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Research Papers

Load Recovery in Components Based on Dynamic Strain Measurements

[+] Author and Article Information
Anoop K. Dhingra

e-mail: dhingra@uwm.edu

Deepak K. Gupta

Department of Mechanical Engineering,
University of Wisconsin,
Milwaukee, WI 53201

1Corresponding author.

2Currently President, Wolf Star Technologies, 3321 N. Newhall St., Milwaukee, WI 53211, e-mail: tim.hunter@wolfstartech.com.

Contributed by the Design Engineering Division of ASME for publication in the JOURNAL OF VIBRATION AND ACOUSTICS. Manuscript received March 5, 2012; final manuscript received April 26, 2013; published online June 18, 2013. Assoc. Editor: Jean Zu.

J. Vib. Acoust 135(5), 051020 (Jun 18, 2013) (8 pages) Paper No: VIB-12-1056; doi: 10.1115/1.4024384 History: Received March 05, 2012; Revised April 26, 2013

This paper presents a modeling approach for estimating time varying loads acting on a component from experimental strain measurements. The strain response of an elastic vibrating system is written as a linear superposition of strain modes. Since the strain modes, as well as the normal displacement modes, are intrinsic dynamic characteristics of a component, the dynamic loads exciting a component are estimated by measuring induced strain fields. The accuracy of the estimated loads depends on a number of factors, such as the placement locations and orientations of the gauges on the instrumented structure, as well as the number of retained modes from strain modal analysis. A solution procedure based on the construction of D-optimal designs is implemented to determine the optimum locations and orientations of strain gauges such that the variance in load estimates is minimized. A numerical as well as an experimental validation of the proposed approach through two example problems is also presented.

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References

Ewins, D. J., 2000, Modal Testing: Theory, Practice, and Applications, Research Studies Press Ltd., Baldock, UK.
Hillary, B., and Ewins, D. J., 1984, “The Use of Strain Gages in Force Determination and Frequency Response Function,” Proceedings of the 2nd International Modal Analysis Conference (IMAC), Orlando, FL, February 6–9, pp. 627–634.
Bernasconi, O., and Ewins, D. J., 1989, “Modal Strain/Stress Fields,” J. Modal Anal., 4(2), pp. 68–76.
Li, D. B., Zhuge, H., and Wang, B., 1989, “The Principles and Techniques of Experimental Strain Modal Analysis,” Proceedings of the 7th International Modal Analysis Conference (IMAC), Las Vegas, NV, January 30-February 2, pp. 1285–1289.
Tsang, W. F., 1990, “Use of Dynamic Strain Measurements for the Modeling of Structures,” Proceedings of the 8th International Modal Analysis Conference (IMAC), Kissimmee, FL, January 29-February 1, pp. 1246–1251.
Yam, L. H., Leung, T. P., Li, D. B., and Xue, K. Z., 1996, “Theoretical and Experimental Study of Modal Strain Analysis,” J. Sound Vib., 191(2), pp. 251–260. [CrossRef]
Sommerfeld, J. L., and Meyer, R. A., 1999, “Correlation and Accuracy of a Wheel Force Transducer as Developed and Tested on a Flat-Trac® Tire Test System,” SAE Paper No. 1999-01-0938. [CrossRef]
Masroor, S. A., and Zachary, L. W., 1990, “Designing an All-Purpose Force Transducer,” Exp. Mech., 31(1), pp. 33–35. [CrossRef]
Wickham, M. J., Riley, D. R., and Nachtsheim, C. J., 1995, “Integrating Optimal Experimental Design Into the Design of a Multi-Axis Load Transducer,” ASME J. Eng. Ind., 117(3), pp. 400–405. [CrossRef]
Szwedowicz, J., Senn, S. M., and Abhari, R. S., 2002, “Optimum Strain Gage Application to Bladed Assemblies,” ASME J. Turbomach., 124(4), pp. 606–613. [CrossRef]
Mignolet, M. P., and Choi, B. K., 2003, “Robust Optimal Positioning of Strain Gages on Blades,” ASME J. Turbomach., 125(1), pp. 155–164. [CrossRef]
Galil, Z., and Kiefer, J., 1980, “Time- and Space-Saving Computer Methods, Related to Mitchell's DETMAX, for Finding D-Optimum Designs,” Technometrics, 22(3), pp. 301–313. [CrossRef]
Mitchell, T. J., 1974, “An Algorithm for the Construction of D-Optimal Experimental Designs,” Technometrics, 16(2), pp. 203–210. [CrossRef]
Atkinson, A. C., and Donev, A. N., 1992, Optimum Experimental Designs, Oxford University Press, New York.
Budynas, R. G., 1999, Advanced Strength and Applied Stress Analysis, 2nd ed., McGraw-Hill, New York.
Chatterjee, S., and Hadi, A. S., 1988, Sensitivity Analysis in Linear Regression, John Wiley, New York.

Figures

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Fig. 1

Flow chart of the overall solution process

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Fig. 2

Bent beam with its four modes

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Fig. 3

Optimum gauge locations and orientations

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Fig. 4

Load-time history applied at the tip of the beam

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Fig. 5

Recovered mode participation factors

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Fig. 6

Cantilevered beam with optimum gauge placement

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Fig. 7

Clamped cantilevered beam mounted on the shaker

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Fig. 8

MPF for a 28 Hz base excitation

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Fig. 9

Recovered MPF for a 28 Hz input

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Fig. 10

Actual and reconstructed strains in gauge 1

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Fig. 11

Actual and reconstructed strains in gauge 3

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