This paper elaborates upon a novel concept, the Delayed Resonator, a tunable active vibration absorber. This technique uses a control which has a time delayed feedback of the absorber mass displacement. The substance of this process is in that the absorber completely removes oscillations from the primary structure. Two very strong features that should be mentioned are: (a) the excitation frequency range can vary over a semi-infinite interval, and (b) the absorber can be tuned in real time. These are the unique characteristics of the technique distinguishing it from the others. Stability issues of the primary system combined with the Delayed Resonator are addressed following Nyquist and root locus methods. In particular, the absorption performance for cases with time varying excitation frequency is studied. The primary focus of this paper is on the analysis of transient absorption behavior of the Delayed Resonator during its tuning. An example case is provided which considers a step change in the excitation frequency. A well-pronounced manifestation of the tunability feature of the Delayed Resonator is observed. The superiority of the Delayed Resonator absorber over the conventional a priori tuned absorbers is also demonstrated.

Issue Section:
Technical Papers
Topics:
Vibration absorbers, Excitation, Absorption, Displacement, Feedback, Oscillations, Stability, Transients (Dynamics)
1.
Ackermann, J., 1977, “Entwurf durch Polvorgabe,” Regelungstechnik und Prozess-Datenverarbeitung, No. 6–7, pp. 173–179, 209–215.
2.
Abdel-Mooty, M., and Roorda, J., 1991, “Time Delay Compensation in Active Damping of Structures,” Journal of Engineering Mechanics, Vol. 117, No. 11.
3.
Chen, C. T., 1984, Linear Systems Theory and Design, Holt, Rinehart and Winston, New York.
4.
Hertz, D., Jury, E. I., and Zeheb, E., 1984, “Simplified Analytic Stability Test for Systems with Commensurate Time Delays,” IEE Proceedings, Vol. 131, Part D, No. 1.
5.
Inman, D. J., 1994, Engineering Vibration, Prentice-Hall, Englewood Cliffs, NJ.
6.
Inman, D. J., 1989, Vibration: With Control, Measurement and Stability, Prentice-Hall, Englewood Cliffs, NJ.
7.
Kailath, T., 1980, Linear Systems, Prentice-Hall, Englewood Cliffs, NJ.
8.
Kuo, B. C., 1982, Automatic Control Systems, 4th ed., Prentice-Hall, Englewood Cliffs, NJ.
9.
Leipholz, H. H. E., and Abdel-Rohman, M., 1986, Control of Structures, Martinus Nijhoff, Dordrecht, The Netherlands.
10.
Olgac, N., and Holm-Hansen, B., 1994a, “A Novel Active Vibration Absorption Technique: Delayed Resonator,” To appear Journal of Sound and Vibration.
11.
Olgac, N., and Holm-Hansen, B., 1994b, “Tunable Active Vibration Absorber: The Delayed Resonator, Design Considerations,” To appear Journal of Engineering Mechanics.
12.
Olgac, N., and Holm-Hansen, B., 1993, “Vibration Absorbers Utilizing Only Position Measurements for Time Varying Excitation Frequencies,” Symposium on Mechatronics, ASME DSC-Vol. 50.
13.
Olgac, N., McFarland, D. M., and Holm-Hansen, B., 1992, “Position Feedback-Induced Resonance: The Delayed Resonator,” ASME Winter Annual Meeting, Los Angeles, CA.
14.
Olgac, N., and Zhao, G., 1987, “A Relative Stability Study on the Dynamics of the Turning Mechanism,” ASME JOURNAL OF DYNAMIC SYSTEMS, MEASUREMENT, AND CONTROL, Vol. 109.
15.
Phillips, C. L., and Harbor, R. D., 1988, Feedback Control Systems, Prentice-Hall, Englewood Cliffs, NJ.
16.
Rodellar, J., Chung, L. L., Soong, T. T., Reinhorn, A. M., 1989, “Experimental Digital Control of Structures,” Journal of Engineering Mechanics, Vol. 115, No. 6.
17.
Satche, M., 1949, “Discussion on “Stability of Linear Oscillating Systems With Constant Time Lag,” ASME Journal of Applied Mechanics, Vol. 16.
18.
Soong, T. T., 1990, Active Structural Control: Theory and Practice, Wiley, New York.
19.
Soong, T. T., Reinhorn, A. M., Wang, Y. P., and Lin, R. C., 1991, “Full-Scale Implementation of Active Control. I: Design and Simulation, Journal of Structural Engineering, Vol. 117, No. 11.
20.
Thowsen, A., 1982, “Delay-Independent Asymptotic Stability of Linear Systems,” IEE Proceedings, Vol. 129, Part D, No. 3.
21.
Yang, B., 1991, “Noncolocated Control of a Damped String Using Time Delay,” Proceedings of the 1991 American Control Conference, Vol. 3, Boston, MA.
22.
Yang, J. N., 1988, “Recent Advances in Active Control of Civil Engineering Structures,” Journal of Probabilistic Engineering Mechanics, Vol. 3.
23.
Youcef-Toumi, K., and Bobbett, J., 1991, “Stability of Uncertain Linear Systems with Time Delay,” ASME JOURNAL OF DYNAMIC SYSTEMS, MEASUREMENT, AND CONTROL, Vol. 113.
This content is only available via PDF.
Copyright © 1995
 by The American Society of Mechanical Engineers
You do not currently have access to this content.