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Due to their growing amount and heterogeneity, we need a precise and standardized understanding about the foundation, structure, and forms of aggregation and especially the use of data and models within the production domain. Our aim is to investigate how to model data elements and static and dynamic relationships as well as their physical resources in the IoP, in a cross-disciplinary life cycle spanning cooperation as a basis for information management, meeting all technical, scientific-ethical, and legal framework conditions. The core solution for this challenge is the use of an adequate set of modeling techniques, transformations, and their integration with digital shadows. This chapter provides a deep insight into relevant concepts that constitute a digital shadow, link it to their semantics defined by appropriate metamodels, and discuss the data and models a digital shadow consists of in four use cases. We show a method to derive digital shadows and introduce their life cycle in relation to the product life cycle. These concepts are the foundation for data and model sharing within digital shadows applicable for worldwide production labs.

In the injection molding process of semi-crystalline thermoplastics, the melt is subjected to a complex deformation and temperature history. This leads to an inhomogeneous microstructure over the component and thus to local inhomogeneities in the component’s effective properties. To predict the component properties precisely, a multi-scale simulation is used, which couples the filling simulation at the component level with a microstructure simulation at the scales of microns (SphaeroSim). The influence of the crystallization heat is considered in the filling simulation with an averaged empirically determined degree of crystallization. To achieve higher precision in the microstructure simulation the influence of the crystallization heat is considered at the microscale of SphaeroSim. SphaeroSim is extended by the calculation of a local crystallization degree, which is used to calculate the amount of local crystallization heat and heat transport calculations.

The demand for precise injection molded parts is continuously increasing. One of the main effects that negatively influence the geometrical part properties is warpage due to inhomogeneous shrinkage. By homogenizing the specific volume and thus the shrinkage potential, warpage is expected to be reduced. The following work addresses the homogenization of the specific volume by controlling the local part temperature with 18 individual tempering zones in the mold, which are capable of rapid heating and cooling.

Smart manufacturing demands to process data in domain-specific real-time. Engineering models created for constructing, commissioning, planning, or simulating manufacturing systems can facilitate aggregating and abstracting the wealth of manufacturing data to faster processable data structures for more timely decision making. Current research lacks conceptual foundations for how data and engineering models can be exploited in an integrated way to achieve this. Such research demands expertise from different smart manufacturing domains to harmonize the notion space. We propose a conceptual model to describe digital shadows, data structures tailored to exploit models and data in smart manufacturing, through a metamodel and its notion space. This conceptual model was established through interdisciplinary research in the German excellence cluster “Internet of Production” and evaluated in various real-world manufacturing scenarios. This foundation for an understanding helps to manage complexity, automated analyses, and syntheses, and, ultimately, facilitates cross-domain collaboration.

The thermal design of injection moulds is a complex process and is often conducted manually by the mould maker. However, manufacturing of highly precise parts has become more and more important over the last years. The focus is laid especially on part warpage and reproducible results in the context of a stable process.

The production of plastic optics creates great challenges for the injection moulding process. The lens geometry is designed to fulfil the optical requirements and often contradict the plastic design guidelines. Especially thick-walled lenses with changes in wall thickness are challenging not only in the classic injection moulding process but also in injection-compression moulding processes, as the compression pressure can lead to internal stresses and thus to reduced optical properties. In order to increase the optical performance of thick-walled plastic lenses, a methodology developed at the Institute of Plastics Processing is being adapted for the inverse calculation of the cooling requirements of plastic components. Based on this, a cooling channel design is derived and validated in injection moulding simulations. With this method, lower peak values of residual stress and birefringence can be achieved. Furthermore, it can be shown that the developed cooling channel layout significantly reduces the cooling time required to reach the glass transition temperature.

Digital Twins (DTs) of Cyber-Physical Production Systems (CPPSs) enable the smart automation of production processes, collection of data, and can thus reduce manual efforts for supervising and controlling CPPSs. Realizing DTs is challenging and requires significant efforts for their conception and integration with the represented CPPS. To mitigate this, we present an approach to systematically engineering DTs for injection molding that supports domain-specific customizations and automation of essential development activities based on a model-driven reference architecture. In this approach, reactive CPPS behavior is defined in terms of a Domain-Specific Language (DSL) for specifying events that occur in the physical system. The reference architecture connects to the CPPS through a novel DSL for representing OPC-UA bindings. We have evaluated this approach with a DT of an injection molding machine that controls the machine to optimize the Design of Experiment (DoE) parameters between experiment cycles before the products are molded. Through this, our reference implementation of the DT facilitates the time-consuming setup of a DT and the subsequent injection molding activities. Overall, this facilitates to systematically engineer digital twins with reactive behavior that help to optimize machine use.

Within the further development of a special mechanical representation of the human circulatory system the CVELoop at the Department of Cardiovascular Engineering at RWTH Aachen University, a contractive MockHeart was developed. This MockHeart simulates a healthy heart in the CVELoop. In opposition to all previous cardiovascular system simulators, the left ventricle is externally driven by several cam mechanisms. These cam mechanisms provide the necessary power to create the pressure-volume-work for the fluid circulation but also the important time dependent radial contraction, which is the most influential degree of Freedom in the human heart. The aim is to produce a MockHeart providing valid boundary conditions for the connected VAD (Ventricular Assist Device). The systematic approach of the development of the mechanism is performed based on an accurate measurement of the kinematic properties of a healthy human heart at RWTH Aachen University with the speckle tracking echocardiography-procedure.

Customer demands have become more individual and complex, requiring a highly flexible production. In high-wage countries, efficient and robust manufacturing processes are vital to ensure global competitiveness. One approach to solve the conflict between individualized products and high automation is Model-based Self-optimization (MBSO). It uses surrogate models to combine process measures and expert knowledge, enabling the technical system to determine its current operating point and thus optimize it accordingly. The objective is an autonomous and reliable process at its productivity limit. The MBSO concept is implemented in eight demonstrators of different production technologies such as metal cutting, plastics processing, textile processing and inspection. They all have a different focus according to their specific production process, but share in common the use of models for optimization. Different approaches to generate suitable models are developed. With respect to implementation of MBSO, the challenge is the broad range of technologies, materials, scales and optimization variables. The results encourage further examination regarding industry applications.

The research area “Integrative Computational Materials and Production Engineering” is based on the partial integration of individual models areas within separated simulation platforms with the objective of further development and integration into a single comprehensive ICMPE (Integrative Computational Materials and Production Engineering) platform that combines materials and machining simulation with factory and production planning. In order to realize an operational platform concept, the AixViPMaP has been implemented. AixViPMaP serves as a technology platform for the knowledge-driven design, implementation and improvement of complicated process chains for materials in high-value components. This allows manufacturing related influences to be considered during production in order to optimize process performance and materials properties. The extension and application of the AixViPMaP platform towards production modeling in the sense of an ICMPE based on one holistic system integrates production related models with all material-related models into a single, unified concept. Advanced test cases are under examination to validate and assess this new integrated approach (e.g., new alloys for large gears for the wind industry).

Mold-based production systems are vastly common in mass production processes, due to the high investment costs of production equipment. In order to address the challenge of a strong tendency towards individualized customer demands, companies in high-wage countries are forced to react towards these changes. This chapter describes recent advances in the field of individualized production for mold-based production systems regarding plastics profile extrusion and high-pressure die casting. A holistic methodology for an integrated product and mold design is presented based on the principles of simultaneous engineering. In addition, recent advances in the field of numerical optimization are shown. The advances in numerical optimization will be carried out based on the processes mentioned above. The monitoring and simulation of the viscoelastic swell will be shown for plastics profile extrusion. For the field of high-pressure die casting the strategy to optimize the entire process will be outlined and current experimental results shown. For both application cases the potential benefit of additive manufacturing technologies—such as Selective Laser Melting (SLM)—will be evaluated and validated inasmuch as possible.

Development of technical solutions that lead to widening the use of multi-technological products as well as in assessing ecological and economic potentials of multi-technological products have not yet been studied intensively. The activities conducted in the context of this research area focus on these aspects. The aforementioned aspects have been examined, evaluated and quantified on the basis of three example products resulting from the first funding period. The research activities conducted on the example components deliver the basis for the layout of different integrated multi-technology production systems. Technical solutions that enable coupling of different process steps with each other as well as the integration of different functionalities and different materials in final multi-technology products have been proposed. The complex interdependencies of the products themselves and their associated production processes have been researched and evaluated intensively. Finally, a profitability assessment of the proposed solutions was conducted and future research topics identified.

The integration and combination of known production technologies to one-step-processes is a promising way to make existing processes more efficient and to enable more integrated products. This paper presents two integrative process technologies that are developed by the Institute of Plastics Processing (IKV) and the Surface Engineering Institute (IOT) as part of the Cluster of Excellence “Integrative Production Technologies for High-Wage Countries”. In these processes, metals or metal alloys are applied to an injection moulded part, which results in a new opportunity to create electrical conductivity of plastic articles. The Integrated-Metal-Plastic-Injection-Moulding (IMKS) represents the combination of injection moulding and metal die-casting, allowing the production of plastic parts with integrated conductive tracks in one shot. The In-Mould-Metal-Spraying (IMMS) combines the injection moulding with the thermal spraying of metal. Therefore it is possible to equip electrically insulating plastic parts with metallic coatings and provide an electromagnetic shielding like cast metal parts. In the following both processes are presented and future potentials and challenges are shown.