A new variable structure control strategy consists of two separate sliding mode controllers (SMCs) with a switching mechanism designed to address position tracking problem of electro-hydraulic servo systems (EHS) with acceleration constraint, which can be found in numerous mechatronics and industrial control system applications. Examples include fatigue testing systems, plate hot rolling systems, injection molding machines, hydraulic elevators, and robotic arms. In this paper, first, a complete model of an electro-hydraulic system is proposed in which detailed mathematical descriptions for all elements are included. Not only is a more accurate model capable of providing a fertile ground for simulation studies but also it could contribute toward better results in the control approach. Furthermore, based on the variable dynamic behavior of EHS in forward and return motions, two separate SMCs synchronizing with a switching mechanism are applied. This novel approach calculates two separate control input in each instance for each dynamic behavior of the system and the switching mechanism decides which one should utilize. It is shown that the proposed control method, despite model uncertainties and external disturbances, tracks the reference position with error in scale of 10−3, and its remarkable accuracy in tracking trajectories with acceleration constraint, which has a great deal of importance in the sense of many industrial applications, is proved.

References

1.
Jelali
,
M.
, and
Kroll
,
A.
,
2003
,
Hydraulic Servo-Systems Modelling, Identification and Control
,
Springer-Verlag
,
London
.
2.
Merrit
,
H. E.
,
1967
,
Hydraulic Control System
,
Wiley
,
New York
.
3.
Wu
,
M. C.
, and
Shih
,
M. C.
,
2003
, “
Simulated and Experimental Study of Hydraulic Anti-Lock Braking System Using Sliding-Mode PWM Control
,”
Mechatronics
,
13
(
4
), pp.
331
351
.
4.
Rena
,
Y.
, and
Ruan
,
J.
,
2016
, “
Theoretical and Experimental Investigations of Vibration Waveforms Excited by an Electro-Hydraulic Type Exciter for Fatigue With a Two-Dimensional Rotary Valve
,”
Mechatronics
,
33
, pp.
161
172
.
5.
Songshan
,
H.
,
Zongxia
,
J.
,
Chengwen
,
W.
, and
Yaoxing
,
S.
,
2015
, “
Fuzzy Robust Nonlinear Control Approach for Electro-Hydraulic Flight Motion Simulator
,”
Chin. J. Aeronaut.
,
28
(
1
), pp.
294
304
.
6.
Kim
,
M. Y.
, and
Lee
,
C.-O.
,
2006
, “
An Experimental Study on the Optimization of Controller Gains for an Electro-Hydraulic Servo System Using Evolution Strategies
,”
Control Eng. Pract.
,
14
(
2
), pp.
137
147
.
7.
Chiang
,
M.-H.
,
Chen
,
C.-C.
, and
Jeffrey Kuo
,
C.-F.
,
2009
, “
The High Response and High Efficiency Velocity Control of a Hydraulic Injection Molding Machine Using a Variable Rotational Speed Electro-Hydraulic Pump-Controlled System
,”
Int. J. Adv. Manuf. Technol.
,
43
(
9
), pp.
841
851
.
8.
Daohang
,
S.
,
Vladimir
,
B. B.
, and
Huayong
,
Y.
,
2002
, “
New Model and Sliding Mode Control of Hydraulic Elevator Velocity Tracking System
,”
Simul. Pract. Theory
,
9
(
6–8
), pp.
365
385
.
9.
Alleyne
,
A.
, and
Hedrick
,
J. K.
,
1995
, “
Nonlinear Adaptive Control of Active Suspensions
,”
IEEE Trans. Control Syst. Technol.
,
3
(
1
), pp.
94
101
.
10.
Raade
,
J. W.
, and
Kazerooni
,
H.
,
2005
, “
Analysis and Design of a Novel Hydraulic Power Source for Mobile Robots
,”
IEEE Trans. Autom. Sci. Eng.
,
2
(
3
), pp.
226
232
.
11.
Sirouspour
,
M. R.
, and
Salcudean
,
S. E.
,
2001
, “
Nonlinear Control of Hydraulic Robots
,”
IEEE Trans. Rob. Autom.
,
17
(
2
), pp.
173
182
.
12.
Li
,
G.
, and
Khajepour
,
A.
,
2005
, “
Robust Control of a Hydraulically Driven Flexible Arm Using Backstepping Technique
,”
J. Sound Vib.
,
280
(
3–5
), pp.
759
775
.
13.
Davliakos
,
I.
, and
Papadopoulos
,
E.
,
2009
, “
Impedance Model-Based Control for an Electrohydraulic Stewart Platform
,”
Eur. J. Control
,
15
(
5
), pp.
560
577
.
14.
Plummer
,
A. R.
, and
Vaughan
,
N. D.
,
1996
, “
Robust Adaptive Control for Hydraulic Servosystems
,”
ASME J. Dyn. Syst. Meas. Control
,
118
(
2
), pp.
237
244
.
15.
Yun
,
I. S.
, and
Cho
,
H. S.
,
1988
, “
Adaptive Model Following Control of Electrohydraulic Velocity Control System
,”
Proc. Inst. Electr. Eng.
,
135
(
2
), pp.
149
156
.
16.
Li
,
D.
, and
Salcudean
,
S. E.
,
1997
, “
Modeling, Simulation, and Control of a Hydraulic Stewart Platform
,”
IEEE International Conference on Robotics and Automation
(
ICRA
), Albuquerque, NM, Apr. 20–25, pp.
3360
3366
.
17.
Bobrow
,
J. E.
, and
Lum
,
K.
,
1996
, “
Adaptive, High Bandwidth Control of a Hydraulic Actuator
,”
ASME J. Dyn. Syst. Meas. Control
,
118
(
4
), pp.
714
720
.
18.
Mare
,
J.-C.
,
2006
, “
Dynamic Loading Systems for Ground Testing of High Speed Aerospace Actuators
,”
Aircr. Eng. Aerosp. Technol.
,
78
(
4
), pp.
275
282
.
19.
Plummer
,
A. R.
,
2007
, “
Robust Electrohydraulic Force Control
,”
Proc. Inst. Mech. Eng., Part I
,
221
(
4
), pp.
717
731
.
20.
Jacazio
,
G.
, and
Balossini
,
G.
,
2007
, “
Real-Time Loading Actuator Control for an Advanced Aerospace Test Rig
,”
Proc. Inst. Mech. Eng., Part I
,
221
(
2
), pp.
199
210
.
21.
Vossoughi
,
R.
, and
Donath
,
M.
,
1995
, “
Dynamic Feedback Linearization for Electro-Hydraulically Actuated Control Systems
,”
ASME J. Dyn. Syst. Meas. Control
,
117
(
4
), pp.
468
477
.
22.
Re
,
L. D.
, and
Isidori
,
A.
,
1995
, “
Performance Enhancement of Nonlinear Drives by Feedback Linearization of Linear-Bilinear Cascade Models
,”
IEEE Trans. Control Syst. Technol.
,
3
(
3
), pp.
299
308
.
23.
Shol
,
G. A.
, and
Bobrow
,
J. E.
,
1999
, “
Experimental and Simulations on the Nonlinear Control of a Hydraulic Servo System
,”
IEEE Trans. Control Syst. Technol.
,
7
(
1
), pp.
238
247
.
24.
Seo
,
J.
,
Venugopal
,
R.
, and
Kenne
,
J.-P.
,
2007
, “
Feedback Linearization Based Control of a Rotational Hydraulic Drive
,”
Control Eng. Pract.
,
15
(
12
), pp.
1495
1507
.
25.
Liu
,
Y.
, and
Handroos
,
H.
,
1999
, “
Technical Note Sliding Mode Control for a Class of Hydraulic Position Servo
,”
Mechatronics
,
9
(
1
), pp.
111
123
.
26.
Hong
,
L.
,
Kil
,
T. C.
,
Tae
,
S. N.
, and
Yeong
,
Y. S.
,
2003
, “
Vehicle Longitudinal Brake Control Using Variable Parameter Sliding Control
,”
Control Eng. Pract.
,
11
(
4
), pp.
403
411
.
27.
Bonchis
,
A.
,
Corke
,
P. I.
,
Rye
,
D. C.
, and
Ha
,
Q. P.
,
2001
, “
Variable Structure Methods in Hydraulic Servo Systems Control
,”
Automatica
,
37
(
4
), pp.
589
595
.
28.
Zhang
,
H.
,
Liu
,
X.
,
Wang
,
J.
, and
Karimi
,
H. R.
,
2014
, “
Robust H∞ Sliding Mode Control With Pole Placement for a Fluid Power Electrohydraulic Actuator (EHA) System
,”
Int. J. Adv. Manuf. Technol.
,
73
(
5
), pp.
1095
1104
.
29.
Slotine
,
J.-J. E.
,
1984
, “
Sliding Controller Design for Non-Linear Systems
,”
Int. J. Control
,
40
(
2
), pp.
421
434
.
30.
Hung
,
J. Y.
,
Gao
,
W.
, and
Hung
,
J. C.
,
1993
, “
Variable Structure Control: A Survey
,”
IEEE Trans. Ind. Electron.
,
40
(
1
), pp.
2
20
.
31.
Su
,
J.-P.
,
2001
, “
Robust Control of a Class of Nonlinear Cascade Systems: A Novel Sliding Mode Approach
,”
Proc. IEEE Control Theory Appl.
,
149
(
2
), pp.
131
136
.
32.
Slotine
,
J.-J. E.
, and
Li
,
W.
,
1991
,
Applied Nonlinear Control
,
Prentice Hall, Upper Saddle River
,
NJ
.
33.
Duan
,
S. L.
,
An
,
G. C.
, and
Xue
,
J.
,
2002
, “
Adaptive Sliding Mode Control for Electrohydraulic Servo Force Control Systems
,”
Chin. J. Mech. Eng.
,
38
(
5
), pp.
109
113
.
34.
Chen
,
H.-M.
,
Renn
,
J.-C.
, and
Su
,
J.-P.
,
2005
, “
Sliding Mode Control With Varying Boundary Layers for an Electro-Hydraulic Position Servo System
,”
Int. J. Adv. Manuf. Technol.
,
26
(
1
), pp.
117
123
.
35.
Song
,
X.
,
Park
,
Y.
, and
Park
,
J.
,
2013
, “
Blowdown Prediction of a Conventional Pressure Relief Valve With a Simplified Dynamic Model
,”
Math. Comput. Model
,
57
(
2
), pp.
279
288
.
36.
Craig
,
J. J.
,
2005
,
Introduction to Robotics Mechanics and Control
,
Prentice Hall
, Upper Saddle River,
NJ
.
37.
Yang
,
W. C.
, and
Tobler
,
W. E.
,
1991
, “
Dissipative Modal Approximation of Fluid Transmission Lines Using Linear Friction Model
,”
ASME J. Dyn. Syst. Meas. Control
,
113
(
1
), pp.
152
162
.
38.
Guan
,
C.
, and
Pan
,
S.
,
2008
, “
Nonlinear Adaptive Robust Control of Single-Rod Electro-Hydraulic Actuator With Unknown Nonlinear Parameters
,”
IEEE Trans. Control Syst. Technol.
,
16
(
3
), pp.
434
445
.
39.
Karpenko
,
M.
, and
Sepehri
,
N.
,
2007
, “
Decentralized Coordinated Motion Control of Two Hydraulic Actuators Handling a Common Object
,”
ASME J. Dyn. Syst. Meas. Control
,
129
(
5
), pp.
729
741
.
This content is only available via PDF.
You do not currently have access to this content.