No description available.

<p>Textiles have gained popularity in wearable products due to their potential for wearability, comfort, flexibility, breathability, and seamless fit to the human body. The growing demand for remote telehealth monitoring has led to advancements in the field of e-textiles. Various approaches, such as dip coating, screen printing, inkjet printing, and vapor deposition, are utilized to overcoat fabrics with active nanomaterials. However, practical deployment still faces challenges due to a lack of rapid prototyping for scalable and customizable e-textiles. To meet the requirements of large-scale batch production, high-resolution electrode line width, and long-term durability, new platform technologies have been established to convert existing textiles into multifunctional e-textiles. These studies have also revealed the process-structure-property relationships of various e-textiles.</p> <p>Chapter I overviews the recent results and current limitations of e-textiles in wearable sensing and display. Since people stay and work in various circumstances, continuous monitoring of physical, electrophysiological signals on skin in ambulatory manners is necessary to evaluate hazardous situation or chronicle symptoms. For these reasons, fabrication of smart e-textiles is crucial. In this chapter, various conductive materials, overcoating methods, and sensor structures for physical and electrophysiological sensors are reviewed. In addition, as a useful user communication tool with different sensor system, e-textile formats of displays are developed. The comprehensive e-textile displays from DC-driven to AC-driven are presented.</p> <p>Chapter II introduces a dual-regime spray technique that enables the direct writing of functional nanoparticles onto commercial 4-way stretchable textiles up to a meter scale with high-resolution mask-free patterning. The resulting e-textiles maintain the intrinsic properties of the fabric and can conform to various body shapes, enabling high-fidelity recording of physiological and electrophysiological signals under ambulatory conditions. Field tests have shown the potential of these e-textiles for minimally obtrusive remote telehealth monitoring of large animals.</p> <p>Chapter III presents an in-situ polymerization and patterning technique that utilizes the dual-regime spray method to synthesize conductive polymers directly onto commercial stretch textiles. The resulting e-textiles are utilized for strain sensors that conform closely to the human body, providing exceptional measurement accuracy and fidelity in capturing physical signals and motion detections.</p> <p>Conclusion section summarizes this dissertation with pointing out important results and discussions of each study. As an innovative additive manufacturing technology, dual-regime spray system, was established and developed to open new field in manufacture of e-textile. At last of this section, the potential research opportunities and perspectives are addressed. </p>

<p>Passive chipless wireless sensors have gained great attention in Radio Frequency Identification (RFID) applications, inventory tracking, and structural health monitoring, as they offer a prospective low-cost, scalable alternative to the state-of-the-art active sensors. While the popularity and demand for chipless sensors are on the rise, their applications are limited to low-noise environments and their caliber as low-cost, scalable devices has not been explored to a successful degree in challenging domains, such as precision agriculture, healthcare, and food packaging. Size, cost of materials, and complexity of the manufacturing process are the main obstacles to progress in the large-scale production of chipless sensors for practical applications. </p> <p><br></p> <p>Conventional manufacturing processes, such as photolithography, are costly, cumbersome, and time intensive. While additive manufacturing techniques, such as printing technologies, have circumvented some of these challenges, printing techniques require costly inks and complex post-processing steps, such as drying and sintering, which limit their large-scale utilization. To overcome these challenges, this dissertation focuses on investigating the possibility of utilizing laser processing of conventional metalized films and polymers to develop cost-effective chipless sensors. This Scalable Laser Assisted Manufacturing (SLAM) process offers a platform for large-scale roll-to-roll production of high-resolution sensors for precision agriculture, healthcare, and food packaging applications. </p> <p><br></p> <p>In this pursuit, the first study explores combining the SLAM process with 3D printing to develop a miniaturized, biodegradable, chipless sensor for soil moisture monitoring. In the second study, the SLAM process is further explored in the development of metalized stickers for healthcare applications focusing on urine bag management and early risk detection of urinary tract infections. In the third study, the capability of the SLAM process to form moisture-sensitive metal nanoparticles as a co-product of metal patterning is harnessed to develop a chipless humidity sensor. The SLAM process is further expanded in the fourth study by functionalizing metalized films with stimuli-responsive polymers to achieve specificity in detecting unique biomarkers of food spoilage. The SLAM platform described in this work opens up new avenues toward processing metalized fabric for the future of wearable electronics and implementing multi-functional sensors for precision agriculture.</p> <p>  </p>

<p>Developed countries have built wealth and prosperity on the strength of their manufacturing sectors, with China’s success story of lifting 800 million people out of extreme poverty in 30 years a sterling and most recent example of how manufacturing-led industrialization can foster economic development. Sub-Saharan Africa, unfortunately, find itself today in a similar situation as China did in 1990, with over 50% of the world’s desperately poor 719 million people living in the region. But unlike China, Sub-Saharan Africa is faced with the additional challenge of overcoming poverty in a world with stricter constraints to global trade and climate change limitations to modern-day industrialization. Compounding the challenges further is the region's limited know-how and human capital — a consequence of years of underdevelopment, creating a classic chicken and egg dilemma where the lack of industrialization perpetuates the dearth of know-how and human capital, and vice versa.</p><p>Considering these challenges, we investigate how chemical manufacturing and what chemical manufacturing approaches can be leveraged to effectively drive industrialization and economic development in Sub-Saharan Africa. We propose chemicals manufacturing using prefabricated modules – which are constructed offsite in places with available human capital and transported to be assembled in places where they are needed – as a flexible and needed approach. However, Economy of Scale, which generally favors large-scale chemical manufacturing, poses as a major constraint to such modularization approach, especially given the presently small serviceable market sizes in Sub-Saharan Africa due to low purchasing power parity. We thus utilize mathematical modeling techniques to determine and establish scenarios for economic viability of the proposed approach, providing modeling frameworks and introducing measures for further studies in the process. We also provide and analyze exemplary flowsheets synthesized for a net-zero carbon emissions chemical manufacturing paradigm in the region.</p><p>This work concludes with a prefeasibility study of a chemical manufacturing project in Nigeria, as part of the author’s quest to build prefabricated modular plants across Africa. <i>Modular plants are attractive as they can be tuned to market demand of a developing market and region that needs them, putting less capital at risk.</i></p><p>This thesis is intended to be a vanguard of potential solutions to the complex challenges to industrialization in Sub-Saharan Africa. It endeavors to pave the way for addressing these issues through chemical manufacturing, offering valuable insights for sustainable progress.</p>

Especialmente nas últimas quatro décadas, muitos estudos se voltaram às variáveis determinantes para a implementação efetiva de sistemas flexíveis de manufatura, tais como seu design, sequenciamento e controle. Neste ínterim, o manejo apropriado do conjunto de ferramentas necessárias para a fabricação de um respectivo lote de produtos foi destacado como fator crucial no desempenho do sistema de produção como um todo. Neste trabalho, abordamos a otimização do número de inserções e remoções de ferramentas no magazine de uma ou mais máquinas numericamente controladas, admitindo-se que uma parcela significativa do tempo de produção é dispensada com estas trocas de ferramentas. De forma mais precisa, a minimização do número de trocas de ferramentas consiste em determinar a ordem de processamento de um conjunto de tarefas, bem como o carregamento ótimo do(s) compartimento(s) de ferramentas da(s) máquina(s), a fim de que o número de trocas seja minimizado. Como demostrado na literatura, mesmo o caso restrito à existência de apenas uma máquina de manufatura (MTSP, do inglês Minimization of Tool Switches Problem) é um problema NP-difícil, o que pode justificar o fato observado de que a maioria dos métodos de solução existentes o abordam de maneira heurística. Consequentemente, concluímos que a extensão ao contexto de múltiplas máquinas é também um problema NP-difícil, intrinsecamente complicado de se resolver. Nosso objetivo consiste em estudar formas eficientes de otimizar o número de trocas de ferramentas em ambientes equipados com máquinas flexíveis de manufatura. Para tanto, abordamos o problema básico, MTSP, e duas de suas variantes, em níveis crescentes de abrangência, que consideram o sequenciamento de tarefas em um conjunto de: (i) máquinas paralelas e idênticas (IPMTC, do inglês Identical Parallel Machines problem with Tooling Constraints); e (ii) máquinas paralelas e idênticas inseridas em um ambiente do tipo job shop (JSSPTC, do inglês Job Shop Scheduling Problem with Tooling Constraints). Classificamos as principais contribuições desta tese com respeito a três aspectos. Primeiramente, empurramos as fronteiras da literatura do MTSP propondo formulações matemáticas para os problemas IPMTC e JSSPTC. Desenvolvemos, também, algoritmos baseados em diferentes técnicas de resolução, como redução de domínio, Path relinking, Adaptive large neighborhood search e a elaboração de regras de despacho. Por último, com o intuito de bem avaliar a eficiência e o alcance de nossos métodos, propomos três novos conjuntos de instâncias teste. Acreditamos, assim, que este trabalho contribui positivamente com pesquisas futuras em um cenário abrangente dentro da minimização das trocas de ferramentas em um sistema flexível de manufatura. / Several studies, especially in the last four decades, have focused on decisive elements for the effective implementation of flexible manufacturing systems, such as their design, scheduling and control. In the meantime, the appropriate management of the set of tools needed to manufacture a certain lot of products has been highlighted as a crucial factor in the performance of the production system as a whole. This work deals with the optimization of the number of insertions and removals from the magazine of one or more numerical controlled machines, assuming that a significant part of the production time is wasted with such tool switches. More precisely, the minimization of tool switches problem (MTSP) consists on determining the processing order of a set of jobs, as well as the optimal loading of the magazine(s) of the machine(s), so that the total number of switches is minimized. As formally demonstrated in the literature, the MTSP is a NP-hard problem even when considering the existence of only one manufacturing machine, which could justify the fact that most of the solution methods tackles it heuristically. We thus conclude that its extension to the case of multiples machines is also NP-hard and, therefore, a problem intrinsically difficult to solve. Our goal consists in studying efficient ways to optimize the number of tool switches in environments equipped with flexible manufacturing machines. For that, we address the basic problem, MTSP, and two MTSP variants, in increasing levels of reach, that consider the job sequencing in a set of: (i) identical parallel machines (Identical Parallel Machines problem with Tooling Constraints, IPMTC); and (ii) identical parallel machines inserted in a job shop environment (Job Shop Scheduling Problem with Tooling Constraints, JSSPTC). The main contributions of this thesis are classified according three aspects. First, we pushed the frontier of the MTSP literature by proposing mathematical formulations for IPMTC and JSSPTC. We also developed algorithms based on different solution techniques, such as domain reduction, Path Relinking, Adaptive Large Neighborhood Search and dispatching rules. Finally, to fully evaluate the effectiveness and limits of our methods, three new sets of benchmark instances were generated. We believe that this work contributes positively to the future of research in a broad scenario inside the minimization of tool switches in flexible manufacturing systems.

Made available in DSpace on 2016-06-02T19:05:47Z (GMT). No. of bitstreams: 1 3340.pdf: 982188 bytes, checksum: 49ba39146aa7542a1670dd3d90507739 (MD5) Previous issue date: 2010-06-28 / Financiadora de Estudos e Projetos / In the context of automated manufacturing systems, combinatorial optimization problems, such as determining the production schedule, have been focused in many studies due to the high degree of complexity to their resolution. Several studies point to use of metaheuristics for the problem dealt, where different approaches perspectives have been proposed in order to find good solutions in a short time. In this paper, we propose an approach based on Ant Colony Optimization metaheuristic (ACO) for the reactive production scheduling problem in an FMS aiming the combination of problem characteristics with metaheuristic characteristics. For this, the problem is addressed from two perspectives, based on modeling and the search method. The problem representation is characterized by a description of the problem at the operations level, since the production schedule is included in this context. On the model is applied a constructive search method based on ACO that using the collaboration principle, establishing a relationship between operations so that it lead the search for promising regions of the solution space. The goal of this work is to obtain a reactive programming in acceptable response time in order to minimize the makespan values. Experimental results showed an improvement of the results obtained so far by other approaches. / No contexto de Sistemas Automatizados de Manufatura, problemas de otimização combinatória, como determinar a programação da produção, têm sido foco de estudo em muitas pesquisas devido ao alto grau de complexidade para sua resolução. Diversos trabalhos apontam para o uso de metaheurísticas para o tratamento do problema, onde diferentes perspectivas de abordagens têm sido propostas visando encontrar soluções de qualidade em um curto espaço de tempo. Neste trabalho, é proposta uma abordagem baseada na metaheurística Otimização por Colônia de Formigas (Ant Colony Optimization ACO) para o problema de programação reativa da produção em um FMS, com o objetivo de conciliar as características do problema com as características da metaheurística. Para isso, o problema é tratado em duas perspectivas, com base na modelagem e no método de busca. A modelagem do problema é caracterizada por uma descrição do problema em nível de operações, uma vez que a programação da produção está incluída neste contexto. Sobre o modelo é aplicado um método de busca construtiva baseado em ACO que usando o princípio de colaboração, estabelece uma relação entre as operações de forma que esta direcione a busca para regiões promissoras do espaço de soluções. O Objetivo deste trabalho é obter uma programação reativa em tempo de resposta aceitável, visando minimizar o valor de makespan. Resultados experimentais mostraram uma melhoria dos resultados até então obtidos por outras abordagens.

Made available in DSpace on 2016-06-02T19:05:50Z (GMT). No. of bitstreams: 1 3678.pdf: 5394148 bytes, checksum: 4abd3e7ce4acac9d5890eae3620c06d3 (MD5) Previous issue date: 2011-06-14 / Financiadora de Estudos e Projetos / In recent years, most companies apply techniques of industrial automation with the goal of increasing its efficiency. Increasingly Automated Guided Vehicles (AGVs) are used to transport work in factories and warehouses. The management of these AGV is the key to an efficient transport system. One of the main problems encountered in the management of AGV is the dispatching decision. This work proposes a method of dispatching of AGV with the ability to optimize the performance of flexible manufacturing systems (FMS) in real time. In the dispatching deciding can be chosen to optimize two objectives: makespan or tardiness. When the goal is to optimize the makespan are evaluated variables: distance, number of nodes, the input buffer and output buffer of the workstation. When the goal is to optimize the tardiness are evaluated variables: distance, number of nodes, task chaining, date of delivery. In both cases are also considered the time of the AGVs and the processing times of the workstations, so you can anticipate some decision-making. To perform the tests we used the softwares: Matlab, CPNtools and Automod, which allow simulations of how the method works dispatching AGVs before the method is implemented in factories. Based on the tests, we analyzed the improvement in makespan and tardiness compared to other studies, but also the flexibility of the method in which it is possible to exchange goals in operating time. / Nos últimos anos, mais empresas aplicam técnicas de automação industrial com o objetivo de aumentar sua eficiência. Cada vez mais Veículos Auto Guiados (AGVs) são usados para tarefa de transporte em indústrias e armazéns. O gerenciamento desses AGVs é a chave para um sistema de transporte eficiente. Um dos principais problemas encontrados no gerenciamento dos AGVs é a decisão de despacho. Esse trabalho propõe um método de despacho de AGV com capacidade de otimizar o desempenho de Sistemas Flexíveis de Manufatura (FMS) em tempo real. Na tomada de decisão do despacho podem ser escolhidos dois objetivos para otimização: makespan ou tardiness. Quando o objetivo é otimizar o makespan são avaliadas as variáveis: distância, número de nós, buffer de entrada e buffer de saída das estações de trabalho. Quando o objetivo é otimizar o tardiness são avaliadas as variáveis: distância, número de nós, encadeamento de tarefas, data de entrega do produto. Em ambos os casos também são considerados os tempos dos AGVs e os tempos de processamento das estações de trabalho, para que seja possível adiantar algumas tomadas de decisões. Para realizar os testes foram usados os softwares MatLab, CPNtools e Automod, os quais permitem que simulações do funcionamento do método de despacho de AGVs antes que o método seja implementado em fábricas. Com base nos testes realizados, analisou-se as melhoras no makespan e tardiness em comparação com outros trabalhos, como também a flexibilidade do método no qual é possível a troca de objetivos em tempo de operação.

因應物聯網、機器人和雲端計算等系統快速的科技創新，我們需要更有效之方法來模型化由上述系統所架構出來愈趨複雜的動態資源配置系統，以解決類似瓶頸、死結等潛藏的系統控制相關問題。為了解決以派翠網路模型化大型系統一直存在的指數倍數成長之複雜性問題，一個即使運用MIP（混合整數規劃）方法於可達性分析也是完全NP（非確定性多項式時間）的問題，趙玉教授率先以開發k階和k網系統的控制相關狀態(CRSs)數量之封閉形式解決方案(簡稱封閉解)，來突破此一指數倍數成長複雜性的障礙。然而，對稱網路結構的屬性，限縮了此兩系統在模型化系統中可應用的範圍;同時由於不可避免的死結的狀況，也阻礙了兩個系統的並行處理能力。為了延伸派翠網路封閉解的研究領域至非對稱系統，及強化對大型即時動態資源分配非對稱系統的模型化能力，本論文擴展派翠網路封閉解的研究領域至所謂的「左邊一般化k階系統」、「左邊一般化k網系統」和「A網系統」等三種不同類型的基本非對稱系統。「左邊一般化k階（相對於k網）系統」是在k階（相對於k網）之控製行程的任意位置，使用一非共享資源的網路模型，為模型化具有客製化製程系統之基本網路架構; 「A網系統」是在一k階系統中，連接一頂層非共享圈子網（TNCS）的網路模型，在實際應用中，為模型化具共享相同製程系統的基本網路架構。本論文透過非共用資源在等價網路(k階（相對於k網）)的影響性分析，及其等價網路之封閉解為基礎，建構「左邊一般化k階（相對於k網）系統」之封閉解;在「A網系統」中，由於TNCS和連接的缺陷 k階系統兩個子系統的獨立性，首先我們可以從其相關之k階系統的封閉解中，排除不可能狀態的數量，推導出缺陷k階系統的封閉解，然後以累計加總缺陷k階系統及TNCS兩個子系統在各種TNCS中存在不同權杖個數狀況下的封閉解乘積，構建出「A網系統」的封閉解。在實際應用中，我們可透過由封閉解所產生之即時CRS信息，強化對大型動態即時資源分配系統的模型化能力。例如，採用本論文所提出的避免死結演算法，可以在不用附加控制器之狀況下，實現k階和k網系統之並行處理的功能;並且可以在k-網系統中，在不用暫停所有系統的工作流程狀況下，實現動態行程配置的功能。除了應用虹吸計算方法構建非對稱系統的基礎封閉解外，本論文還提出了依據其反向網路被驗證的有效信息為基準，新的由模型驗證之以知識基礎的理論分析方法，加速派翠網路封閉解的建構。在此，本論文開啟了以變型k階系統為啟端，建構派翠網路封閉解新的研究時代。 / In the light of the rapid innovation of the Internet of Things (IoT), robot systems, and cloud computing systems, we need an efficient methodology to model gradually more and more complicated, real-time resource allocation systems (RAS), constructed using the systems mentioned above, for solving issues such as bottlenecks, deadlocks, and other embedded system-control-related problems. To solve the exponentially increasing complexity in the persistent problem of modeling large systems using Petri nets, which is an NP (nondeterministic polynomial time)-complete problem even when MIP (mixed integer programming) is employed for reachability analysis, Chao broke this barrier by developing the first closed-form solution (CFS) for the number of Control Related States (CRSs) for k-th order and k-net systems. However, the properties of symmetric net structures limit their application range in modeling systems; the inevitable deadlock obstructs the capability of concurrent processing in both systems. To enhance the capability of modeling large dynamic, real-time resource allocation in asymmetric systems, this dissertation extends the research on the CFS of PNs to the so-called Gen-Left k-th order system, the Gen-Left k-net system, and the A-net system, which comprise the three different types of fundamental asymmetric systems. A Gen-Left k-th order (resp. k-net) system is a k-th order (resp. k-net) system containing a non-sharing resource (NSR) at arbitrary locations in the control process, which is the fundamental net structure for modeling contained customized manufacturing processes inside a system. An A-net system is a k-th order system connected to a Top Non-sharing Circle Subnet (TNCS), which is the fundamental net structure to model a shared common manufacturing processing system in real applications. Based upon analyzing the effects of one NSR in the equivalent, the corresponding k-th order (resp. k-net) system, and an equivalent CFS, this dissertation derives the CFS for the Gen-Left k-th order (resp. k-net) system. Due to the independence of the TNCS and the connected Deficient k-th order system, we can first derive the CFS for a Deficient k-th order system just by excluding the number of impossible states from the CFS for its corresponding k-th order system. Then, the CFS of an A-net is constructed by summing the products of the CFS for the two sub-systems in each different case under the condition of the number of tokens inside TNCS. Based on real-time CRS information derived, we can enhance the capability for modeling a large dynamic, real-time resource allocation system in real applications. Employing the proposed deadlock-avoidance algorithm, for instance, we can realize concurrent processing in both k-th order and k-net systems without additional controllers being implemented; and the function of dynamic process allocation in a k-net system without suspending the system’s working flows. In addition to applying siphon computation to construct the fundamental CFS for asymmetric systems, this dissertation pioneers and proposes a new knowledge-based, analysis methodology, called proof by model, to accelerate the construction of the CFS for a PN based upon the validation information from its reverse net. This dissertation opens a new research era for constructing the CFS for PNs beginning from the Variant k-th order system.

Especialmente nas últimas quatro décadas, muitos estudos se voltaram às variáveis determinantes para a implementação efetiva de sistemas flexíveis de manufatura, tais como seu design, sequenciamento e controle. Neste ínterim, o manejo apropriado do conjunto de ferramentas necessárias para a fabricação de um respectivo lote de produtos foi destacado como fator crucial no desempenho do sistema de produção como um todo. Neste trabalho, abordamos a otimização do número de inserções e remoções de ferramentas no magazine de uma ou mais máquinas numericamente controladas, admitindo-se que uma parcela significativa do tempo de produção é dispensada com estas trocas de ferramentas. De forma mais precisa, a minimização do número de trocas de ferramentas consiste em determinar a ordem de processamento de um conjunto de tarefas, bem como o carregamento ótimo do(s) compartimento(s) de ferramentas da(s) máquina(s), a fim de que o número de trocas seja minimizado. Como demostrado na literatura, mesmo o caso restrito à existência de apenas uma máquina de manufatura (MTSP, do inglês Minimization of Tool Switches Problem) é um problema NP-difícil, o que pode justificar o fato observado de que a maioria dos métodos de solução existentes o abordam de maneira heurística. Consequentemente, concluímos que a extensão ao contexto de múltiplas máquinas é também um problema NP-difícil, intrinsecamente complicado de se resolver. Nosso objetivo consiste em estudar formas eficientes de otimizar o número de trocas de ferramentas em ambientes equipados com máquinas flexíveis de manufatura. Para tanto, abordamos o problema básico, MTSP, e duas de suas variantes, em níveis crescentes de abrangência, que consideram o sequenciamento de tarefas em um conjunto de: (i) máquinas paralelas e idênticas (IPMTC, do inglês Identical Parallel Machines problem with Tooling Constraints); e (ii) máquinas paralelas e idênticas inseridas em um ambiente do tipo job shop (JSSPTC, do inglês Job Shop Scheduling Problem with Tooling Constraints). Classificamos as principais contribuições desta tese com respeito a três aspectos. Primeiramente, empurramos as fronteiras da literatura do MTSP propondo formulações matemáticas para os problemas IPMTC e JSSPTC. Desenvolvemos, também, algoritmos baseados em diferentes técnicas de resolução, como redução de domínio, Path relinking, Adaptive large neighborhood search e a elaboração de regras de despacho. Por último, com o intuito de bem avaliar a eficiência e o alcance de nossos métodos, propomos três novos conjuntos de instâncias teste. Acreditamos, assim, que este trabalho contribui positivamente com pesquisas futuras em um cenário abrangente dentro da minimização das trocas de ferramentas em um sistema flexível de manufatura. / Several studies, especially in the last four decades, have focused on decisive elements for the effective implementation of flexible manufacturing systems, such as their design, scheduling and control. In the meantime, the appropriate management of the set of tools needed to manufacture a certain lot of products has been highlighted as a crucial factor in the performance of the production system as a whole. This work deals with the optimization of the number of insertions and removals from the magazine of one or more numerical controlled machines, assuming that a significant part of the production time is wasted with such tool switches. More precisely, the minimization of tool switches problem (MTSP) consists on determining the processing order of a set of jobs, as well as the optimal loading of the magazine(s) of the machine(s), so that the total number of switches is minimized. As formally demonstrated in the literature, the MTSP is a NP-hard problem even when considering the existence of only one manufacturing machine, which could justify the fact that most of the solution methods tackles it heuristically. We thus conclude that its extension to the case of multiples machines is also NP-hard and, therefore, a problem intrinsically difficult to solve. Our goal consists in studying efficient ways to optimize the number of tool switches in environments equipped with flexible manufacturing machines. For that, we address the basic problem, MTSP, and two MTSP variants, in increasing levels of reach, that consider the job sequencing in a set of: (i) identical parallel machines (Identical Parallel Machines problem with Tooling Constraints, IPMTC); and (ii) identical parallel machines inserted in a job shop environment (Job Shop Scheduling Problem with Tooling Constraints, JSSPTC). The main contributions of this thesis are classified according three aspects. First, we pushed the frontier of the MTSP literature by proposing mathematical formulations for IPMTC and JSSPTC. We also developed algorithms based on different solution techniques, such as domain reduction, Path Relinking, Adaptive Large Neighborhood Search and dispatching rules. Finally, to fully evaluate the effectiveness and limits of our methods, three new sets of benchmark instances were generated. We believe that this work contributes positively to the future of research in a broad scenario inside the minimization of tool switches in flexible manufacturing systems.

Cette thèse porte sur la navigation d'agents dans un environnement manufacturier. Le cadre général du travail relève de la navigation d'AGVs (véhicules autoguidés), transportant librement et intelligemment leur produit. L'objectif est de proposer des outils permettant la navigation autonome et coopérative d’une flotte d’AGVs dans des systèmes de production manufacturiers où les contraintes temporelles sont importantes. Après la présentation d'un état de l'art sur chaque domaine (systèmes manufacturiers et navigation d'agents), les impacts de la mutualisation entre ceux-ci sont présentés. Ensuite, deux problématiques, liées à la navigation d'agents mobiles dans des environnements manufacturiers, sont étudiées. La première problématique est centrée sur la planification de trajectoire décentralisée où une fonction d'ordonnancement est combinée au planificateur pour chaque agent. Cette fonction permet de choisir une ressource lors de la navigation afin d'achever l'opération du produit transporté le plus tôt possible. La première solution consiste en une architecture hétérarchique où les AGVs doivent planifier (ou mettre à jour) leur trajectoire, ordonnancer leur produit pour l'opération en cours et résoudre leurs propres conflits avec les agents à portée de communication. Pour la seconde approche, une architecture hybride à l'aide d'un superviseur, permettant d'assister les agents durant leur navigation, est proposée. L'algorithme de planification de trajectoire se fait en deux étapes. La première étape utilise des informations globales fournies par le superviseur pour anticiper les collisions. La seconde étape, plus locale, utilise les données par rapport aux AGVs à portée de communication afin d'assurer l'évitement de collisions. Afin de réduire les temps de calcul des trajectoires, une optimisation par essaims particulaires est introduite. La seconde problématique se focalise sur la commande coopérative permettant un rendez-vous d'agents non holonomes à une configuration spécifique. Ce rendez-vous doit être atteint en un temps donné par un cahier des charges, fourni par le haut-niveau de contrôle. Pour résoudre ce problème de rendez-vous, nous proposons une loi de commande à temps fixe (i.e. indépendant des conditions initiales) par commutation permettant de faire converger l’état des AGVs vers une resource. Des résultats numériques et expérimentaux sont fournis afin de montrer la faisabilité des solutions proposées. / This thesis is focused on agent navigation in a manufacturing environment. The proposed framework deals with the navigation of AGVs (Automated Guided Vehicles), which freely and smartly transport their product. The objective is to propose some tools allowing the autonomous and cooperative navigation of AGV fleets in manufacturing systems for which temporal constraints are important. After presenting the state of the art of each field (manufacturing systems and agent navigation), the impacts of the cross-fertilization between these two fields are presented. Then, two issues, related to the navigation of mobile agents in manufacturing systems, are studied. The first issue focuses on decentralized motion planning where a scheduling function is combined with the planner for each agent. This function allows choosing a resource during the navigation to complete the ongoing operation of the transported product at the soonest date. The first proposed approach consists in a heterarchical architecture where the AGVs have to plan (or update) their trajectory, schedule their product and solve their own conflict with communicating agents. For the second approach, hybrid architecture with a supervisor, which assists agents during the navigation, is proposed. The motion planning scheme is divided into two steps. The first step uses global information provided by the supervisor to anticipate the future collisions. The second step is local and uses information from communicating agents to ensure the collision avoidance. In order to reduce the computational times, a particle swarm optimization is introduced. The second issue is focused on the cooperative control, allowing a rendezvous of nonholomic agents at a specific configuration. This rendezvous must be achieved in a prescribed time, provided by the higher level of control. To solve this rendezvous, a fixed time (i.e. independent of initial conditions) switching control law is proposed, allowing the convergence of agent states towards a resource configuration. Some numerical and experimental results are provided to show the feasibility of the proposed methods.