In this paper, a nonlinear position tracking controller is derived based on feedback linearization to globally linearize the nonlinear dynamics of an electrohydraulic actuator with nonlinear state feedback. A detailed computer model is developed for a four-post road simulation system with a transit bus as the test vehicle. Using this model, comparisons are conducted between the proposed nonlinear decentralized controller and a traditional linear decentralized controller. Previously introduced interaction measures suitable for time domain analysis of nonlinear systems confirm that, for the test vehicle considered, load plate position loop interactions are quickly eliminated by either the linear or nonlinear decentralized position controllers. The performance of the road simulator as gauged by a position tracking error metric for a typical rough road profile is improved by over 60% across all actuators and response matching of sprung mass vertical acceleration PSD is likewise improved by over 50% when using the nonlinear decentralized controller.

1.
Soderling, S., Sharp, M., and Leser, C., 1999, “Servo-Controller Compensation Methods: Selection of the Correct Techniques for Test Applications,” in VIII International Mobility Technology Conference and Exhibit, SAE, 1999-01-3000, Sao Paulo, Brazil, Oct 4–6.
2.
De Cuyper
Joris
,
Verhaegen
Michel
, and
Swevers
Jan
,
2003
, “
Off-Line Feed-Forward and H, Feedback Control on a Vibration Rig
,”
Control Engineering Practice
, Vol.
11
, pp.
129
140
.
3.
Ayalew, Beshahwired, 2005, “Nonlinear Control of Multi-Actuator Electrohydraulic Systems Based on Feedback Linearization with Application to Road Simulation,” Ph D Dissertation, in Mechanical Engineering, The Pennsylvania State University.
4.
de Pont
J.
,
1993
, “
Rating Heavy Vehicle Suspensions for ‘road friendliness’
,”
Heavy Vehicle Systems, Special Series, Int. J. of Vehicle Design
, Vol.
1
(
1
), pp.
20
33
.
5.
Slotine, Jean-Jacques E., and Li, Wieping, 1991, Applied Nonlinear Control. Prentice Hall.
6.
Khalil, Hassan K., 2002, Nonlinear Systems, Third ed., Prentice Hall.
7.
Axelson, Steve, and Kumar, K. S. P., 1988, “Dynamic Feedback Linearization of a Hydraulic Valve-Actuator Combination,” in the 1988 American Control Conference, Atlanta, Georgia, June 15–17, 1988.
8.
Hahn, H., Piepenbrink, A., and Leimbach, K.-D., 1994, “Input/Output Linearization Control of an Electro Servo-Hydraulic Actuator,” in the Third IEEE Conference on Control Applications, pp. 995–1000, Glasgow, UK.
9.
Vossoughi
Gholamreza
and
Donath
Max
,
1995
, “
Dynamic Feedback Linearization for Electrohydraulically Actuated Control Systems
,”
Journal of Dynamic Systems, Measurement, and Control
, Vol.
117
, pp.
468
477
, December 1995.
10.
Del Re
Luigi
, and
Isidori
Alberto
, 1995, “
Performance Enhancement of Nonlinear Drives by Feedback Linearization of Linear-Bilinear Cascade Models
,”
IEEE Transactions on Controls Systems Technology
, Vol.
3
(
3
), pp.
299
308
, September
1995
.
11.
Dransfield, Peter, 1981, Hydraulic Control Systems: Design and Analysis of their Dynamics. Springer-Verlag.
12.
Merritt, Herbert E., 1967, Hydraulic Control Systems. John Wiley and Sons, New York.
13.
Van Schothorst, Gerard, 1997, “Modelling of Long-Stroke Hydraulic Servo-Systems for Flight Simulator Motion Control and System Design,” PhD Thesis, Delft University of Technology, the Netherlands.
14.
Kugi, Andreas, 2001, Non-linear Control Based on Physical Models. Springer, London.
15.
Jelali, Mohieddine, and Kroll, Andreas, 2003, Hydraulic Servo-Systems: Modelling, Identification and Control. - (Advances in Industrial Control). Springer-Verlag, London.
16.
Ayalew, Beshahwired, and Kulakowski, Bohdan T., 2005, “Modeling Supply and Return Line Dynamics for an Electrohydraulic Actuation System,” ISA Transactions, Vol. 44(2), April 2005.
17.
Genta, Giancarlo, 1997, Motor Vehicle Dynamics: Modeling and Simulation. World Scientific Publishing Co., River Edge, New Jersey.
18.
Nova Bus Inc., Transit Bus Division, 2002, “Low Floor Bus Dimensions and Air Suspension Specifications,” David Klinikowski.
19.
Xiao, Jie, 2002, “System Identificatin for Transit Buses Using a Hybrid Genetic Algorithm,” PhD Thesis, in Mechanical Engineering, The Pennsylvania State University, University Park.
20.
Zhang, J., Xinglong, Y., Yi, L., Wangyu, W., Lingzhang, M., Yu, F., and Lin, W., 2002, “Performance Simulation Research on Bus with Air Suspension,” 2002-01–3093, SAE.
21.
Bristol
Edgar H.
,
1966
, “
On a New Measure of Interaction for Multivariable Process Control
,”
IEEE Transactions on Automatic Control
, Vol.
11
(
1
), pp.
133
134
, January 1966.
22.
Ramachandran
S.
and
Dransfield
P.
,
1993
, “
Interaction between the Actuators in Loaded Multi-Channel Electrohydraulic Drives
,”
Transactions of ASME, Journal of Dynamic Systems, Measurement and Control
, Vol.
115
, pp.
291
302
, June 1993.
23.
Skogestad, Sigurd and Postelthwaite, Ian, 1996, Multivariable Feedback Control. John Wiley & Sons, Chichester, United Kingdom.
24.
Witcher
M. F.
, and
McAvoy
T. J.
,
1977
, “
Interacting Control Systems: Steady State and Dynamic Measurement of Interaction
,”
ISA Transactions
, Vol.
16
(
3
), pp.
35
41
.
25.
Ayalew, Beshahwired and Kulakowski, Bohdan T., 2005, “Decentralized Control of Interacting Electrohydraulic Actuators in Road Simulation,” Int. Journal of Heavy Vehicle Systems, Vol. 13(4).
26.
Brauer, Matthew, 2000, “Control Algorithms for a Road Simulator in Durability Testing of Transit Buses,” Masters Thesis, The Pennsylvania State University, University Park, May 2000.
27.
UMTRI, 2005, “International Roughness Index (IRI),” University of Michigan Transportation Research Institute, http://www.umtri.umich.edu/erd/roughness/index.html
This content is only available via PDF.
You do not currently have access to this content.