Globally distributed additive manufacturing is a relatively new frontier in the field of product lifecycle management. Designers are independent of additive manufacturing services, often thousands of miles apart. Manufacturing data must be transmitted electronically from designer to manufacturer to realize the benefits of such a system. Unalterable blockchain legers can record transactions between customers, designers, and manufacturers allowing each to trust the other two without needing to be familiar with each other. Although trust can be established, malicious printers or customers still have the incentive to produce unauthorized or pirated parts. To prevent this, machine instructions are encrypted and electronically transmitted to the printing service, where an authorized printer decrypts the data and prints an approved number of parts or products. The encrypted data may include G-Code machine instructions which contain every motion of every motor on a 3D printer. Once these instructions are decrypted, motor drivers send control signals along wires to the printer's stepper motors. The transmission along these wires is no longer encrypted. If the signals along the wires are read, the motion of the motor can be analyzed, and G-Code can be reverse engineered. This thesis demonstrates such a threat through a simulated attack on a G-Code controlled device. A computer running a numeric controller and G-Code interpreter is connected to standard stepper motors. As G-Code commands are delivered, the magnetic field generated by the transmitted signals is read by a Hall Effect sensor. The rapid oscillation of the magnetic field corresponds to the stepper motor control signals which rhythmically move the motor. The oscillating signals are recorded by a high speed analog to digital converter attached to a second computer. The two systems are completely electronically isolated. The recorded signals are saved as a string of voltage data with a matching time stamp. The voltage data is processed through a Matlab script which analyzes the direction the motor spins and the number of steps the motor takes. With these two pieces of data, the G-Code instructions which produced the motion can be recreated. The demonstration shows the exposure of previously encrypted data, allowing for the unauthorized production of parts, revealing a security flaw in a distributed additive manufacturing environment. / Master of Science / Developed at the end of the 20th century, additive manufacturing, sometimes known as 3D printing, is a relatively new method for the production of physical products. Typically, these have been limited to plastics and a small number of metals. Recently, advances in additive manufacturing technology have allowed an increasing number of industrial and consumer products to be produced on demand. A worldwide industry of additive manufacturing has opened up where product designers and 3D printer operators can work together to deliver products to customers faster and more efficiently. Designers and printers may be on opposite sides of the world, but a customer can go to a local printer and order a part designed by an engineer thousands of miles away. The customer receives a part in as little time as it takes to physically produce the object. To achieve this, the printer needs manufacturing information such as object dimensions, material parameters, and machine settings from the designer. The designer risks unauthorized use and the loss of intellectual property if the manufacturing information is exposed. Legal protections on intellectual property only go so far, especially across borders. Technical solutions can help protect valuable IP. In such an industry, essential data may be digitally encrypted for secure transmission around the world. This information may only be read by authorized printers and printing services and is never saved or read by an outside person or computer. The control computers which read the data also control the physical operation of the printer. Most commonly, electric motors are used to move the machine to produce the physical object. These are most often stepper motors which are connected by wires to the controlling computers and move in a predictable rhythmic fashion. The signals transmitted through the wires generate a magnetic field, which can be detected and recorded. The pattern of the magnetic field matches the steps of the motors. Each step can be counted, and the path of the motors can be precisely traced. The path reveals the shape of the object and the encrypted manufacturing instructions used by the printer. This thesis demonstrates the tracking of motors and creation of encrypted machine code in a simulated 3D printing environment, revealing a potential security flaw in a distributed manufacturing system.

The motivation of this research is the need for reducing time and cost associated with maintaining information and communication technology infrastructure for design and manufacturing in digitally networked environments, enhancing design communication and collaboration in distributed and collaborative design processes, and adapting to rapidly changing market demands. The objective of this dissertation is to propose a new design and manufacturing paradigm, namely, Cloud-Based Design and Manufacturing (CBDM), for enhancing collaborative product development in distributed settings. In this dissertation, the following challenges pertaining to CBDM are addressed: the systematic development of a conceptual framework and a holistic vision for CBDM systems; the development of a new approach for visualizing distributed and collaborative design processes, measuring tie strengths in a complex and large design collaboration network, and detecting design communities with common design activities in cloud-based design (CBD) settings from a social network perspective; and the development of a new approach that helps identify potential manufacturing bottlenecks and scale manufacturing capacity in cloud-based manufacturing (CBM) settings from a manufacturing network perspective. The contributions of this dissertation are categorized in three research domains: (1) proposing the first definition, a holistic vision, and an example of application scenario for CBDM, (2) modeling and analyzing information flow in cloud-based design for improving design collaboration, and (3) modeling and analyzing material flow in cloud-based manufacturing for planning manufacturing scalability.

This diploma thesis deals with the creation of a general communication interface between the smart product and process cells within test bed Barman. The aim is to create distributed production according to the Industry 4.0 concept, where each product manages it’s production itself. The first part deals with the analysis of test bed, where are discussed requirements and method of production. Then with the selection of a communication protocol that would meet Industry 4.0 and distributed control requirements. The result of the research was OPC UA communication protocol. Using this protocol, the product and the process cell will communicate with each other. I chose the appropriate implementation for the selected protocol to be used for creating communication modules of the product and the process cell. Production data will be stored in an RFID chip located in the product. Part of the work is devoted to creation this data structure, which contains the recipe as well as production state data. Creation of RFID reader is the work of another student, with whom I solved the method of data exchange between application of the reader and the communication module of the product. When creating a communication module of the process cell, I solved the design of an information model that describes the entire process cell, and the dynamic creation of nodes in the address space. I have mentioned a few examples of how I worked with a selected implementation of OPC UA and how I used it in both applications. I implemented decentralized search of another process cells in the local network. This feature was easy to implement with OPC UA, specifically with the LDS-ME service. I solved the control of production for the communication module of the product and method of communication with the process cell. And in the last part I deal with manual, which describes how to compile projects correctly, specifically on the Linux operating system, and I have described a way to test the whole solution together with the results.

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Workload control (WLC) systems constitute a framework mainly for the inputoutput control systems which regulate both jobs&rsquo / queues into the workshop and the flow of finished goods out of the workshop. This study is concerned with the job entry and release level of WLC which maintains a pool of unreleased jobs for the controlled release of jobs. While most of the studies in WLC concepts deal with the centralized workload control, our study decentralizes the job entry and release control and makes workstations more powerful in schedule decision making. Job&rsquo / s information is sent to the workstations by mediator which is the supervisor of the workstation. Both mediator and work stations are represented by agents in a distributed system. Jobs&rsquo / routing information is assumed to be known in advance. The developed system is verified and validated by means of test runs. Results are analyzed as well.

[pt] Esta pesquisa examina as potencialidades e limitações da manufatura aditiva na produção de dispositivos médicos em resposta à crescente demanda global durante a pandemia da COVID-19. A pesquisa busca entender as implicações da adaptação de projetos, da conformidade com regulamentações e da criação de uma cadeia de produção resiliente e sustentável, utilizando impressoras 3D de baixo custo. Além disso, a pesquisa incita reflexões sobre a intersecção entre medicina e design, instigando novas pesquisas neste campo interdisciplinar. O estudo se aprofunda na análise de adaptações de design e na exploração de uma cadeia produtiva alternativa mais resiliente e com menor impacto ambiental. A pesquisa considera a possibilidade de utilizar resíduos hospitalares como matériaprima para a produção de componentes médicos, uma prática que pode reduzir custos de descarte e a pegada de carbono. Além disso, discute a implementação do DRAM (Design, Reciclagem e Manufatura Aditiva Distribuídos) em ambientes hospitalares para responder às demandas de saúde em cenários de interrupção da cadeia de suprimentos. A pesquisa levanta questões importantes sobre a fronteira entre medicina e tecnologia, destacando a importância da responsabilidade ética e social na evolução científica e tecnológica. Argumenta a importância da manutenção adequada dos equipamentos médicos e o papel vital que a manufatura aditiva pode desempenhar na produção rápida de peças de reposição, especialmente em situações de emergência, como a pandemia da COVID-19. Com uma análise detalhada do joelho, um projeto prático desenvolvido durante o mestrado, a pesquisa identifica a necessidade de reestruturação dos processos de fabricação, considerando fatores econômicos e geográficos. A experiência do projeto instigou discussões enriquecedoras sobre o papel do designer, a potência da tecnologia de fabricação digital e a relevância dessa atividade em situações de emergência. Finalmente, a pesquisa conclui que a Reciclagem Distribuída e a Manufatura Aditiva (DRAM) podem se apresentar como uma solução sustentável e descentralizada para a produção de itens críticos em hospitais. Sugere a possibilidade de implementação de um ciclo fechado de produção e consumo de materiais através da fabricação de filamentos a partir de resíduos no próprio local de cuidados de saúde. Isso não só reduziria a dependência de fornecedores externos e a pegada ambiental da produção, mas também poderia melhorar a eficiência e agilidade dos sistemas de saúde em situações de emergência. / [en] This Master s dissertation examines the potentialities and limitations of additive manufacturing in the production of medical devices in response to the growing global demand during the COVID-19 pandemic. The research seeks to understand the implications of project adaptations, compliance with regulations, and the creation of a resilient and sustainable production chain, using low-cost 3D printers. Furthermore, the research instigates reflections on the intersection between medicine and design, stimulating new research in this interdisciplinary field. The study delves into the analysis of design adaptations and explores an alternative production chain that is more resilient and has less environmental impact. The research considers the possibility of using hospital waste as raw material for the production of medical components, a practice that can reduce disposal costs and the carbon footprint. In addition, it discusses the implementation of DRAM (Distributed Recycling and Additive Manufacturing) in hospital environments to respond to health demands in scenarios of supply chain disruption. The research raises important questions about the frontier between medicine and technology, highlighting the importance of ethical and social responsibility in scientific and technological evolution. It argues the importance of proper maintenance of medical equipment and the vital role that additive manufacturing can play in the quick production of replacement parts, especially in emergency situations, such as the COVID-19 pandemic. With a detailed analysis of the elbow, a practical project developed during the master s program, the research identifies the need for restructuring manufacturing processes, taking into account economic and geographic factors. The project s experience instigated enriching discussions about the role of the designer, the power of digital manufacturing technology, and the relevance of this activity in emergency situations.