Hydraulic Servo-systems

Mohieddine Jelali received the Dipl.-Ing. and Dr.-Ing. degrees from the University of Duisberg, Germany in 1993 and 1997 respectively, both in mechanical engineering. From 1993 to 1996, he was research assistant with the Department of Measurement and Control. From 1996 to 1999, he worked as a research-and-development engineer with Mannesmann Demag Metallurgy in Ratingen, BU Cold Rolling and Processing. In September 1999, he joined the Betriebsforchungsinstitut - VDEh-Institut für angewandte Forschung GmbH in Düsseldorf as a project manager and co-ordinator of multinational research projects in the steel industry. His main fields of interest include: modelling, dynamic simulation, development of advanced controls and control prototyping for rolling mills and supervisory control of steel processes. Since October he has been a lecturer in control systems at the University of Duisberg. He has written/co-written 14 research publications. Andreas Kroll obtained his Dr.-Ing. in mechanical engineering at the University of Duisberg in 1996. From 1993 to 1996, he was also a research assistant with the Department of Measurement and Control. In 1996 Doctor Kroll joined the ABB Research Centre in Heidelberg as a research-and-development engineer. Since 1998, he has been International R&D manager and since 2000, the group leader for Applied Control and Optimisation. His current research interests include: methods of computational intelligence, advanced process control and applications, dynamic simulation and optimisation of processes, international project management and personal and technological strategies of the line unit. He has written or co-written 16 publications.

1 Introduction.- 1.1 Historical View and Motivation for Hydraulic Systems.- 1.2 Aims and Focus of the Book.- 1.3 Outline of the Chapters.- 1.4 Background of the Work and Bibliographical Notes.- 2 General Description of Hydraulic Servo-systems.- 2.1 Basic Structure of Hydraulic Servo-systems.- 2.2 Description of the Components.- 2.3 Classification of Hydraulic Servo-systems.- 2.4 Measurement and Control Devices.- 2.5 Application Examples.- 3 Physical Fundamentals of Hydraulics.- 3.1 Physical Properties of Fluids.- 3.2 General Equations of Fluid Motion.- 3.3 Flow Through Passages.- 3.4 Spool Port Forces.- 3.5 Electro-hydraulic Analogy.- 4 Physically Based Modelling.- 4.1 Introduction.- 4.2 Elementary Models.- 4.3 Typical Non-linear State-space Models.- 4.4 Structured and Simplified Models of Valve-controlled Systems.- 4.5 Determination of Specific Model Parameters.- 4.6 Implementation and Software Tools.- 4.7 Section Summary.- 5 Experimental Modelling (Identification).- 5.1 Introduction.- 5.2 Pre-identification Process.- 5.3 Overview of Model Structures.- 5.4 Description of Selected Non-linear Model Structures.- 5.5 Parameter Estimation Methods.- 5.6 Optimisation Algorithms.- 5.7 Grey-box Identification ofNon-linear Hydraulic Servo-system Models.- 5.8 Fuzzy Identification.- 5.9 Identification with Artificial Neural Networks.- 6 Hydraulic Control Systems Design.- 6.1 Introduction.- 6.2 Classical Feedback Control Design.- 6.3 Estimator-based State Feedback Control.- 6.4 Extensions to Linear Feedback Control.- 6.5 Feedback Linearising Control.- 6.6 Approaches Similar to Feedback Linearisation.- 6.7 Fuzzy Control.- 6.8 Neural-network-based Control.- 6.9 Vibration Damping Control.- 6.10 State Estimation.- 6.11 Implementation and Software Tools.- 6.12 Rapid Prototyping Tools for Control.- 6.13 Section Summary.- 7 Case Studies and Experimental Results.- 7.1 Identification and Control of a Synchronising Cylinder.- 7.2 Modelling and Control of a Small Differential Cylinder.- 7.3 Control of a Big Differential Cylinder.- 7.4 Vibration Damping Control for a Flexible Robot.- 7.5 Vibration Damping Control for a Concrete Pump.- Appendix A Fluid Power Symbols.- Appendix B Data and Catalogue Sheets.- Appendix C Non-linear Control Background.- References.