The current energy crisis and high fossil fuel costs are challenging energy intensive industries such as non- ferrous foundries. It is therefore important to promote the transition to renewable energy sources with the electrification of melting units. This pilot study is the first to simulate the transition of conventional foundries to sustainable technologies. For this purpose, a simulation model based on a selected example company is developed. It takes into account the energy consumption and the logistical effects of a converted operation. The simulation model is implemented as a hybrid simulation combining a discrete event simulation at the plant level and a process simulation within the furnaces. The study shows how a sustainable energy supply can be achieved in foundries. The effects of efficiency as well as energy costs and emissions are also taken into account.

LCD technology has been known for decades and used in the manufacture of components with photosensitive material (6K, 8K, polyurethane- based elastics resin, eco- and bioresins). The functional characteristics and aesthetics of components can be improved by adding reinforcing materials in the form of powders, pigments, or other additives. The paper presents the effects on the printing process with such a modified resin through a systematic approach. The modifications consisted in adding metallic powders with two different grain size (aluminum and copper). The results showed not only the possibility of successful printing but also problems that can occur during the processes. Several tests were carried out on a desktop LCD 3D printer, which makes the proposed approach applicable to any type of equipment.

One of the common welding methods for polymer rooftop sheets is the overlap welding by hot air either done manually for small parts or with a welding machine for long sheets. The weld quality depends on different parameters like the welding speed, the welding temperature or the pressure applied on the joining materials. Due to the field of application of rooftop sheets, there are other environmental influences like the ambient temperature, the air humidity or direct sunshine which can cause a decrease of the welding quality. This work will focus on a pre welding influence, the storage temperature of the rooftop sheets and how it affects the welding quality. Two poly vinyl chloride (PVC) rooftop sheets were chosen and tested separately. The materials were cut into small sheets, stored under different temperature conditions, and were welded afterwards. The welded samples were tested according to the DIN EN 12317-2 to determine the shear resistance of the weld as it is an important mechanical property and a good indicator for the quality of the weld. The results show a minor influence on the welding process but no influence on the quality of the weld itself as all weld lines of all samples managed to stay intact

• Sinkende Studierendenzahlen im MINT-Bereich stellen ein Problem für die Hochschulen und die Gesellschaft dar. Die Ursachen liegen u.a. darin, dass sich die Schülerinnen und Schüler den MINT-Anforderungen zunehmend nicht gewachsen fühlen oder diese wenig attraktiv finden. Beidem kann durch zielgruppenspezifische Angebote an den HAWs begegnet werden. In der Fakultät Technik der Hochschule Ansbach wurde im Verlauf der letzten acht Jahre ein Konzept entwickelt, in dem Teilnehmende vom Vorschulalter bis zum Abitur altersgemäß in Laborversuchen mit allen Sinnen angesprochen werden. Das Maßnahmenpaket besteht aus verschiedenen Präsenzangeboten vom einfachen spielerischen Experimentieren für Vorschulkinder bis hin zu Vertiefungsworkshops und Schnupperangeboten für Teilnehmende aus den Oberstufen. Um die hohe zeitliche Belastung der einzelnen Hochschulangehörigen zu reduzieren, werden die Maßnahmen fakultätsintern koordiniert und unter Einbeziehung möglichst vieler Fakultätsmitglieder realisiert.

Fused Filament Fabrication builds parts layer-wise by depositing molten thermoplastic in the shape of filaments. Those are characterized by thickness and width. Together with the deposition speed, they determine the material flow. Depending on the extrusion system melting capacity and the considered materials, the flow can be limited to a certain degree, leading to under-extrusion. Slicing tools such as Cura allows filaments to overlap to compensate for under-extrusion and prevent voids formation. However, if the superposition is too high, the melt is squeezed out of the deposition path, affecting the surface quality. This study aimed to evaluate the influence of raster width, angle, overlap, and deposition speed over the top surface topography of samples printed of ABS, ASA, and PC. The results show that the rasters’ width and overlap significantly influence top surface topography. 

The current energy crisis and the high cost of fossil fuels pose major challenges for energy-intensive industries such as the non-ferrous foundry industry. Therefore, it is important to promote the transition to renewable energy sources with the help of the electrification of the melting units. In this pilot study, for the first time the conversion of conventional foundries to sustainable technologies is simulated. For this purpose, a simulation model is developed based on a selected example company. It considers the energy consumption and the logistical effects of a converted operation. The simulation model is implemented as a hybrid simulation combining a discrete
event simulation at the plant level and a process simulation within the furnaces. The study shows how a sustainable energy supply can be achieved in foundries. It also considers the impact of efficiency, energy costs and emissions.

Epoxy resins are widely used polymers in the automotive and aerospace fields. Different blends of novel biodegradable resins have been studied in the last years in order to provide sustainability while maintaining the same properties of epoxy resins. Bio-based thermoset resins made with acrylated epoxidized soybean oil are well-studied in different vat polymerization techniques. The present work compares a bio-based resin and a petroleum-based resin. A benchmark with different features was designed and manufactured by a VAT photopolymerization process using both materials; measured with an optical scanning device; thus, the dimensional deviations were analyzed through inspection software. Tensile and flexural specimens were manufactured with the same procedure and tested with a dynamometer machine. Therefore, the comparison between a biodegradable resin and a petroleum-based resin is discussed in terms of the quality and mechanical performances of manufactured parts, considering the use of identical printing conditions. Some parts are required to satisfy both the requirements at the same time, such as the gears. Therefore, dimensional accuracy and mechanical strength need to be controlled and evaluated in a unique final quantification. This work proposes a novelty performance index to quantify dimensional accuracy and mechanical strength simultaneously. By combining the two aspects it is possible to define the overall performance obtained with the used material, optimizing the manufacturing process by choosing the proper material for each purpose.

In spring 2022, we implemented e-portfolios at a product design course for engineers in the bachelor's programme on ‘Sustainable Engineering’ at the University of Applies Sciences, Ansbach. The use of e-portfolios was new to both students and lecturers. To evaluate the effect the e-portfolio had on students, we accompanied the implementation with surveys and interviews. This paper provides a comprehensive analysis of the evaluated results. Among other things, the following three main findings convinced us to continue with e-portfolio work. First, ~91% of the interviewed students felt that they were supported very well by our introduction. Second, ~93% got along well / very well with the functions of the e-portfolio software. Third, ~86% of those interviewed appreciated the freedom of design. Prior to the implementation of e-portfolios in our first test course, we identified the following factors as crucial for the successful implementation of e-portfolios: a comprehensive personal introduction, extensive information material, continuous guidance, clear work instructions, room for flexibility and creativity to foster learners' individual strengths, and exchange between learners and teachers. This paper reflects on these initial factors. The aspects identified for further improvement in the second round of e-portfolios, in the summer of 2023, are better technical preparation of the lecturers, the communication of technical borders in advance, timing of the accompanying e-portfolio workshops and a more comprehensive promotion of teamwork. The suggested modifications will be discussed in detail in this paper.

Students not always enjoy an in-depth practical learning experience with an adequate portion of hands-on during their academic education. In many fields of study, traditional laboratories are common learning spaces that are, however, not accessible 24/7 and, the practical work is mostly pre-defined by the lecturer, resulting in a short and very “passive” active learning. To overcome this limitation and to provide a broader availability and to foster individual learning experience, we aim to transform this analog world into a modern learning and teaching environment using digital technologies and a corresponding digital framework for courses and laboratories. An existing laboratory on prototyping from our university’s bachelor program on sustainable engineering with an extensive machine park consisting of 3D printers, milling machines, lasers and various hand tools is digitized and will finally be linked with the real-world lab. In addition to digitizing the basic process of product development and prototyping as part of students' project works, all additional activities arising in the lab are also transferred from the analog to the digital world. This digitalization is implemented alongside the already existing (partly browser-based) software tools of the individual devices in the e-learning platform Moodle. This results in a digital copy of the lab, its equipment and defined processes – structured in accordance with the established proceedings on product development (such as Pahl/Beitz and VDI 2221). We consider it a digital twin of the work and learning environment, calling it the “digital learning environment twin” of the real-world lab. For the product development process, a course area is available in Moodle with various feedback loops and assessment levels for the individual development steps of the student projects. Through this, students can submit their project plans, design ideas, sketches, CAD-models, manufacturing codes (such as G-codes for 3D printers, laser cutters and carving machines), or “just” request feedback and initiate meetings on technical and/or organizational topics of their product design process, the lab equipment, etc. Also, a safety instruction with instructional videos, PDF documents with hazard warnings and operating instructions as well as a final test (to allow operating the lab equipment) are provided to introduce the students to the lab. In this paper, we will illustrate the overall methodological approach on the established digital learning environment twin of the lab. Furthermore, we will have a detailed view on the challenge of transferring underlying manufacturing process to the digital world and linking them to provide a continuous digital workflow. The paper will be closed with an analysis of feedback (by both students and lecturers) on the pros and cons as well as on the usability of the digital twin of the lab.

In recent years multi-material Additive Manufacturing gained more interest as new applications were found in domains such as bioengineering, soft robotics and actuators, electronics and many more. Fused Filament Fabrication (FFF) is one of the most used AM technologies for multi-material 3D printing due to relatively low-cost equipment and a large variety of thermoplastic materials. Even so, issues are still to be solved regarding the adhesion mechanisms at the level of bond interface, especially for dissimilar materials. Therefore, this paper aimed to identify influencing factors over the printing process of multi-material parts at the interface level. The influencing factors were determined using a literature review and Cura slicing tool user guide and systematised using a cause-effect diagram. The main domains of influence are Materials bonding, Printing equipment, Model geometry, and Method of printing and processing. These domains were further split into more specific factors and discussed based on their influence over multi-material interface printing.

A new topology based feature extraction method for classification of interictal epileptiform discharges (IEDs) in EEG recordings from patients with epilepsy is proposed. After dimension reduction of the recorded EEG signal, using dynamical component analysis (DyCA) or principal component analysis (PCA), a persistent homology analysis of the resulting phase space trajectories is performed. Features are extracted from the persistent homology analysis and used to train and evaluate a support vector machine (SVM). Classification results based on these persistent features are compared with statistical features of the dimension-reduced signals and combinations of all of these features. Combining the persistent and statistical features improves the results (accuracy 94.7 %) compared to using only statistical feature extraction, whereas applying only persistent features does not achieve sufficient performance. For this classification example the choice of the dimension reduction technique does not significantly influence the classification performance of the algorithm.