Download or read book Position flexible Modeling Approach for an Efficient Optimization of the Machine Tool Dynamics Considering Local Damping Effects written by Thomas Semm and published by utzverlag GmbH. This book was released on 2021-03-31 with total page 134 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Condition Monitoring of Machine Tool Feed Drives and Methods for the Estimation of Remaining Useful Life written by Maximilian Johann Florian Benker and published by utzverlag GmbH. This book was released on 2024-01-31 with total page 170 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book A holistic model predictive process control for plastic metal direct joining written by Stefan P. Meyer and published by utzverlag GmbH. This book was released on with total page 170 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Technology Strategy for Metal based Additive Manufacturing written by Marc Matthias Schneck and published by utzverlag GmbH. This book was released on 2022-01-14 with total page 228 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Laser Structuring of Graphite Anodes for Functionally Enhanced Lithium Ion Batteries written by Jan Bernd Habedank and published by utzverlag GmbH. This book was released on 2022-01-21 with total page 204 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Applied Mechanics Reviews written by and published by . This book was released on 1988 with total page 384 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Dynamic Model Identification and Trajectory Correction for Virtual Process Planning in Multi axis Machine Tools written by Mustafa Hakan Turhan and published by . This book was released on 2019 with total page 120 pages. Available in PDF, EPUB and Kindle. Book excerpt: In today's industry, the capability to effectively reduce production time and cost gives a manufacturer a vital advantage against its competitors. Specifically, in the machining industry, the ability to simulate the dynamic performance of machine tools, and the physics of cutting processes, is critical to taking corrective actions, achieving process and productivity improvements, thereby enhancing competitiveness. In this context, being able to estimate mathematical models which describe the dynamic response of machine tools to commanded tool trajectories and external disturbance forces plays a key role in establishing virtual and intelligent manufacturing capability. These models can also be used in virtual simulations for process improvement, such as compensating for dynamic positioning errors by making small corrections to the commanded trajectory. This, in turn, can facilitate further productivity improvement and part quality in multi-axis manufacturing operations, such as machining. This thesis presents new methods for identifying the positioning response and friction characteristics of machine tool servo drives in a nonintrusive manner, and an approach for enhancing dynamic positioning accuracy through commanded trajectory correction via Iterative Learning Control (ILC). As the first contribution, the linear transfer functions correlating the positioning response to the commanded trajectory and friction disturbance inputs are identified using a new pole search method in conjunction with least squares (LS) projection. It is validated that this approach can work with in-process collected data, and demonstrates superior convergence and numerical characteristics, and model prediction accuracy, compared to an earlier 'rapid identification' approach based on the application of classical Least Squares for the full model. Effectiveness of the new method is demonstrated in simulations, and in experimental case studies for planar motion on two different machine tools, a gear grinding machine and a 5-axis machining center. Compared to the earlier approach, which could predict servo errors with 10-68% closeness, the new method improves the prediction accuracy to 0.5-2%. In the simulation of feed drives used in multi-axis machines, high fidelity prediction of the nonlinear stick-slip friction plays an important role. Specifically, time-dependent (i.e., dynamic) friction models help to improve the accuracy of virtual predictions. While many elaborate models have been proposed for this purpose, such as the generalized Maxwell-slip (GMS) model, their parameters can be numerous and difficult to identify from limited field data. In this thesis, as the second contribution, a new and highly efficient method of parameterizing the pre-sliding (hysteretic) portion of the GMS friction model is presented. This approach drastically reduces the number of unknown variables to identify, by estimating only the affective breakaway force, breakaway displacement, and 'shape factor' describing the shape of the pre-sliding virgin curve. Reduction in the number of unknowns enables this 'reduced parameter' GMS model to be identified much more easily from in-process data, compared to the fully parameterized GMS model, and the time-dependent friction dynamics can still be simulated accurately. Having improved the positioning response transfer function estimation and friction modeling, as the third contribution of this thesis, these two elements are combined together in a 3-step process. First, the servo response is estimated considering simplified Coulomb friction dynamics. Then, the friction model is replaced and identified as a reduced parameter GMS model. In the third step, the transfer function poles and zeros, and the reduced parameter GMS model, are concurrently optimized to replicate the observed experimental response with even greater fidelity. This improvement has been quantified as 12-44% in RMS and 28-54% in MAX values. This approach is successful in servo systems with predominantly rigid body behavior. However, its extension to a servo system with vibratory dynamics did not produce an immediately observed improvement. This is attributed to the dominance of vibrations in response to the commanded trajectory, and further investigation is recommended for future research. Having an accurate model of a multi-axis machine's feed drive response allows for the dynamic positioning errors, which can lead to workpiece inaccuracy or defects, to be predicted and corrected ahead of time. For this purpose, ILC has been investigated. It is shown that through ILC, 1-2 orders of magnitude reduction in the servo errors is possible. While ILC is already available in certain commercial CNC systems, its training cycle (which is performed during the operation of the machine tool) can lead to part defects and wasted productive machining time. The new idea proposed in this thesis is to perform ILC on a virtual model, which is continuously updated via real-time production data using the identification methods developed in this work. This would minimize the amount of trial and error correction needed on the actual machine. In the course of this thesis research, after validating the effectiveness of ILC in simulations, to reliably and safely migrate the virtual modeling and trajectory correction results into industry (such as on a gear grinding machine tool), the author initiated and led the design and fabrication of an industry-scale testing platform, comprising a Siemens 840D SolutionLine CNC with a multi-axis feed drive setup. Majority of this implementation has been completed, and in near future work, the dynamic accuracy and productivity improvements facilitated with 'virtually' tuned ILC are expected to be demonstrated experimentally and tested in industry.

Download or read book Machine Tool Vibrations and Cutting Dynamics written by Brandon C Gegg and published by Springer. This book was released on 2011-05-01 with total page 188 pages. Available in PDF, EPUB and Kindle. Book excerpt: Exploring the fundamentals of cutting dynamics from the perspective of discontinuous systems theory, this volume shows how to use coupling, interaction, and different cutting states to mitigate machining instability and enable better machine tool design.

Download or read book Dissertation Abstracts International written by and published by . This book was released on 1995 with total page 770 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Machine Tool Structures written by F. Koenigsberger and published by Elsevier. This book was released on 2016-01-21 with total page 528 pages. Available in PDF, EPUB and Kindle. Book excerpt: Machine Tool Structures, Volume 1 deals with fundamental theories and calculation methods for machine tool structures. Experimental investigations into stiffness are discussed, along with the application of the results to the design of machine tool structures. Topics covered range from static and dynamic stiffness to chatter in metal cutting, stability in machine tools, and deformations of machine tool structures. This volume is divided into three sections and opens with a discussion on stiffness specifications and the effect of stiffness on the behavior of the machine under forced vibration conditions. The following chapters explore the stability of the machine structure against chatter; methods of stability analysis; tests and principles of dampers; chatter during grinding operations; and stresses and deformations of closed box structures subjected to bending and shear. Calculation methods for determining stiffness constants of a structure's individual parts, as well as methods for determining the resulting stiffnesses, modal shapes, and their parameters, are also described. The final chapter presents systematic procedures for the analysis of machine tool structures. This book is intended for university students, research workers, and designers.

Download or read book Twin Control written by Mikel Armendia and published by Springer. This book was released on 2019-01-05 with total page 296 pages. Available in PDF, EPUB and Kindle. Book excerpt: This open access book summarizes the results of the European research project “Twin-model based virtual manufacturing for machine tool-process simulation and control” (Twin-Control). The first part reviews the applications of ICTs in machine tools and manufacturing, from a scientific and industrial point of view, and introduces the Twin-Control approach, while Part 2 discusses the development of a digital twin of machine tools. The third part addresses the monitoring and data management infrastructure of machines and manufacturing processes and numerous applications of energy monitoring. Part 4 then highlights various features developed in the project by combining the developments covered in Parts 3 and 4 to control the manufacturing processes applying the so-called CPSs. Lastly, Part 5 presents a complete validation of Twin-Control features in two key industrial sectors: aerospace and automotive. The book offers a representative overview of the latest trends in the manufacturing industry, with a focus on machine tools.

Download or read book Government Reports Announcements Index written by and published by . This book was released on 1991 with total page 628 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Power System Dynamics and Stability written by Peter W. Sauer and published by . This book was released on 1998 with total page 376 pages. Available in PDF, EPUB and Kindle. Book excerpt: For a one-semester senior or beginning graduate level course in power system dynamics. This text begins with the fundamental laws for basic devices and systems in a mathematical modeling context. It includes systematic derivations of standard synchronous machine models with their fundamental controls. These individual models are interconnected for system analysis and simulation. Singular perturbation is used to derive and explain reduced-order models.

Download or read book Index to Theses with Abstracts Accepted for Higher Degrees by the Universities of Great Britain and Ireland and the Council for National Academic Awards written by and published by . This book was released on 2007 with total page 360 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Recent Advances and Applications of Hybrid Simulation written by Wei Song and published by Frontiers Media SA. This book was released on 2021-01-13 with total page 213 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Feedback Systems written by Karl Johan Åström and published by Princeton University Press. This book was released on 2021-02-02 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: The essential introduction to the principles and applications of feedback systems—now fully revised and expanded This textbook covers the mathematics needed to model, analyze, and design feedback systems. Now more user-friendly than ever, this revised and expanded edition of Feedback Systems is a one-volume resource for students and researchers in mathematics and engineering. It has applications across a range of disciplines that utilize feedback in physical, biological, information, and economic systems. Karl Åström and Richard Murray use techniques from physics, computer science, and operations research to introduce control-oriented modeling. They begin with state space tools for analysis and design, including stability of solutions, Lyapunov functions, reachability, state feedback observability, and estimators. The matrix exponential plays a central role in the analysis of linear control systems, allowing a concise development of many of the key concepts for this class of models. Åström and Murray then develop and explain tools in the frequency domain, including transfer functions, Nyquist analysis, PID control, frequency domain design, and robustness. Features a new chapter on design principles and tools, illustrating the types of problems that can be solved using feedback Includes a new chapter on fundamental limits and new material on the Routh-Hurwitz criterion and root locus plots Provides exercises at the end of every chapter Comes with an electronic solutions manual An ideal textbook for undergraduate and graduate students Indispensable for researchers seeking a self-contained resource on control theory

Download or read book Introduction to Aircraft Flight Mechanics written by Thomas R. Yechout and published by AIAA. This book was released on 2003 with total page 666 pages. Available in PDF, EPUB and Kindle. Book excerpt: Based on a 15-year successful approach to teaching aircraft flight mechanics at the US Air Force Academy, this text explains the concepts and derivations of equations for aircraft flight mechanics. It covers aircraft performance, static stability, aircraft dynamics stability and feedback control.