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 Beurteilung von Oberflächen durch Prozeßsimulation(1992) Heisel, Uwe; Fischer, Andreas; Maier, VolkerDie Oberflächenqualität wird durch das dynamische Verhalten der Maschine beim Umfangsplanfräsen wesentlich beeinflußt. Beim Fräsvorgang entstehen durch den Zahneingriff auf der Werkstückoberfläche Zykloidenbewegungen in Form von spitzen Wellenbergen und runden Wellentälern. Zur Beurteilung von Oberflächen wurde ein Softwarepaket entwickelt, mit dem sowohl der kinematisch reine Prozeß als auch der durch das dynamische Verhalten der Maschine gestörte Prozeß, dargestellt werden kann. Durch Definition einer Kennzahl für die Ungleichmäßigkeit der Rillenabfolge können mit diesem Instrumentarium verschiedene Prozesse bzw. deren Störungen in ihrer Auswirkung auf die Oberflächenqualität verglichen werden. Am Institut für Werkzeugmaschinen der Universität Stuttgart werden mit Betriebsschwingungs- und Modalanalysen, Konstruktionsänderungen auch im Hinblick auf Oberflächenqualität in der Holzbearbeitung durchgeführt. In einer dreiteiligen Serie zur Oberflächenqualität beim Umfangsplanfräsen werden die Möglichkeiten beschrieben, die aus der Auswertung von Oberflächenprofilen zur Maschinenoptimierung entstehen.Item Open Access Analyzing and optimizing multibody systems(1992) Bestle, Dieter; Eberhard, PeterOptimization of holonomic as well as non-holonomic multibody systems is presented as a nonlinear programming problem that can be solved with general-purpose optimization codes. The adjoint variable approach is used for calculating design derivatives of a rather general integral type performance measure with respect to design parameters. The resulting equations are solved by numerical integration backward in time. A multi-step integration algorithm with order and step-size control is adapted for this application by including an interpolation scheme. Numerical experiments and a comparison to the common approach of approximating the gradient of the performance measure by finite differences show that high efficiency, accuracy, and reliability are achievable.Item Open Access Prospects of the German multibody system research project on vehicle dynamics simulation(1992) Schiehlen, WernerThe German Research Council (DFG) decided 1987 to establish a nationwide research project devoted to dynamics of multibody systems. In this project 14 universities and research centers are cooperating with the goal to develop a general purpose multibody system software package. This concept provides the opportunity to use a modular structure of the software, i.e. different multibody formalisms may be combined with different simulation programmes via standardized interfaces. For the DFG project the database RSYST was chosen using standard FORTRAN 77 and an object oriented multibody system datamodel was defined. According to the modular concept the requirements of vehicle system dynamics as tire models or railway wheel-rail models, respectively, are easily met. The Iltis benchmark problem is used to demonstrate some features of the object oriented datamodel.Item Open Access Item Open Access FFS auf dem Prüfstand : Praxis-Untersuchung: Wie zuverlässig sind flexible Fertigungssysteme?(1992) Heisel, UweGegenstand der Untersuchung waren Flexible Fertigunssysteme (FFS) vom Berliner Werkzeugmaschinen-Hersteller Fritz Wemer. Die Einflußgrößen und deren Gewichtung auf den effektiven Nutzungsgrad von FFS wurden bei 14 Anwendem untersucht, wobei festzuhalten ist, daß die FFS entsprechend den Anforderungen der unterschiedlichen Anwender konfiguriert wurden. Die Branchen Maschinenbau, Werkzeugmaschinen und Textilmaschinenbau waren ebenso vertreten wie Druck- und Sondermaschinenbau. Relevante Daten für die Auswertung konnten bei 13 Unternehmen ermittelt werden.Item Open Access A novel approach to determine decorrelation effect in a dual-beam electronic speckle pattern interferometer(1992) Peng, Xiang; Diao, Hongyan; Zou, Yunlu; Tiziani, Hans J.An intrinsic decorrelation effect in a dual-beam ESPI system for contouring application is quantified by simple image processing techniques incorporating experimental data of speckle patterns. Practical limits for the range of application on contouring an object are also considered from the point of view of automatic fringe analysis. An acceptable degree of decorrelation due to the tilt of illuminating beams has been established.Item Open Access Contouring by electronic speckle pattern interferometry with quadruple-beam illumination(1992) Zou, Yunlu; Diao, Hongyan; Peng, Xiang; Tiziani, Hans J.We present a new arrangement for contouring by electronic speckle pattern interferometry with four illumination beams, thereby making it unnecessary to move anything during the measurement.Item Open Access Production of structured thin wooden chips by milling with small cutting angles(1994) Heisel, Uwe; Tröger, JohannesThin wooden chips can be used in a wide range, primarily to produce ecological positive materials to substitute plastics and mineral wool for the use of thermal isolation and packaging materials. There are wide resources of wood and it can be wasted ecologically. Additionally, the production of wooden chips for the above mentioned purposes has clear advantages regarding the expenditure of energy. With existing machining methods for the production of wooden cutting chips, only a chip thickness of more than .25 mm can be realized. Bya new machining method with small tool rake angles, proper extremely thin and folded (structured) chips can be generated. The research emphasis is to study the parameters for generating these chips and their properties for thermal isolation and packaging purposes. First positive results show that this material can be the basis for a new wood material with an isolation property very closed to styrofoam (PS).Item Open Access High precision optical surface topometry(1993) Tiziani, Hans J.For contactless measurement of the surface topography optical techniques are promissing. A lot of progress was made by the development of laser supported methods. It is due to the development of new different lasers, the introduction of solid state detectors and powerful computers for the information processing. Time of flight, phase measurements, active and passive triangulation and projected fringes are very robust techniques for industrial applications. A lot of progress was made in the application of interferometry to surface and vibration measurements. One or more wavelength together with diode lasers are used. Although interferometry requires polished surfaces, however, by using synthetic wavlengths, it can also be applied for optically rougher surfaces. In addition the unambiguity range will be extended when longer synthetic wavelengths are used. Furthermore scanning and whole field confocal microscopy can be used for macro- and microstructure analysis. New techniques will be described to extend the field of view. Some limits especially with respect to resolution and industrial application will be discussed for the methods presented together with some experimental results and future developments.Item Open Access Process integrity of deep hole drilling for small diameters(1993) Heisel, Uwe; Eichler, RalfProcess-integrity in deep-hole drilling with solid-tungsten-carbide-drills of 1 and 2 millimeter diameter requires chipremoval in the bead by the internal cutting-fluid supply. The flow rate of the cutting fluid depends on the internal profile and the length of the drill-shaft· The cross-sectional area of the shaft also determines its stiffness and breaking strength. Tool wear increases the cutting forces and thereby also the stressing of the drill. Optimisation of the progress-integrity can be achieved by careful selection of the cutting-parameters.