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Automated industrial Visual Inspection Systems (VIS) are typically customized for specific applications, limiting their flexibility. They are characterized by a demanding setup, high capital investments, and significant knowledge barriers. In this paper, we propose an alternative architecture for the visual inspection of 3D printed parts or complex assemblies using a robotic arm equipped with hand-eye sensors and controllable lighting system. The core of the proposed Flexible Vision Inspection System (FVIS) is the self-extraction of 3D text annotations from STandard for the Exchange of Product model (STEP) AP242 files. The system self-selects and parametrizes the most suitable inspection algorithm, including lighting settings. Additionally, it autonomously performs self-localization, self-referencing of physical products, and self-planning of robot inspection path based on CAD information. This framework, characterized by self-X, cost-effective, non-invasive, and plug-and-play architecture has the potential to disrupt the business model of vision inspection, enabling an as-a-service solution aligned with the next generation of flexible manufacturing., QC 20240430

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.

Kundanpassade produkter och korta produktionsserier blir alltmer populärt. Detta har lett till problem för dedikerade tillverkningssystem som är designade för massproduktion. Det krävs ofta långa produktionsserier för att det ska bli en rimlig investering att ställa om produktionen. Därför används människor för tillverkningsuppgifter som ofta ställs om. Denna avhandling fokuserar på konceptet Plug & Produce, som gör det enklare att flytta, lägga till och ta bort resurser från ett tillverkningssystem. Tanken är att resurser placeras i processmoduler som alla har samma fysiska gränssnitt för att kopplas in i tillverkningssystemet. Styrningen av tillverkningssystemet görs av ett multiagentsystem där varje detalj som ska produceras för produkter får en egen agent som representerar detaljen och agerar som styrningsmjukvara. Varje detaljs agent tar hand on sina egna tillverkningsmål genom att kommunicera med resursagenter i systemet som används för styrning av resurserna. I detta arbete, presenteras ett ramverk för Plug & Produce som består av ett konfigurerbart multiagentsystem, samt ett konfigurationsverktyg som kan användas för att definiera agenterna. Arbetet inkluderar metoder för att identifiera inkopplade resurser, kommunikation mellan agenter, schemaläggning som kan undvika konflikter mellan agenter, samt metoder för att automatiskt hitta vägar för transport genom tillverkningssystemet., Customized products and low-volume production are becoming more popular resulting in a problem for dedicated manufacturing systems that are designed for mass production. Adapting a system to new demands is expensive and requires many products to be produced before it becomes a reasonable investment. This has forced factories to use human workers for manufacturing tasks that often change. This thesis focuses on a concept called Plug & Produce, which makes it easier to move, add, and remove resources in manufacturing systems. This is done by containing resources in process modules that all have the same physical connectors. To handle the control of the manufacturing system a multi-agent system is considered where each part to be produced for products has a part agent software running that represents that part. Each part agent takes care of their own manufacturing goals by communicating with resource agents that control the resources in the system. In this thesis, a Plug & Produce framework is describedthat consists of a configurable multi-agent system, together with a configuration tool for defining agent behaviours. Methods for identifying the resource that has been connected to a Plug & Produce system are investigated. Communication between agents in Plug & Produce is investigated. Scheduling is described for the presented systems to avoid conflicts when running multiple agents. Also, a pathfinding method for Plug & Produce is presented, which automatically gathers the necessary information for finding paths to transport parts through the manufacturing system., Paper E and F is to be submitted and not included in the electronic thesis.

The component layout problem requires efficient search of large, discontinuous spaces. Theefficient layout planning of a production site is a fundamental task to any project undertaking. This paper describes a genetic algorithm (GA) to solve the problem of optimal facilities lay out in manufacturing system design so that material-handling costs are minimized. The performance of the proposed heuristics tested over problems selected from the literature. Computational results indicate that the proposed approach gives better results compared to many existing algorithms in this area.

The shift towards electro mobility has a significant impact on the entire value chain of the automotive industry. The parallel production of Internal Combustion Engine, Battery Electric and Plug-in Hybrid Electric Vehicles con-fronts manufacturers with major challenges. This requires flexible production systems that are able to operate efficiently even under the influence of dynamic conditions. As could be seen in the COVID-19 pandemic, production systems must be able to react flexible and resilient even to these kinds of situations. Within the production system there is a multitude of temporally and spatially determined neuralgic points at which a reaction to dynamic conditions is possible and necessary. In order to make target-oriented decisions at these points, a large amount of data from many different sources is required as input parameters. The decisions can be made manually, semi-automatically or automatically by a human, a machine or a (software) system. Therefore it is essential that influences, input and output variables as well as decisions and the solution space are provided in a defined manner enabling all involved units to process the information. The paper therefore describes the first steps in modeling decisions for dynamic line-less assembly systems. Starting with an introduction to the topic and the multi-variant automotive production, the architecture of this kind of flexible assembly system is briefly described. Afterwards a description of the formal modeling of decisions in assembly systems is presented. Finally, after a discussion of the results, an outlook on the next steps and further research needs is given.

Energy efficient synthesis providing high quality crystalline thin films are highly desired in many applications. Here we devise a non-toxic solvent approach for production of highly crystalline MAPbI3 perovskite by exploiting diffusion aggregation processes. Isopropanol solution based methylammonium lead triiodide (MAPbI3) is used in this context, where the crystal growth initiation starts in an unstable suspension far from equilibrium and the subsequent crystallization is driven by the solubility parameters. The crystal formation is monitored by scanning transmission electron microscope (STEM), observing small crystallization centers growing as time evolves to large grains with high crystal purity. Energy dispersive X-ray spectroscopy (EDS) in STEM mode revealed a Pb rich core-shell structure in newly formed grains. Nano-beam Electron Diffraction (NBED) scan defined PbI2 crystallites in the Pb rich shell with a single crystal MAPbI3 core in newly formed grains. After a week stirring, the same aggregated suspension exhibited grains with only single crystal MAPbI3 structure. The NBED analysis shows a kinetically slow transition from a core shell structure to a single crystal grain. This research presents an impactful insight on the factors that may cause sub-stoichiometric grain boundary effects which can influence the solar cell performance. In addition, the structure, morphology and optical properties of the perovskite grains have been presented. A powder of highly crystalline particles was subsequently prepared by evaporation of the solvent in a low-vacuum oven. Thin film MAPbI3 solar cells were fabricated by dissolving the powder and applying it in a classical fabrication route. The MAPbI3 solar cells gave a champion efficiency of 20% (19.9%) and an average efficiency at approximately 17% with low hysteresis effects. Here a strategy to manufacture the material structure without toxic solvents is highlighted. The single-crystal growth devised here opens both for, QC 20201230

The manufacturing industry is shifting towards smart manufacturing, in which both energy efficiency and flexibility are some of the main objectives of this digital transformation. In this regard, the control strategies for manufacturing systems should be able to support the requirements of this transformation with a low computational burden towards their implementation in real time. To this end, in this paper, a dual mode control strategy based on two control approaches is proposed to minimise the energy consumption of manufacturing systems without affecting their productivity, even when scenarios of flexible manufacturing are considered. The first control mode is based on model predictive control to determine an optimisation-based strategy for the constrained behaviour of the system. Then, the second mode builds on the assumption that the system exhibits a periodic behaviour and, thus, it will be able to switch to an autonomous control mode that avoids the resolution of an optimisation problem online. The proposed control strategy is tested in a manufacturing process line in which changes in the production programs are considered with the aim to test the performance in flexible manufacturing scenarios. The obtained results show that the computational burden could be significantly reduced while reducing global energy consumption without affecting the system productivity., Peer Reviewed, Postprint (author's final draft)

The manufacturing industry is shifting towards smart manufacturing, in which both energy efficiency and flexibility are some of the main objectives of this digital transformation. In this regard, the control strategies for manufacturing systems should be able to support the requirements of this transformation with a low computational burden towards their implementation in real time. To this end, in this paper, a dual mode control strategy based on two control approaches is proposed to minimise the energy consumption of manufacturing systems without affecting their productivity, even when scenarios of flexible manufacturing are considered. The first control mode is based on model predictive control to determine an optimisation-based strategy for the constrained behaviour of the system. Then, the second mode builds on the assumption that the system exhibits a periodic behaviour and, thus, it will be able to switch to an autonomous control mode that avoids the resolution of an optimisation problem online. The proposed control strategy is tested in a manufacturing process line in which changes in the production programs are considered with the aim to test the performance in flexible manufacturing scenarios. The obtained results show that the computational burden could be significantly reduced while reducing global energy consumption without affecting the system productivity.

Gradu Amaierako Lan honetan zehar, JADE agenteak eta PLC bat komunikatzeko plataformaren diseinua garatzen da. Java-z programatutako agente bat automatarekin komunikatuko da, C++-z programatutako eta ODK izeneko erdikari bat erabiliz, etorkizunean plataforma hau manufaktura malguko sistema batean integratzeko. Proiektu honetan plataforma garatzeko beharrezkoak diren errekurtsoak eta erabiliko diren hardwarea eta softwarea garatzeko beharrezkoak diren programak azalduko dira., Along this Final Degree Project,the design of a communication platform between a JADE agent and a PLC is developed.A Java programmed agent is communicated with a PLC program using a middlewarecalled ODK,programmed in aC++ application, to, in anearfuture, be able to have this platform integrated in a flexible manufacturing system.In this project the resources needed to createthe platformare explained, as well as the hardware and the programs that are going to be used to develop the software., Gradu Amaierako Lan honetan zehar,JADE agenteak eta PLC bat komunikatzeko plataformaren diseinua garatzen da. Java-z programatutako agente bat automatarekin komunikatuko da, C++-z programatutako eta ODK izeneko erdikari bat erabiliz, etorkizunean plataforma hau manufaktura malguko sistemabatean integratzeko.Proiektu honetan plataforma garatzeko beharrezkoak diren errekurtsoak eta erabiliko diren hardwarea eta softwarea garatzeko beharrezkoakdiren programakazalduko dira.

En este trabajo fin de grado se desarrolla el control de un brazo robótico manipulador WidowX y su sensorización, todo ello montado sobre una plataforma TurtleBot 2. Este trabajo pretende integrar las funciones propias del brazo con las de una base móvil para ofrecer servicios de transporte y manipulación en un sistema de fabricación flexible. Para entender este conjunto se describen todos los equipos que lo componen. El control de todos estos dispositivos se realiza desde ROS (Robot Operating System) y se desarrolla la interacción de los equipos en este entorno., Throughout this document, the control of a WidowX robotic arm and its sensorization aredeveloped, mountedon top of a TurtleBot 2 structure. The aim of this project is to add the capabilities this robotic arm provides to a mobile base part of a flexible manufacturing system. Every piece of hardware isdescribed in order to grasp how everything interacts. The control of these devices is conducted using ROS (Robot Operating System). ROS’ working structure and how it manages the devices’ control are explained., Gradu amaierako lan honetan WidowX beso robotiko manipulatzailearen kontrolaeta honengainean zenbait sentsoreen kokapena garatzen dira,TurtleBot 2 robot mugikorraren gainean antolatua. Lan honek besoak ahalbidetzen dituen ekintzak ematen dizkio fabrikazio sistema malguko robot bati. Multzo hau osatzen duten gailu guztiak azaltzen dira. Gailu hauek kontrolatzeko ROS (Robot Operating System) erabiltzen da eta ingurune honetan nola komunikatzen direnazaltzen da.

This work gives a state-of-the-art overview regarding the scheduling of Automated Guided Vehicles (AGV) in Flexible (Re-)Manufacturing Systems (FMS/FRMS). Different, general approaches are available to solve this task. In this regard an overview of currently available fleet management software and research in this field as well as the simultaneous scheduling of machines and AGVs is given. Production scheduling and transport scheduling have been vastly studied by many researchers, but most of the works address these both problems separately. However, these two problems are closely linked and influence each other. By looking at them together, it is possible to achieve an improvement in the overall scheduling. The different works are examined regarding the consideration of one available machine for each tasks, or if alternative machines are available and if the approaches are static or dynamic. Especially the appropriability of the presented works regarding the use in remanufacturing systems is examined. Remanufacturing is a process for used products to make them “as good as new or better”. Due to unknown condition of the used products many challenges occur during the remanufacturing process which are special to the domain of remanufacturing and not know from manufacturing. The resulting stochastic routing of products and material in particular places special demands on the flexibility and dynamic of the scheduling and control of the remanufacturing system. In order to meet the challenges of a real remanufacturing system, the scheduling algorithm should consider alternative machines as well as be dynamic. None of the approaches examined can meet these requirements, which is why new methods have to be developed.

The growing need for smart and flexible systems in many areas of industry, such as manufacturing, smart grids,building automation systems and others, has resulted in new design approaches such as Cyber-physical systems (CPS). This raised the need for formal modelling of these systems to address reliability and robustness requirements. This paper addresses the problem of developing a formal semantics, based on abstract state machines (ASM), for modelling of distributed control systems for industrial CPS based on the IEC 61499 standard. The developed approach allows to build formal models of flexible distributed control systems for analysis and verification of various properties., ISBN för värdpublikation: 978-1-7281-0303-7

The design and operation of manufacturing systems is evolving to adapt to different challenges. One of the most important is the reconfiguration of the manufacturing process in response to context changes (e.g., faulty equipment or urgent orders, among others). In this sense, the Autonomous Transport Vehicle (ATV) plays a key role in building more flexible and decentralized manufacturing systems. Nowadays, robotic frameworks (RFs) are used for developing robotic systems such as ATVs, but they focus on the control of the robotic system itself. However, social abilities are required for performing intelligent interaction (peer-to-peer negotiation and decision-making) among the different and heterogeneous Cyber Physical Production Systems (such as machines, transport systems and other equipment present in the factory) to achieve manufacturing reconfiguration. This work contributes a generic multi-layer architecture that integrates a RF with a Multi-Agent System (MAS) to provide social abilities to ATVs. This architecture has been implemented on ROS and JADE, the most widespread RF and MAS framework, respectively. We believe this to be the first work that addresses the intelligent interaction of transportation systems for flexible manufacturing environments in a holistic form.

[EN] In order to develop the higher education system of Azerbaijan, training of highly skilled specialists using the innovative methods in teaching process and scientific research had been disscused at Sumgayit State University. The conceptual model of the process of preparation of highly qualified (multy) specialists was proposed on the basis of chairs in engineering and economics faculties of Sumgayit State University.Priority specialties and scientific directions of the departments of Engineering and Economics of Sumgayit State University were determined and the functional scheme of complex educational training - scientific research - production - commissioning system was proposed based on the principles of flexible production. An activity block diagram for the development of an innovative project in training, scientific research, production and commercial system has been developed.

Maximizing the benefits of time-of-use pricing for industrial electricity consumers requires varying production rates, such that energy use is shifted from peak price periods to off-peak times dining the day. Assuming that excess capacity and product storage arc available, production of energy intensive processes can be increased at off-peak times beyond nominal rates, and the stored product can be used at peak times when the production rate is lowered. Under these rapidly changing circumstances, scheduling calculations must take into consideration explicitly the dynamic model of the process, often rendering the scheduling problem intractable in practical amounts of time. To address this challenge, we introduce a class of scheduling-relevant low-order process models, which capture the closed-loop input-output behavior of a plant. We use these models to close the scheduling loop, whereby the scheduling problem is formulated over a moving horizon with feedback. We apply the theoretical concepts to an industrial-scale air separation unit model, demonstrating that variable production rate operation with product storage has the potential for significant operating cost savings while abiding by product quality and safety constraints., QC 20161017

This article presents a designed productive case which includes the virtual laboratories of the Universidad Tecnologica Pereira’s Industrial Faculty, it means the flexible manufacturing cell and the mobile logistics laboratory; this case was named “PR ATV’s production case”. It was structured in trying to imitate a real process of production of ATVs with their logistics process. There is described the form in which is designed the adaptations of existing resources within the manufacturing cell with the aim of to execute the process in the laboratory., El presente artículo explica el diseño de un caso productivo que vincula los laboratorios virtuales de la Facultad de Ingeniería Industrial de la Universidad Tecnológica de Pereira, es decir, la celda de manufactura flexible (FMC) y el laboratorio móvil de logística. El caso se denominó "Caso de producción Cuatrimotos PR". Lo estructuramos en detalle, procurando asemejarlo al proceso real de producción de cuatrimotos con su proceso logístico. Se describe la forma en que se diseñaron adaptaciones a los recursos existentes dentro de la celda de manufactura con el objetivo de ejecutar el proceso en el laboratorio.

In a truly flexible manufacturing system the description of the control strategy must be updated every day. Hence, a new way to handle changes in the environment down to control system deployment and production is required. This paper presents a novel approach, based on P-SOP, to handle multi-agent based control and verification. The P-SOP approach addresses flexibility, robustness and deployment in the best possible manner with the least waste of time and effort. P-SOP includes a description language where the control strategy based on actual circumstances easily can be defined. Based on the description multi-agents, to control the manufacturing, are automatically generated. An industrial advantage is that the multi-agent generator creates IEC 61131-3 PLC code that can be executed on standard PLC’s. This feature eliminates the need for experts in PLC programming and reduce deployment time to become more efficient. Hence, this flexibility enables small series down to one off production in a competitive way. With multi-agent control it is also possible to handle rebalancing due to market changes, scheduling of available humans, introduction of new part types, and rerouting due to a machine break down or planned service. The generated agents are not optimised for a final solution with specific timings. All decisions are made on-line and the generated solution adapts to the circumstances that arise. With the P-SOP multi-agents it is easy to manually remove or introduce parts to the manufacturing cell without disturbing the system, e.g. for manually random inspections, removal of parts due to restart. The formulated description language and the multi-agent generator has been successfully tested and evaluated in an industrial environment., Available online 7 February 2015

The regeneration process of jet engines is a highly complex, expensive and time-consuming. Especially the regeneration of high pressure turbine blades and compressor blisks are at the border of what is technically feasible. These components are highly loaded and thus substantial wear occurs. The blades and blisks must be overhauled or replaced regularly. The existing repair methods for these parts are inflexible and cannot be applied in many cases, resulting in a large number of scrapped parts. Therefore a new turbine blade regeneration process is presented. The goal of the improved process is to reduce the scrap rate and cost. This process includes an early evaluation of the condition of the hot-gas path components before disassembly, new detection methods for defects on the turbine blades surfaces, and more flexible manufacturing processes. The process is supported by production process simulations and functional simulations to predict the optimal regeneration path depending on the blade condition and the business model of the customer. The paper also presents a new approach for compressor blisk regeneration. This process will be developed and validated in the next years. New challenges in structural mechanics, aerodynamics, and manufacturing must be addressed due to the complexity of blisks. As part of the ongoing research, three new blisks will be designed and subjected to the complete regeneration path, which is also supported by simulations. In order to validate the simulations, their results will be compared to experimental results of the regenerated components on a compressor test rig.

Speed, precision and repeatability are virtues of industrial robots which are relied on by manufacturing firms but also necessitates segregating them within controlled fenced areas. Therefore, industrial robots cannot cooperate with line workers in assembling task. With recent developments in robotics, new possibilities have emerged that can enable manufacturing firms to be flexible and cost effective. This paper presents preliminary results from investigations into the possibility of a man-machine production cell where plastic panels are assembled under the car. A conceptual man-machine collaborative production cell will be presented detailing characteristics required to ensure safety., Collaborative Team of Man and Machine ToMM

This paper present a Part oriented Sequence of Operation (P-SOP) approach that address flexibility, robustness and deployment in manufacturing cells up to plant level. A P-SOP description language has been formulated where the control strategy based on actual circumstances easily can be defined. Furthermore, a P-SOP multi-agent generator has been created that compiles the strategy description to multi-agents that control the manufacturing. Deadlock free IEC 61131-3 PLC code are directly generated from the description language. The code is not optimised for a specific scenario since the general description contains all possible routing paths and all resources available.

The aim of this paper is to describe on-going work in the integration of humans in automated manufacturing systems. The intention is to achieve a flexible manufacturing system to meet the rapid developing and changing of today’s industry. The approach is based on a control concept with multi-agents. Humans, which are considered as a valuable factor in industrial production, are proposed as flexible agent resources for the automated manufacturing system. A test case was performed on a manufacturing system where three different groups of humans where integrated in the system; inspection, carrier and recovery. The P-SOP agent generator was used to automatically generate IEC 61131-3 PLC control code for the system.

In a flexible manufacturing industry the production planner may need to make an updated description of the control strategy every day. The description contains all possible routing paths and is based on actual circumstances. It varies depending on, e.g., rebalancing due to market changes, scheduling of available operators, introduction of new parts, and rerouting due to a machine break down or planned service. A Part oriented Sequence of Operation (P-SOP) description language has been formulated to assist the production planner to be able to handle these flexible manufacturing scenarios. Multi-agents to control the manufacturing are automatically generated from the P-SOP description language. The P-SOP agent generator creates IEC 61131-3 PLC code that can be executed on standard PLC’s. An agent consists of a head, a communicator and a body. The head and the communicator are the automatically generated part with a predefined interface against the physical body, e.g., the mechanical/electrical structure of a robot. This feature eliminates the need for an external expert in PLC programming. The head contains many small sub-sequences for all operations that are defined for the specific body. The purpose of the communicator is to communicate with surrounding neighbour agents to form a multi-agent system. The formulated language and the P-SOP agent generator has been successfully tested and evaluated in an industrial environment.

[EN] A flexible manufacturing system enables automatic production of a family of different pieces minimizing, and in some cases eliminating, the additional costs of manufacturing changes and therefore provides unitary costs and productivity reserved to large series manufacturing. In practice, many manufacturing systems use these technologies, under a technical and organizational perspective, and always adapted to a specific manufacturing task, trying to configure systems according to the market strategy of the company., [ES] La fabricación flexible es un sistema que permite la producción automática de una familia de piezas diferentes minimizando, y en algunos casos eliminando, los costes adicionales por el cambio de fabricación, y que proporciona por tanto una productividad y unos costes unitarios reservados hasta ahora a la fabricación de grandes series. En la práctica se utilizan bastantes sistemas de este tipo, bajo una concepción técnica y organizativa siempre adaptados a la tarea específica de fabricación, tratando de configurar sistemas acordes a la estrategia de mercado de la empresa.

The life-cycle extension of weapon systems has created problems for sustaining spare parts procurement. This study analyzes selected DOD reprocurement initiatives for securing responsive manufacturing capacity of small manufacturing companies to overcome these problems. Interviews were also conducted with Government and industry representatives and managers of small manufacturing shops to identify possible barriers to the application of the DOD initiatives. The findings reveal that the DOD initiatives and their associated technologies could dramatically reduce costly lead time delays by enabling the electronic exchange of technical product data between a geographically dispersed set of qualified machine shops and DOD supply centers. However, unless DOD efforts are directed at unifying the components necessary for procuring legacy weapon system spare parts, the barriers will remain as significant obstacles, http://archive.org/details/analysisofselect00fill, Lieutenant, United States Navy, Approved for public release; distribution is unlimited.

This study is based on a new approach for an advanced microproduction system or highly flexible production systems where all necessary production and assembly processes are connected in a very flexible way using autonomous mobile transport and handling robots. Each robot has to follow its planned paths while avoiding collisions with other robots. In addition, problem-specific constraints for a defined microproduction system, such as limitations of the velocity and accelerations of the robots, have to be fulfilled. This paper focuses on a two-level model predictive optimizing approach. On a global long-term level, simple dynamic models of the robots are used to compute optimal paths under differential constraints where a safety distance between all robots is achieved. Since many uncertainties and unforeseen events could occur, all robots also use a nonlinear model predictive control approach on a local real-time level. This control approach solves the path following and the collision avoidance problems in parallel, while also taking into account differential constraints of the single robots.

In this paper we address flexibility and investigate the relationship between volume and product mix flexibility. One view of flexibility is that of being a capability in itself: another view is that of flexibility as an enabler, providing the manufacturing system with properties on which other competitive capabilities are built. In this research, the latter view of flexibility is used, where flexibility acts as a second order competitive criterion. The aim is to differentiate between two dimensions of flexibility important to the manufacturing value chain, i.e., volume and product mix flexibility, and to investigate how different flexibility configurations are related to Various manufacturing practices. A clustering research approach is used to identify groups of companies based on flexibility configurations. The groups are then analyzed with respect to characteristics and impact on operational performance. For the empirical investigation, we use empirical data from the high performance manufacturing (HPM) study, including three industries and seven countries-a total of 211 plants. We find that flexibility configurations based on high or low levels of volume and mix flexibility combinations show significant differences both in terms of operational performance, and in terms of emphasis put into different flexibility source factors., Original Publication: Mattias Hallgren and Jan Olhager, Flexibility configurations: Empirical analysis of volume and product mix flexibility, 2009, OMEGA-INTERNATIONAL JOURNAL OF MANAGEMENT SCIENCE, (37), 4, 746-756. http://dx.doi.org/10.1016/j.omega.2008.07.004 Copyright: Elsevier Science B.V., Amsterdam. http://www.elsevier.com

This work was aimed at developing computational intelligence for scheduling a manufacturing cell’s tasks, based mainly on genetic algorithms. The manufacturing cell was modelled as being a production-line; the makespan was calculated by using heuristics adapted from several libraries for genetic algorithms computed in C++ builder. Several problems dealing with small, medium and large list of jobs and machinery were resolved. The results were compared with other heuristics. The approach developed here would seem to be promising for future research concerning scheduling manufacturing cell tasks involving mixed batches., El propósito del trabajo fue plantear una metodología para la programación de tareas de una celda de manufactura, basada principalmente en algoritmos genéticos. La celda de manufactura fue modelada como una línea de flujo, y se desarrollaron cálculos que permiten saber el makespan usando una heurística adaptada de una librería realizada para algoritmos genéticos, esto implantado en un ambiente de programación C++ builder. Se resolvieron problemas diversos, considerando distintos tamaños de lista en trabajos y máquinas, los cuales fueron comparados con los resultados de otras heurísticas. Los futuros trabajos pueden considerar la programación de tareas en celdas de manufactura con lotes de diferentes volúmenes.

This work was aimed for developing computational intelligence for scheduling a manufacturing cell's tasks, based manily on genetic algorithms. The manufacturing cell was modelled as beign a production-line; the makespan was calculated by using heuristics adapted from several libraries for genetic algorithms computed in C++ builder. Several problems dealing with small, medium and large list of jobs and machinery were resolved. The results were compared with other heuristics. The approach developed here would seem to be promising for future research concerning scheduling manufacturing cell tasks involving mixed batches., El propósito del trabajo fue plantear una metodología para la programación de tareas de una celda de manufactura, basada principalmente en algoritmos genéticos. La celda de manufactura fue modelada como una línea de flujo, y se desarrollaron cálculos que permiten saber el makespan usando una heurística adaptada de una librería realizada para algoritmos genéticos, esto implantado en un ambiente de programación C++ builder. Se resolvieron problemas diversos, considerando distintos tamaños de lista en trabajos y máquinas, los cuales fueron comparados con los resultados de otras heurísticas. Los futuros trabajos pueden considerar la programación de tareas en celdas de manufactura con lotes de diferentes volúmenes.

An algorithm is presented that is based on a representation method for products, which lets us show, intuitively, the hierarchical relationships among components and/or assemblies of the product. This paper presents an algorithm for establishing a partial non-destructive disassembly sequence of a product. The disassembly sequence can be obtained for a component as well as for a sub-assembly (group of different components). The disassembly sequence is obtained autonomously and automatically and can be used in a flexible manufacturing system.

The work detailed in this dissertation relates to thedevelopment of high performance manufacturing systems. Theperformance factor aimed for is especially flexibility, butthere is an intention of making the results adaptable to focuson performance factors of the readers or users choice. Thefocus of the presented research is not only to provide meansfor accomplishing manufacturing that can handle changes butalso to accomplish flexibility in another area. The resultsshould be applicable in many different situations. The researchhas been divided into three parts: the further development of amanufacturing strategy, the development of a base for amanufacturing system design method and the development of amanufacturing control system. The developed strategy is called Assembly-InitiatedProduction (AIP). An implementation of the strategy shouldprovide high manufacturing system flexibility but at the sametime contribute to the lowering of inventory levels andlead-times. Different solutions coupled to technicalrequirements found are also discussed. The design method research focuses on basic manufacturingsystem properties and the possibility of expressing theseproperties by using simple combinable abstract units calledconcepts. The principle is the same as in physics where realworld phenomena may be expressed by using standard concepts asfor example time and mass. The intended use of the results isin an early manufacturing system design phase. The method isnot directly linked to the AIP strategy, but could be used forimplementing it. Production Planning and Control (PPC) is an important partof a manufacturing system. After having reviewed current PPCpractices, a need for a factory floor PPC system workingregardless of factory floor layout, was identified. Based ontheoretical and industrial studies, the suggested solution is acomputerised, decentralised control system, physicallyseparated from the PPC/ERP system. In order to be able to makequick changes in the schedule, to obta, NR 20140805

This paper will serve as the documentation for the Tool Optimization codeof the HSE software. The purpose of the software is, simply, to enable auser to optimize a factory's tool selection. This will be added to theexisting Factory Administrator which enables users to understand theeffects of changes in many parts of the manufacturing process (i.e. Temperatures, Pressures, etc.).To accomplish this an interface was designed via the DELPHI programminglanguage that can take inputs from a user as well as factory details froman Excel spreadsheet, run simulations, determine an optimal toolconfiguration, and output this data as easily as possible to the user.The Interface will guide the Simulation as many times as needed to performits gradient analysis. After the program is complete, it determines a bestcase tool configuration that meets the user's throughput while maintainingto his budget. The interface will output how many of each tool to purchaseas well the best possible tool allocation (usage) for each tool.

We proposetwo finite difference two-timescale simultaneous perturbationstochastic approximation (SPSA)algorithmsfor simulation optimization ofhidden Markov models. Stability and convergence of both thealgorithms is proved.Numericalexperiments on a queueing model with high-dimensional parameter vectorsdemonstrate orders of magnitude faster convergence using thesealgorithms over related $(N+1)$-Simulation finite difference analoguesand another two-simulation finite difference algorithm that updates incycles.

This paper will serve as the documentation for the Tool Optimization codeof the HSE software. The purpose of the software is, simply, to enable auser to optimize a factory's tool selection. This will be added to theexisting Factory Administrator which enables users to understand theeffects of changes in many parts of the manufacturing process (i.e. Temperatures, Pressures, etc.).To accomplish this an interface was designed via the DELPHI programminglanguage that can take inputs from a user as well as factory details froman Excel spreadsheet, run simulations, determine an optimal toolconfiguration, and output this data as easily as possible to the user.The Interface will guide the Simulation as many times as needed to performits gradient analysis. After the program is complete, it determines a bestcase tool configuration that meets the user's throughput while maintainingto his budget. The interface will output how many of each tool to purchaseas well the best possible tool allocation (usage) for each tool.

Cluster tools are highly integrated machines that can perform a sequence of semiconductor manufacturing processes. The sequence of wafer handler moves affects the total time needed to process a set of wafers. Reducing this time can reduce cycle time, reduce tool utilization, and increase tool capacity. This paper introduces the cluster tool scheduling problem for hybrid cluster tools, which are multiple-stage tools that have at least one stage with two or more parallel chambers. This paper presents algorithms that can find superior sequences of wafer handler moves. Experimental results show that the tool performance can be improved significantly if the wafer handler follows a cyclic sequence instead of using a dispatching rule.

Cluster tools are highly integrated machines that can perform a sequence of semiconductor manufacturing processes. The sequence of wafer handler moves affects the total time needed to process a set of wafers. Reducing this time can reduce cycle time, reduce tool utilization, and increase tool capacity. This paper introduces the cluster tool scheduling problem for sequential cluster tools and describes a branch-and-bound algorithm that can find an optimal sequence of wafer handler moves. In addition, we enumerate the set of 1-unit cyclic sequences for two- and three-stage sequential cluster tools. Experimental results show that the tool performance can be improved significantly if the wafer handler follows a cyclic sequence instead of using a dispatching rule.

The objective of this effort was to improve manufacturing flexibility by developing a systematic approach to improving the product-process design methodology using transactions analysis and feature-base methods of computer system and database design for the automotive components and sheet metal operations. The first two-and-a-half sections of this report duplicate to a significant degree the report submitted by the sister project Fast and Flexible Communication of Engineering Information in the Aerospace Industry, because this work was executed in a nearly seamless fashion. The later sections of this report provide outputs distinct from those reported by the sister project, although many of the insights cannot be easily traced to one of the projects to the other exclusion.

One of the important activities in process planning is the design of fixtures to position, locate and secure the workpiece during operations such as machining, assembly and inspection. The proposed approach for variant fixture planning is an essential part of a hybrid process planning methodology.The aim is to retrieve, for a new product design, a useful fixture from a given set of existing designs and their fixtures. Thus, the variant approach exploits this existing knowledge. However, since calculating each fixture's feasibility and then determining the necessary modifications for infeasible fixtures would require too much effort, the approach searches quickly for the most promising fixtures based on a surrogate design similarity measure. Then, it evaluates the definitive usefulness metric for those promising fixtures and identifies the best one for the new design.

Optimal multilevel control policies for rate based flow control in available bit rate (ABR) service in asynchronous transfer mode (ATM) networks are obtained in the presence of information and propagation delays, using a numerically efficient two timescale simultaneous perturbation stochastic approximation (SPSA) algorithm. Numerical experiments demonstrate fast convergence even in the presence of significant delays and a large number of parametrized parameter levels.

Flexible manufacturing systems (FMSs) have been widely accepted by the modern manufacturing industries. However, in comparison with the capabilities of FMS hardware systems, the sophistication of software systems is still far away from the goal that we expected in order to realize optimum FMS control. The fact is that the rate of acceptance of FMSs actually far exceeds the rate of implementation of these expensive manufacturing systems. Therefore, the primary goal of this research is to advance software control capabilities of FMSs. To this end, the research has presented a new methodology as the framework for the development of FMS software control systems. First, to reduce the complexity of software development, the hierarchical control architecture exclusively used for FMS software control systems is designed and presented. Secondly, in order to systematically, precisely, and concisely represent the dynamic behaviors of FMS control, the research has introduced the Colored Petri Net (CPN) as the modeling tool and further developed a number of CPN models. In particular, the CPN models are developed for three FMS control levels: System, Workstation, and Device. Thirdly, an object-oriented design and development architecture, called FMS hierarchical foundation classes library (FMS/FCL), has been defined and further developed, which can significantly increase the reliability and reusability of FMS system control software. Finally, a graphic software verification prototype, called DDE Verifier, has also been developed in the research. It is believed that all these research efforts will make important contributions on the methodology of design and development of FMS software control systems.

One of the important activities in process planning is the design of fixtures to position, locate and secure the workpiece during operations such as machining, assembly and inspection. The proposed approach for variant fixture planning is an essential part of a hybrid process planning methodology.The aim is to retrieve, for a new product design, a useful fixture from a given set of existing designs and their fixtures. Thus, the variant approach exploits this existing knowledge. However, since calculating each fixture's feasibility and then determining the necessary modifications for infeasible fixtures would require too much effort, the approach searches quickly for the most promising fixtures based on a surrogate design similarity measure. Then, it evaluates the definitive usefulness metric for those promising fixtures and identifies the best one for the new design.

The Black & Decker factory in Easton, Maryland, uses parallel, off-line assembly lines to produce multiple models in small, infrequent production runs. The University of Maryland and Black & Decker have implemented an Internet-based work instructions system that supports parallel, off-line assembly. Black & Decker personnel create and update easy-to-read paperless work instructions, and each assembly station automatically retrieves the correct paperless work instructions and displays them.

In the absence of a major new threat, the national security of the United States will have to be guaranteed with a significantly smaller defense budget. For better or for worse, efficiency now shares top billing with effectiveness because in the new order, cost have become the biggest enemy for any weapon system. This article addresses ways by which the logistical support of the war fighter can be provided much more efficiently than ever before, without materially sacrificing effectiveness., Published in Airpower Journal, p81-92, Summer 1997.

Mass Customization aims at producing customized products to meet individual customer's needs with mass production efficiency. The advent of this new mode of manufacturing introduces a different set of requirements on system control for manufacturing operations. The implications include the drastic increase of varieties, very small batch size, random arrival of orders, and wide spread of due dates. In addition, there are also factors such as similarity among tools, production plans and product designs. If properly utilized, that can help to reduce the complexities of the control systems. In order to develop a new type of control and coordination system to support mass customization, a heterogeneous coordination mechanism is developed. A price mechanism with the construct of intelligent agents in a market-like environment is investigated to fulfill the requirements.

This paper presents the implementation of a client/server control system for a manual Flexible Assembly System (FAS) with automatic material handling. The system is designed for mass customisation manufacturing in which products are made to customer orders in small batches or one-of-a-kind production with mass production efficiency. This paper presents the control framework for the lower level of hardware control and the integration of an automatic storage/retrieval system (AS/RS) with the FAS. In addition, the system allows product customisation through Internet and its implementation will be discussed. A prototype system for customisation and production of a family of desk clocks will be described.

Building a reliability is fundamentally difficult because detailed mechanistic origins of reliability failures are not commonly known. Controlled process experiments and sophisticated characterization methods offer hope of revealing mechanisms more broadly. Real-time and in-line sensors present perhaps even more potential in two cases, (1) when their information is correlated with reliability performance, and (2) when used to achieve process control through course correction and/or fault management; the later has special value in difficult situations where the reliability failure emerges from process integration sensitivities. Integrated modeling and simulation structures provide a vehicle for broad knowledge capture, and enabler of design optimization from reliability and other metrics, and a platform for effective process control.