07 Fakultät Konstruktions-, Produktions- und Fahrzeugtechnik
Permanent URI for this collectionhttps://elib.uni-stuttgart.de/handle/11682/8
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Item Open Access Robust Design Methodology for the development of commercial vehicle braking systems(2015) Kemmler, Stefan; Leopold, Tobias; Fricke, Jens; Bertsche, BerndToday’s product requirements demand an ever increasing functionality for the same space and usually the same number of components. Thereby, the quality, reliability and robustness of these products should be preserved or even be increased. This target conflict cannot be solved without compromises. The research community between the Institute of Machine Components (IMA), University of Stuttgart, and the Knorr-Bremse Systeme für Nutzfahrzeuge GmbH is seeking for new solutions for these challenges. The new approaches for designing robust and reliable products are being implemented directly in a current development project of an innovative Air Disc Brake (ADB). With “Systematic Method for Axiomatic Robustness-Testing” (SMART), reliability methods and the basic concept of Robust Design methodology are related to the Taguchi Method. SMART is based on three phases: System, Parameter and Tolerance Design; accordingly, the sample phases of VDA (Association of German Automotives) are used as milestones. In the System Design, SMART focuses on the decreasing complexity according to the functional dependences of the DPs, thus precluding early random failures. In the Parameter Design phase, SMART gives the developer an approach for modeling an adaptive simulation model (SIM-SMART). This model also enables the simulation of random and possible fatigue failures in addition to the nominally robust DPs. In the early stage of product development, reliability predictions are possible. In the iterative Tolerance Design phase, the final tolerance limits for robust and reliable products are defined with consideration of compromises in terms of costs, quality and technical feasibility. With the application of SMART, a design concept of a new generation of an ADB with less complexity is created. The extensive functions for flexible function studies are modeled with the objective of SIM-SMART. Accordingly to this model, parameter studies for determination of the nominal adjustment levels can be performed and their random and fatigue failures modeled. In conclusion, more accurate reliability test strategies are recommended using the definition of tolerance limits. The cost aspect and technical feasibility are also taken into account. So far, SMART has not been added to the iterative Tolerance Design phase. With this paper, the method is not only extended to this phase, but also sufficiently validated. In addition, SMART can predict and analyze random failures. With its three coherent and iterative phases, it is an as yet unpublished and unimplemented approach for designing even more robust and reliable products. Robust Design Methodology and reliability methods are fundamental building blocks for products with high quality requirements. SMART presents an approach to support the designing of robust, reliable, highly functional and innovative ADB.Item Open Access Chemical process control : present status and future needs ; the view from European industry(1991) Schuler, Hans; Allgöwer, Frank; Gilles, Ernst DieterNot only in Europe, chemical process control is characterized by a broad invasion of distributed control systems into chemical plants. The information integration from process control up to business management is a great challenge of today which follows from the overall computerization of production. Most of the recent progress in process automation results from the application of computer science paradigms to control systems, and of advanced developments in field instrumentation. Despite these advances and the considerable progress made in process control theory, there is only limited acceptance and application of modern advanced process control methodologies in industrial practice. This paper is an attempt to summarize the European discussion on the reasons for these facts.Item Open Access DAMOS-C ein neutrales Datenformat zur standardisierten Anbindung von MKS an Simulationssysteme mit offener Systemarchitektur(1994) Thomson, Bernd; Neerpasch, Uwe; Schiehlen, WernerDer Arbeitskreis "Simulation der Systemdynamik des Fahrzeuges in der deutschen Automobilindustrie" der Firmen AUDI, BMW, MB/DB, Porsche und VW hat ein Simulationskonzept mit weitgehend offener Systemarchitektur zur Behandlung dynamischer Vorgänge im Fahrzeug erarbeitet. Grundgedanke dabei war, ein flexibles und sehr allgemein für alle Fragestellungen im Bereich mechatronischer Systeme einsetzbares Simulationswerkzeug auf Basis voneinander unabhängiger, kommerziell verfügbarer Software-Bausteine zur rechnergestützten Modellbildung mechanischer, hydraulischer und elektronischer Teilsysteme standardmäßig verfügbar zu machen. Im vorliegenden Beitrag wird am Beispiel einer prototypischen Integration der MKS-Modellerstellungssoftware, auf Basis einer im OFG-5chwerpunktprogramm "Dynamik von Mehrkörpersystemen (MKS)" entwickelten Datenkapsel DAMOS-C, die grundlegende Funktionalität dieser Vorgehensweise vorgestellt.Item Open Access Robust reliability or reliable robustness? : integrated consideration of robustness- and reliability-aspects(2015) Kemmler, Stefan; Eifler, Tobias; Bertsche, Bernd; Howard, Thomas J.Commonly, the terms reliability and robustness are used to describe products and processes, which are in accordance with the customer requirements and fulfil high quality expectations. However, significant differences between the underlying definitions raise the questions how reliable robust products are and vice versa. For a comprehensive understanding and to use existing synergies between both domains, this paper discusses the basic principles of Reliability- and Robust Design theory. The development of a comprehensive model will enable an integrated consideration of both domains in the future, will offer guidance for a systematic choice of corresponding methods and is thus aiming to pave the way for future research.Item Open Access Dual-wavelength interferometer for surface profile(1990) Manhart, Sigmund; Maurer, R.; Tiziani, Hans J.; Sodnik, Zoran; Fischer, Edgar; Mariani, A.; Bonsignori, R.; Margheri, Giancarlo; Giunti, C.; Zatti, StefanoThe design and first experimental results of a dual-wavelength heterodyne interferometer (DWHI) for precise surface profile measurements are presented. The DWHI is based on a Mach-Zehnder type interferometer with the surface to be measured in the sensing arm of the interferometer. Two adjacent wavelengths are simultaneously used in the interferometer; the range information is gained from the beat frequency of both heterodyne interferometer signals. Thus, the extreme range ambiguity of classical interferometers and their sensitivity to mechanical distortions are reduced by the ratio of laser frequency to beat frequency. The DWHI is expected to have the good SIN performance a of coherent detection system but also the capability of measuring to diffusely scattering targets. The main features of the system presented here are: - use of a single diode laser in combination with a high frequency Bragg cell to generate two adjacent wavelengths - use of an all-fiber concept for the optomechanical build-upItem Open Access Dynamische Simulation verfahrenstechnischer Prozesse und Anlagen : ein Vergleich von Werkzeugen(1994) Watzdorf, Rüdiger von; Allgöwer, Frank; Helget, Andreas; Marquardt, Wolfgang; Gilles, Ernst DieterZusammenfassend zeigen unsere Erfahrungen, daß sich prinzipiell alle betrachteten Werkzeuge zur Simulation verfahrenstechnischer Prozesse und Anlagen eignen. Die Werkzeuge zeichnen sich allerdings durch eine unterschiedliche Zielrichtung aus: SlMULINK bietet einen sehr hohen Modellimplementierungs-, Verschaltungs- und Bedienkomfort; ACSL und SPEEDUP sind für die Modellierung und Implementierung neuer Modelle besonders geeignet, wobei SPEEDUP speziell die Bedürfnisse der Verfahrenstechnik unterstützt; DIVA ist weniger auf den Modellierer und mehr auf den Anwender ausgerichtet, der aus vorhandenen Bibliotheken Modelle auswählt, parametriert und verschaltet.Item Open Access Modellierung und Berechnung der Eigenschaften von Gleitführungen mit der Finite Elemente Methode(1990) Heisel, Uwe; Chlebus, EdwardBei der Berechnung von Maschinenkomponenten mit Hilfe der Finite-Elemente-Methode stellt die Modellierung der Kontaktstellen zwischen den einzelnen Maschinenteilen ein Problem dar. Durch die Nichtlinearitäten der Fügestellen konnten bisher bei der Berechnung von Flach-Gleitführungen keine zufriedenstellenden Ergebnisse erzielt werden. In diesem Beitrag wird gezeigt, wie die nichtlineare Charakteristik der Kontaktzonen mit Hilfe von Stabelementen modelliert werden kann. Durch Iteration wird die tatsächliche Form und Größe der Kontaktfläche ermittelt und daraus die auftretenden Flächenpressungen und Verformungen bestimmt.