system presents new and difficult decision-making scenarios. In this thesis we present new insights into these problem areas. The agile, temporary workforce problem models the phenomenon of floaters: agile workers (or machines) that can be dynamically reassigned to alleviate congestion in the system. Considered is a two-station tandem queueing system. Neither queue is equipped with dedicated servers. Instead, three scenarios for the fluctuations of workforce level are considered. In the first, a decision-maker can increase/decrease the capacity as deemed appropriate; the unrestricted case. In the other two cases, workers arrive randomly and can be rejected or allocated to either station. In one case the number of workers can then be reduced (the controlled capacity reduction case). In the other they leave randomly (the uncontrolled capacity reduction case). Under server collaboration assumptions, it is shown that in each scenario all workers should be allocated to one queue or the other (never split between queues) and that they should serve exhaustively at a particular queue according to an index rule. This extends previous studies on flexible systems to the case where the capacity varies over time. In the unrestricted case it is then shown that the optimal number of workers is non-decreasing in the number of customers in either queue. In the other cases, the optimal capacity increase/decrease decisions may not be monotone in the number of workers. The machine maintenance problem considers one server that deteriorates over time and has a reduction in productivity. The decision-maker decides when to perform maintenance, which may be done preemptively before catastrophic failures. Similar to classic maintenance models, the information available to the decision-maker includes the deterioration state of the server, s. Unlike classic models, the information also includes the number of customers in the queue, q. Considered are both repair models, with random repair times, and replacement models, with fixed costs but instantaneous repairs. It is shown in general that the optimal maintenance policies are monotone in s. Surprisingly, the switching-curve policies for the repair model are not always monotone in q.

Formation of part and machine cells with consideration of alternative process plans

The purpose of this study was to develop a selection model to be used in the design of packages for flexible manufacturing. The model was developed by utilizing the concepts and philosophies of Just-In-Time (JIT), Total Quality Control (TQC), and Design For Assembly (DFA). A case study was used to demonstrate the model. The case study involved the design of a new package for an existing product utilizing the concepts as previously outlined. Reduced part count, use of standard materials, configurations and process, and process flow charting were all key components of the selection model. As flexible manufacturing becomes a bigger part of the packaging industry, package designs which readily lend themselves to flexible manufacturing will become very important. The model developed in this study is aimed at helping the package designer quanitifiably select package structural designs which will lend themselves to a flexible manufacturing process.