Paul Christoph Gembarski

Leibniz Universität Hannover · Institute of Product Development

Ecosystems have the promising potential to respond to economic but also environmental and social challenges, such as by enabling circular thinking, establishing fair supply chains, responsible collaborations, and ensuring resilience. In this report, we summarize findings from multiple data sources in the context of the NaWerSys workshop series whic...

Computational design systems offer diverse opportunities for capturing and reusing engineering knowledge and design intent. Two approaches are knowledge-based computer-aided design (CAD) and algorithmic modeling. While the first uses mathematical and logical constraints, design rules, and reasoning to control the parameters of a CAD model, the latt...

To enable product customization, validating the design solution spaces is necessary to ensure safe manufacturing and operation. Implementing product models with component families to choose from serves as a basis for tools such as product configurators. Today, advancements in production technology, digital functionalities of products, and emerging...

Parametric and chronology-based CAD system are still predominantly in use in mechanical engineering. Although this modelling principle simplifies the creation of changeable part and assembly models, there is only little scientific literature dealing with the implementation of advanced parameter control concepts. In this article, the authors discuss...

With rising customization demands, optimizing flexibility, productivity, and cost is essential. Traditional specialized processes are time-consuming and costly, especially when errors emerge during assembly. This paper introduces a multi-agent system (MAS) for automated assembly sequence generation. The system combines and complements existing sequ...

During refueling supercritical hydrogen into high pressure storage tanks, the fluid has to be cooled down to temperatures between -33°C and -40°C before entering the vehicle fuel tank. This cooling takes place while the hydrogen is at a pressure of up to 87.5 MPa. The requirements for the heat exchanger performing this task are very high. It has to...

Configuring complex computer-aided design (CAD) assemblies just by modifying parameters requires the attention and abstraction of the users. This interaction cost can be lowered significantly by graphical interactive control elements that allow for drag and drop modifications directly in the 3D assembly. Contributing techniques, such as working wit...

Prosthetic implants, particularly hip endoprostheses, often lead to stress shielding because of a mismatch in compliance between the bone and the implant material, adversely affecting the implant’s longevity and effectiveness. Therefore, this work aimed to demonstrate a computationally efficient method for density-based topology optimization of hom...

The increasing complexity in product development and the lack of knowledge exchange, for example, between development and manufacturing lead to unnecessary iteration loops and high costs. To overcome this situation, an option is the execution of a design review using multi-agent systems to provide designers with a digital assistance system for chec...

This paper presents a computer-aided modeling strategy to formalize process chain knowledge, such as the design of manufacturing stages, cross-process manufacturing constraints or manufacturing tools, for product design and to provide it for product and process design decisions in the context of design for manufacturing. Using the example of a tail...

To satisfy individual customer requirements, products with many options are offered in mass customization. Particularly in the case of variant designs for small batch production, the design or configuration of the possible options implies additional effort. Therefore, a knowledge-based engineering system as a multi-agent system is created in this p...

Anthropometric product individualization can maximize customer value and is becoming increasingly economical due to advanced developments of digital process chains. This paper provides a case study of two individualization services, primarily addressing data plausibility and solution space modelling. The contribution is identifying relevant guiding...

The trend towards product individualization in medical technology, e.g., for implants, is based on the realization that taking patient-specific characteristics into account significantly influences the therapy of diseases. However, one problem in the individualization of implants is the inaccessible position in the body, which only permits computer...

Rainwater harvesting attracts growing interest from the field of municipal planning. When considering a rainwater harvesting system as a design object, questions include whether the system is designed for a single property or for a local water network serving multiple properties, what allows for the inclusion of buffer tanks and resource balancing...

The design of components suitable for manufacturing requires the application of knowledge about the manufacturing process chain with which the component is to be manufactured. This article presents an assistance system for decision support in the context of design for manufacturing. The assistance system includes explicit manufacturing process chai...

The repair of defective metal parts using additive manufacturing processes (additive repair) instead of disposal offers the potential to manufacture parts more cost-effectively, faster, and in a way that preserves resources. One hurdle to a broader application of additive repair is that users without expertise in additive repair lack adequate guida...

For an ergonomic and healthy sitting posture, the distribution of the seat load in the contact zone through a soft seat cushion is essential. Conventional polyurethane (PUR) foams have only a very limited ability to adapt the distribution of the seat load in the seat cushion to the individual person. In this paper, a potential analysis is conducted...

Additive manufacturing is a strong enabler for the individualization trend in product development and is also increasingly finding its way into medical technology. This is made possible by the immense design freedom as well as new modeling methods, which can transform the design phase in product development. This paper presents a process chain for...

With the help of effect-engineering, highly efficient additively manufactured products with a high-power density can be designed. The potential of product development lies in the conceptualization design and embodiment design phases, which have, however, only been methodically analyzed to a limited extent. Effect-engineering offers the possibility...

In order to avoid errors in engineering design that affect the later product life cycle, especially the manufacturing process, an analysis or evaluation has to be performed at the earliest possible stage. As this evaluation is very knowledge-intensive and often this knowledge is not directly available to the engineer, this paper presents an approac...

The deep-drawability of a sheet metal blank is strongly influenced by the tribological conditions prevailing in a deep-drawing process. Therefore, new methods to influence the tribology represent an important research topic. In this work, the application of a process-integrated lubrication in a deep-drawing process is investigated. Most promising g...

When developing products, engineers face challenges in solving technical, economical, but also ecological conflicts of objectives. A common technical conflict is the contradictory behaviour between the stiffness and mass of components. A possibility to resolve this contradiction is offered by multi-material components, which are made possible by a...

Design automation systems often mimic human designers and implement routine design activities. Beside this, the idea of such knowledge-based engineering is to support developers in the analysis and syntheses of complex engineering artifacts. An instance of this is product configuration. A central aspect of knowledge-based engineering is its ability...

Knowledge-based geometry models reduce variant design to the input of parameter values. Especially knowledge-based CAD models that incorporate geometrical data and implemented explicit knowledge offer additional possibilities. One is interactive drag-and-drop control of geometric features. This poses new requirements for the setup of CAD models as...

In order to meet a wide range of customer requirements in product development, a high degree of individualization is necessary today, which can be achieved with product configuration systems. Knowledge-based CAD models are a useful tool for implementing such configurators, but they are significantly more complex to develop than conventional paramet...

During product development, changes to parts that are already built into assemblies usually lead to the need to check the function and consistency of the assembly. This procedure is very time-consuming and has to be performed again for each change. In this paper, an approach is presented in which the individual parts are represented as agents that...

In configuration design, the task is to compose a system out of a set of predefined, modu-lar building blocks assembled by defined interfaces. Product configuration systems, both with or without integration of geometric models, implement reasoning techniques to model and explore the resulting solution spaces. Among others, the formulation of constr...

Expert systems enable the automated solution synthesis for complex product classes. Particularly to be highlighted in this area is the Computational Design Synthesis (CDS), which automatically designs, evaluates and guides solutions. Thus, individualized osseointegrative implants can be generated in one single step on the basis of CT scans. This pa...

The idea of knowledge-based engineering is to widely automate design tasks and support developers in the analysis and syntheses of complex engineering artifacts. A very common application is product configuration. In the past, different reasoning techniques have been proposed, one of them model-based reasoning and in particular constraint satisfact...

Zusammenfassung Spätestens seit Beginn der Corona-Pandemie ist eine Vielzahl von Unternehmen aufgrund von Social-Distancing-Maßnahmen und neuen Mitarbeiteranforderungen mit hybrider Arbeit als neuem Status Quo konfrontiert. Während hierin absehbar das Potenzial zur generellen Flexibilisierung von Arbeit liegt, müssen Arbeitgeber veränderte Formen d...

During product development, many decisions have to be made that affect the entire product life cycle and often lead to errors that cause additional effort. To proactively support the engineer in evaluating his design in a CAD program, in this paper an approach to evaluate milling designs using a multi-agent system (MAS) is presented. The CommonKADS...

Endoprosthesis are exposed to the risk of aseptic loosening. The design of the prosthesis shaft to achieve physiological force application is therefore of great importance. Additive manufacturing offers the potential to fabricate highly variable topologies, but challenges the designer with a large number of design variables. In this work, a method...

For the economic use of repair in the spare parts business, additive repair by Laser Powder Bed Fusion (LPBF) is a promising technology. As material can only be applied to a flat surface in LPBF, prior machining is required. The selection of the section plane requires expert knowledge, though. To provide that knowledge and recommend a suitable sect...

Marketing, production and operation of product-service systems require many different competencies and open up different directions for optimization. However, as in traditional product businesses, not all services from the extraction of raw materials and their refinement through to delivery and maintenance will be provided by a single supplier, but...

In the age of digitization and data-driven technologies, business models around physical products, regardless of whether smartphone or industrial printing machine, are not limited to sale or the offering of accompanying services like maintenance contracts. Rather, new offerings regard the product itself already as a platform for value creation, thu...

To link the two research fields of Sustainable Development and Mass Customization (MC), areas like enablers and impact factors, business models for sustainable MC and analyzing or nudging consumer purchase decisions are often themed. Robust process design as MC key competence allows a different view on this, putting process-oriented and resource-ba...

Repairing defective parts offers the potential to provide spare parts more cost-effectively, faster and with less use of resources. High process reliability and reproducibility in the repair of metallic parts can be achieved by using additive manufacturing. However, additive repair has only been used in a few cases for the maintenance of parts. For...

During product development, many decisions have to be made which affect the entire product life cycle. Especially in early phases in product development these decisions are subject to uncertainties when involving customer specific requirements. To support the designer in developing robust products that are insensitive to uncertainty, this paper com...

Increasing the efficiency of designers indirectly affects the price of offered goods. Particularly in the case of variant designs for small series production, it is advantageous to automate repetitive activities as completely as possible during the respective development cycles. As known from Mass Customization, knowledge-based configurators are an...

Roth’s design catalogue was developed particularly as repository for engineering knowledge also for the early phases of the design process and as a methodological support for the designer. Design catalogues are not only a simple collection of known and proven solutions for design problems but allow for structuring and prioritizing solutions accordi...

In the digital era, individualized educational services, e.g. distributed by intelligent tutoring systems, are becoming increasingly popular and important for life-long learning but also during the COVID pandemic as many universities had to switch to distance learning immediately. Intelligent tutoring systems simulate behavior and expertise of phys...

In the field of medical technology is a continuous trend towards product individualization. This trend depends on the realization that the patient's characteristics, as well as the influences of the individual lifestyle and the environment, have a significant influence on the respective disease and its possible therapy. For this purpose, this paper...

During product development, many decisions have to be made which affect the entire product life cycle. In order to check whether the product meets the requirements, design reviews are carried out. One difficulty here is the sustainable storage and application of decentralized expert knowledge. To support the engineer proactively in the design proce...

With the development of new technologies, such as smart components, additive manufacturing or multi-materials, product performance tests play a decisive role on supporting effective design and product reliability. However, test machines are mostly designed to attend norms and perform standard tests, which requires a need for development of new mach...

Making design decisions is characterized by a high degree of uncertainty, especially in the early phase of the product development process, when little information is known, while the decisions made have an impact on the entire product life cycle. Therefore, the goal of complexity management is to reduce uncertainty in order to minimize or avoid th...

Das Erreichen der Nachhaltigkeitsziele der Vereinten Nationen stellt eine der wichtigsten Herausforderungen der heutigen Zeit dar, welche Transformationen in Gesellschaft und Wirtschaft unumgänglich machen. Die Entwicklung innovativer Geschäftsmodelle und deren Umsetzung in sich stetig neu bildenden Wertschöpfungssystemen spielen bei dieser Transfo...

In the event of damage to additively manufactured components whose shape cannot be produced by machining, an additive repair can potentially be not only ecologically but also ecologically more favorable than the production of a new component. In addition, a number of hurdles that otherwise often impede the use of additive repair, e.g. the availabil...

One of the arguments against an increased use of repair is that, due to the constantly growing progress, an often already outdated component would be restored. However, refurbishment also allows a component to be modified in order to upgrade it to the state of the art or to adapt it to changed requirements. Many existing approaches regarding Design...

Viele Bauteile erreichen aufgrund eingeschränkter Möglichkeiten zur Wartung und Instandhaltung vorzeitig ihr End-of-Life. Additive Fertigungsverfahren bieten jedoch die Möglichkeit, Bauteile zu reparieren, die bisher als nicht reparabel galten. Weiterhin können Bauteile in der additiven Reparatur optimiert werden, sodass z. B. das Wartungsintervall...

In mechanical engineering, robust solutions have to be determined from open and ill-structured solution spaces. In order to actively support the engineer in this decision-making, multi-agent systems represent a promising approach for modular, decentralized, changeable, and complex tasks. To identify existing use cases of multi-agent systems in prod...

In der Endoprothetik können konfektionierte Kurzschaftprothesen die anatomischen und osteologischen Anforderungen an die Standzeit, Funktionalität und Komplikationsfreiheit nicht optimal erfüllen. Dieser Beitrag bietet die Spezifikationen für eine rechnerunterstütze Entwicklungsumgebung zur Synthese einer patientenindividuellen Kurzschaftendoprothe...

Durch fertigungsbedingte Restriktionen wird der Gestaltungsraum von mechanischen Bauteilen während der Produktentwicklung eingeschränkt. Die Einschränkungen sind in der Regel nicht vollständig bekannt und können daher nicht in vollem Umfang bei der Bauteilgestaltung berücksichtigt werden. Das betrifft insbesondere prozessübergreifende Fertigungsres...

Die digitale Transformation von Geschäftsmodellen entlang visionärer Anwendungsszenarien, wie der Industrie 4.0 und Smart Services, erlauben Branchen wie dem Maschinen- und Anlagenbau das Heben neuer Wertschöpfungspotenziale. Dabei bildet die Evolution von physischen Produkten, ausgehend von rein mechanischen, über mechatronischen, bis hin zu cyber...

Die derzeit in Wissenschaft und Praxis geführte Debatte um nachhaltige und nutzenstiftende IoT-basierte Geschäftsmodelle fokussiert häufig ausschließlich die technisch-physischen Komponenten des Leistungssystems. Ihrer Natur und dem Kundenbedürfnis entsprechend bestehen diese Leistungsbündel jedoch aus zwei Teilen: (Vernetzten) Produkten und (digit...

The use of knowledge-based engineering is moving further into the focus of product development due to a growing discussion on the topic of artificial intelligence. The field of application of the systems mainly includes the synthesis of design artifacts such as the automatization of routine tasks. In this paper an "inverse" application of knowledge...

In der Produktentwicklung gelten diverse Richtlinien, an denen sich Ingenieure orientieren. Letztendlich sind aber die Erfahrungen des jeweiligen Anwenders dafür verantwortlich, ob eine Konstruktion korrekt gestaltet wird. Dieser Beitrag bietet einen Ansatz zur automatisierten Anwendung dieses Erfahrungswissens durch die Objekterkennung mittels Dee...

The use of multi-material forming components makes it possible to produce components adapted to the respective requirements, which have advantages over mono-material components. The necessary consideration of an additional material increases the possible degrees of freedom in product and manufacturing process development. As a result, development b...

In mechanical engineering, designers have to review a designed artefact iteratively with different domain experts, e.g. from manufacturing, to avoid later changes and find a robust, optimized design. To support the designer, knowledge-based engineering offers a set of approaches and techniques that formalize and implement engineering knowledge into...

For the satisfaction of individual customer requirements, products with many options are offered in mass customization. However, in the area of e-commerce, the large number of possible product configurations can overwhelm the customer, as he or she is not supported by a human sales expert. To minimize the customer's overload, this paper examines th...

Choice navigation, solution space development and robust process design are the three mass customization key competences. The first and second are often mapped into product configuration or design automation systems and aim at specifying or co-designing a suitable product variant. Robust process design targets at managing a well-known but flexible...

A common description of Mass Customization is offering individual, customer-specific product variants with mass production efficiency which targets both at manufacturing and distribution. In order to do so, defined degrees of freedom are introduced into a product model or portfolio which are restricted by choices and decisions a customer makes in a...

Product configurators are a widely used tool to let customers specify an individual variant that best fits to their requirements. The basis for this is a product model that has well defined degrees of freedom and options and so describes the possible solution space. Related to this are design automation systems that aim at automating the design pro...

Product Service Systems (PSS), can be considered as mass customization business models with an extended time horizon. For the development of such customer-specific hybrid value propositions, small and medium-sized enterprises (SME) face the challenge of identifying relevant potential for PSS in their areas of competence, as they often lack capaciti...

The goal of decision making is to select the most suitable option from a number of possible alternatives. Which is easy, if all possible alternatives are known and evaluated. This case is rarely encountered in practice; especially in product development, decisions often have to be made under uncertainty. As uncertainty cannot be avoided or eliminat...

To develop problem-solving skills during engineering studies, students must be given the opportunity to act independently and to apply their expertise in professional application situations with feedback that promotes learning. Although practical projects in university teaching deal with real-world problems, individual support and promotion of the...

The application of computer-aided design (CAD) systems belong to the very basic competences that a design engineer in mechanical engineering is taught. The definition of shape and product properties in such systems is the foundation of virtual prototyping and the later manufacturing as well. Depending on the specialization, there exist different ca...

For manufacturers of capital goods who aim to bring competitive and profitable products to the market, it is beneficial to optimize the products with regard to the costs that arise over their entire life cycle. Especially in the early development phase, decisions that are primarily made to reduce initial costs must be compared with the resulting fo...

Die Verfahren der additiven Fertigung haben sich in vielen Branchen zur Herstellung komplexer Bauteilgeometrien, auch über den Prototypenbau hinaus, etabliert und tragen zum Erhalt der Innovationsfähigkeit des Maschinen- und Anlagenbaus bei. Die Geschäftsmodelle des Maschinenbaus wandeln sich jedoch von der klaren Produktorientierung hin zu kundeno...

Knowledge-based engineering (KBE) systems allow an easy adaption of designed artefacts to new functional or design requirements and automating routine design tasks. In the following article the author wants to focus on the three main concepts of linking CAD and KBE and answer the research questions (1) in which way is integration, embedding and cou...