OPTIMAL MODE SWITCHING FOR A HYDRAULIC ACTUATOR CONTROLLED WITH FOUR-VALVE INDEPENDENT METERING CONFIGURATION

Authors

  • Amir Shenouda Georgia Institute of Technology, Woodruff School of Mechanical Engineering, 801 Ferst Dr. NW, Atlanta, GA, 30332, USA
  • Wayne Book Georgia Institute of Technology, Woodruff School of Mechanical Engineering, 801 Ferst Dr. NW, Atlanta, GA, 30332, USA

Keywords:

hydraulics, independent metering valves, metering modes, mode capability curve, mode switching

Abstract

A spool valve is a single degree of freedom system that has coupled ‘meter in’ and ‘meter out’. Decoupling of meter in from meter out provides for more controllability and potential for energy saving in overrunning load cases when compared with a conventional spool valve controlled hydraulic system. A four-valve configuration controlling a hydraulic cylinder is emphasized in this paper. The four-valve configuration can operate in several two-valve discrete modes because each of the four valves is controlled separately from the others. Five distinct (or discrete) metering modes that exist in the literature are initially studied: Powered Extension, High Side Regeneration Extension, Low Side Regeneration Extension, Powered Retraction, and Low Side Regeneration retraction. Each of these modes has different force and speed capabilities and the operating mode should consequently be selected based on the load and the commanded speed. Proper switching between these modes is crucial for efficient and productive performance.

The problem of switching between these five modes is treated as an optimal control problem of a switched dynamic system. General theory for the optimal control problem is derived and then applied to the hydraulic system of interest. The results are then interpreted and explained by looking into the force-speed capability of modes, and a closed form solution for the quasi static case is presented.

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Author Biographies

Amir Shenouda, Georgia Institute of Technology, Woodruff School of Mechanical Engineering, 801 Ferst Dr. NW, Atlanta, GA, 30332, USA

Amir Shenouda Amir Shenouda received his Bachelor of Science in Mechanical engineering from The American University in Cairo in 1999. He received his Master of Science in Mechanical Engineering from Gannon University in 2002. He obtained a Masters of Science in Electrical Engineering and a Ph.D. in Mechanical Engineering from the Georgia Institute of Technology in 2006. His research focused on hydraulic control systems and specifically the four-valve independent metering configuration. Industrial experience includes Mercedes Benz, Bristol Myers, General Electric, HUSCO International, and Parker Hannifin.

Wayne Book, Georgia Institute of Technology, Woodruff School of Mechanical Engineering, 801 Ferst Dr. NW, Atlanta, GA, 30332, USA

Wayne Book Wayne J. Book received his B.S.M.E. degree from the University of Texas at Austin in 1969 and the M.S. and Ph.D. degrees in mechanical engineering from the Massachusetts Institute of Technology in 1971 and 1974, respectively. Wayne Book has been on the faculty of Mechanical Engineering at the Georgia Institute of Technology since 1974 where he is a Professor and the HUSCO/Ramirez Distinguished Professor in Fluid Power and Motion Control. His research includes the design, dynamics and control of high speed, lightweight motion systems, robotics, fluid power and motion control and haptics. He is a Fellow of the ASME, SME, and IEEE, and received Georgia Tech’s award for Outstanding Faculty Leadership for development of Graduate Research Assistants in 1987, and an ASME Dedicated Service Award in 2003 and the ASME DSCD Leadership Award in 2004.

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Published

2008-03-01

How to Cite

Shenouda, A., & Book, W. (2008). OPTIMAL MODE SWITCHING FOR A HYDRAULIC ACTUATOR CONTROLLED WITH FOUR-VALVE INDEPENDENT METERING CONFIGURATION. International Journal of Fluid Power, 9(1), 35–43. Retrieved from https://journals.riverpublishers.com/index.php/IJFP/article/view/531

Issue

2008: Vol 09 Iss 1

Section

Original Article

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