Global ETD Search

201	Řízení jednoúčelového obráběcího stroje / Control of special purpose machine tool Plocek, Jaroslav January 2015 (has links) The master thesis treats the design of control system of special purpose machine tool. The first part analyzes and compares two possible variants of control system which use either a CNC control system Sinumerik or motion control system Simotion. Only the variant with the Simotion control system is subsequently examined in detail: its hardware configuration, the selection of components and partly also the software solution. The thesis further deals with the safety of the realized control system and of the whole machine. There are described general safety requirements of machinery based on harmonized European standards and their specific application in the design of safety functions and the safety circuits of solved machine tool.
202	Einsatz der Mechanismensoftware MechDev in der Lehre Hüsing, Mathias, Knobloch, Thomas, Brünjes, Vincent, Corves, Burkhard 20 June 2024 (has links) Die am Institut für Getriebetechnik, Maschinendynamik und Robotik (IGMR) der RWTH Aachen entstandene Software Mechanism Developer (MechDev) wurde mit dem Ziel entwickelt, ein umfangreiches aber dennoch intuitiv zu bedienendes Tool zur Analyse und Synthese ebener Mechanismen für Industrie, Lehre und Forschung zur Verfügung zu stellen. [1,2] Algorithmik, Softwareentwurf und aktueller Funktionsumfang der Software wurden in der Vergangenheit bereits ausgiebig vorgestellt [3,4]. Mit dem anstehenden Release der Software soll diese auch in den Lehrealltag des IGMR integriert werden. Zu diesem Zweck müssen die Inhalte der Veranstaltungen Elektromechanische Antriebstechnik und Bewegungstechnik auf die Software und deren Funktionen angepasst werden. Bis zuletzt wurde in beiden Veranstaltungen das Tool GeoGebra [5] zum einen für Visualisierungen von Sachverhalten in der Vorlesung genutzt, zum anderen dessen Verwendung den Studierenden in Laborveranstaltungen vermittelt, um eigenständig Problemstellungen der Getriebetechnik damit zu bearbeiten. In diesem Beitrag sollen erste Ideen zum Einsatz der Software MechDev in der Lehre am IGMR vorgestellt werden. Beispielhaft soll eine passende Übungsaufgabe gezeigt werden, sowie deren Bearbeitung mit MechDev. Weiterhin werden zusätzliche Funktionen abgeleitet, die zukünftig für die Nutzung der Software in der Lehre implementiert werden sollen. / The Software Mechanism Developer (MechDev), which was developed at the Institute of Mechanism Theory, Machine Dynamics and Robotics (IGMR) at RWTH Aachen University, was developed with the aim of providing a comprehensive yet intuitive tool for analysing and synthesising planar mechanisms for industry, teaching and research. [1,2] The algorithms, software design and current functional scope of the software have already been extensively presented in the past [3,4]. With the upcoming release of the software, it is also to be integrated into everyday teaching at the IGMR. To this end, the content of the Electromechanical Drive Technology and Motion Technology courses must be adapted to the software and its functions. Until recently, the GeoGebra [5] tool was used in both courses to visualise facts in the lecture, and students were also taught how to use it in laboratory courses in order to work independently on transmission technology problems. This article will present initial ideas for using the MechDev software in teaching at the IGMR. A suitable exercise will be shown as an example, as well as how it can be worked on with MechDev. Furthermore, additional functions will be derived that are to be implemented in the future for the use of the software in teaching. info:eu-repo/classification/ddc/620 ddc:620 info:eu-repo/classification/ddc/600 ddc:600
203	Settling-Time Improvements in Positioning Machines Subject to Nonlinear Friction Using Adaptive Impulse Control Hakala, Tim 31 January 2006 (has links) (PDF) A new method of adaptive impulse control is developed to precisely and quickly control the position of machine components subject to friction. Friction dominates the forces affecting fine positioning dynamics. Friction can depend on payload, velocity, step size, path, initial position, temperature, and other variables. Control problems such as steady-state error and limit cycles often arise when applying conventional control techniques to the position control problem. Studies in the last few decades have shown that impulsive control can produce repeatable displacements as small as ten nanometers without limit cycles or steady-state error in machines subject to dry sliding friction. These displacements are achieved through the application of short duration, high intensity pulses. The relationship between pulse duration and displacement is seldom a simple function. The most dependable practical methods for control are self-tuning; they learn from online experience by adapting an internal control parameter until precise position control is achieved. To date, the best known adaptive pulse control methods adapt a single control parameter. While effective, the single parameter methods suffer from sub-optimal settling times and poor parameter convergence. To improve performance while maintaining the capacity for ultimate precision, a new control method referred to as Adaptive Impulse Control (AIC) has been developed. To better fit the nonlinear relationship between pulses and displacements, AIC adaptively tunes a set of parameters. Each parameter affects a different range of displacements. Online updates depend on the residual control error following each pulse, an estimate of pulse sensitivity, and a learning gain. After an update is calculated, it is distributed among the parameters that were used to calculate the most recent pulse. As the stored relationship converges to the actual relationship of the machine, pulses become more accurate and fewer pulses are needed to reach each desired destination. When fewer pulses are needed, settling time improves and efficiency increases. AIC is experimentally compared to conventional PID control and other adaptive pulse control methods on a rotary system with a position measurement resolution of 16000 encoder counts per revolution of the load wheel. The friction in the test system is nonlinear and irregular with a position dependent break-away torque that varies by a factor of more than 1.8 to 1. AIC is shown to improve settling times by as much as a factor of two when compared to other adaptive pulse control methods while maintaining precise control tolerances. control position adaptive impulsive settling-time nonlinear friction pulses displacements precise tolerances log-spaced update distributed learning Coulomb Stribeck Tomizuka Yang AIC PID MRAC STR RTAI Linux FreeBSD kernel modules microcontroller convergence practical self-tuning methods techniques limit-cycles steady-state error zero stable stability bound envelope partitioned scheme lookup-table multi-point adaptation repeatable mean servo motor exponential square-law rise-time real-time log-log interpolation pro-forma curve-fit sensitivity compliance variable static dynamic response torque acceleration velocity optical encoder parameters evolution fixed-law enhanced split weighting initialization trajectory layered processes Mechanical Engineering

Page generated in 0.0299 seconds