A novel low power control technique along with a new class of actuators is developed for shock isolation and control of structural vibrations. In contrast to other techniques, including conventional viscous or rate damping, the force produced by the actuator has no velocity dependence. Several experimental, analytical, and simulation results are presented in support of this new, semi-active technique for structural control. The basic approach is to manipulate the system stiffness through the use of resetable actuators. With the proposed control approach, the actuator behaves like a linear spring. However, at appropriate times, the effective unstretched length of the actuator is changed—or reset—to extract energy from the vibrating structure. Experimental validation of the actuator model, analytical results on stability and actuator-placement, and simulation results for earthquake applications are presented. [S0022-0434(00)01603-8]

Issue Section:
Technical Briefs
Keywords:
structural engineering, vibration control, damping, actuators, pneumatic control equipment, variable structure systems, Lyapunov methods
Topics:
Actuators, Stiffness, Damping, Shock isolation
1.
Kobori, T., and Kamagata, S., 1991, “Dynamic Intelligent Buildings: Active Seismic Response Control” Intelligent Structures; Monitoring and Control, Y. K. Wen, ed., Elsevier Applied Science, N. Y., pp. 279–282.
2.
Leitmann
,
G.
, and
Reithmeirer
,
E.
,
1993
, “
Semiactive Control of a Vibrating System by Means of Electrorheological Fluids
,”
Dynam. Control
,
3
, No.
1
, pp.
7
–
34
.
3.
Patten, W. N., and Sack, R. L., 1994, “Semiactive Control of Civil Engineering Structures,” Proceedings of the 1994 ACC, Baltimore, MD, pp. 1078–1082.
4.
Gavin
,
H. P.
,
Hanson
,
R. D.
, and
Filisko
,
F. E.
,
1996
, “
Electrorheological Damper:1. Analysis and Design
,”
ASME J. Appl. Mech.
,
63
, No.
3
, pp.
669
–
682
.
5.
Utkin
,
V. I.
,
1977
, “
Variable Structure Systems with Sliding Modes
,”
IEEE Trans. Autom. Control
,
22
, No.
2
, pp.
212
–
222
.
6.
Nemir
,
D.
,
Lin
,
Y.
, and
Osegueda
,
R.
,
1994
, “
Semi-active Motion Control Using Variable Stiffness
,”
J. Struct. Eng.
,
120
, No.
4
, Apr., pp.
1291
–
1306
.
7.
Yang
,
J. N.
,
Li
,
Z.
, and
Wu
,
J. C.
,
1996
, “
Control of seismic excited-buildings using active variable stiffness system
,”
Eng. Struct.
,
18
, No.
8
, pp.
589
–
596
.
8.
Nagarajaiah, S., 1997, “Semi-active Control of Structures,” Proceedings of Structural Congress, 1997, ASCE, Portland, Oregon, pp. 1574–1578.
9.
Bobrow
,
J. E.
,
Jabbari
,
F.
, and
Thai
,
K.
,
1995
, “
An Active Truss Element and Control Law for Vibration Suppression
,”
J. Smart Struct. Mater.
,
4
, pp.
264
–
269
.
10.
Thai, K., Jabbari, F., and Bobrow, J. E., 1995, “Vibration Suppression through Parametric Control: A General Framework,” Proceedings of 1995 IMECE (International Mechanical Engineering Congress and Exposition), The Winter Annual Meeting of the ASME, San Francisco, CA.
11.
Thai, K., 1997, “Parametric methods for vibration suppression,” Ph.D. dissertation, Department of Mechanical and Aerospace Engineering, University of California, Irvine.
12.
Srisamang, R. E., 1997, “An experimental investigation of a new structural damping device,” M.S. project, Department of Mechanical and Aerospace Engineering, University of California, Irvine.
13.
Inaudi
,
J. A.
,
Leitmann
,
G.
, and
Kelly
,
J. M.
,
1994
, “
Single Degree of Freedom Nonlinear Homogeneous Systems
,”
J. Eng. Mech.
,
120
, No.
7
, pp.
1543
–
1562
.
Copyright © 2000
 by ASME
You do not currently have access to this content.