A new class of distributed sensors is presented which can measure both the linear and angular deflections of composite beams. The sensor relies in its operation on a set of wires which are embedded off the neutral axes of the composite beams. The wires are arranged in a special manner which allows continuous monitoring of the deflection curve of the beam. The output signals of the wires are processed to determine the linear and angular displacements at critical discrete points along the beam axis. The theoretical and experimental performance of the sensor is presented in both the time and frequency domains. Comparisons are given between the experimental performance of the distributed sensor and that of conventional laser sensors in order to demonstrate the accuracy and merits of the distributed sensor. The results obtained suggest the potential of this new class of sensors as a viable means for monitoring the static and dynamic deflections of flexible composite SMART beams and plates.

1.
Baz
A.
,
Poh
S.
, and
Gilheany
J.
,
1993
, “
A Multi-Mode Distributed Sensor for Vibrating Beams
,”
J. of Sound & Vibration
, Vol.
165
, No.
3
, pp.
481
495
.
2.
Cox
D.
,
Thomas
D.
,
Reichard
K.
,
Lindner
D.
, and
Claus
R. O.
,
1989
, “
Modal Domain Fiber Optic Sensor for Closed Loop Vibration Control of a Flexible Beam
,”
Proc. of SPIE on Fiber Optic Smart Structures and Skins II
, Vol.
1170
,
372
383
.
3.
Fenner, R., 1975, Finite Element Methods for Engineers, MacMillan, London.
4.
Fuller, C., Rogers, C. A., and Robertshaw, H H., 1989, “Active Structural Acoustic With Smart Structures,” Proc. of SPIE Conference on Fiber Optic Smart Structures and Skins II, Vol. 1170, pp. 338–358.
5.
Lang, E. J., and Chou, T. W., 1994, “Modal Filtering Using Lineal Sensors,” Proc. of AIAA/ASME Adaptive Structures Forum, Hilton Head, NC, Paper #AIAA-94-1741-CP, pp. 95–100.
6.
Lee, C. K., 1987, “Piezoelectric Laminates for Torsional and Bending Modal Control: Theory and Experiments,” Ph.D. thesis, Cornell University.
7.
Lee, C. K., O’Sullivan, T. C., and Chiang, W. W., 1991, “Piezoelectric Strain Rate Sensor and Actuator Designs for Active Vibration Control,” Proc. of 32 SDM Conference, Paper AIAA-91-1064-CP, 2197-2207.
8.
Meirovitch, L., 1967, Analytical Methods in Vibration, New York, Macmillan.
9.
Meirovitch
L.
, and
Baruh
H.
,
1985
, “
The Implementation of Modal Filters for Control of Structures
,”
J. of Guidance & Control
, Vol.
8
, No.
6
, pp.
707
716
.
10.
Murphy
K.
,
Miller
M.
,
Vengsarkar
A.
, and
Claus
R. O.
,
1991
, “
Elliptical-Core, Dual-Mode, Optical Fiber Strain and Vibration Sensors for Composite Material Laminates
,”
J. of Composites Technology & Research
, Vol.
13
, pp.
29
35
.
11.
Rockey, K. C., Evans, H. R., Griffiths, D. W., and Nethercot, D. A., 1983, The Finite Element Method, Second Edition, England, Halsted Press.
12.
Salazano, T. B., 1990, “Integrated Strain Measurements in Composite Members Using Embedded Constantan Wire,” Master’s Project Report, Department of Mechanical Engineering, Oregon State University, Corvallis, OR.
13.
Sendeckyj, G. P., and Paul, C. A., 1989, “Some Smart Structures Concepts,” Proc. of SPIE Conference on Fiber Optic Smart Structures and Skins II, Vol. 1170, pp. 2–10.
14.
Wilson, D., Anderson, J., Rempt, R., and Ikegami, R., 1990, “Shape Memory Alloys and Fiber Optics for Flexible Structure Control,” Proc. of SPIE Conference on Fiber Optic Smart Structures and Skins III, Vol. 1370-25.
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