Hostname: page-component-586b7cd67f-2brh9 Total loading time: 0 Render date: 2024-11-24T17:47:35.418Z Has data issue: false hasContentIssue false
  • English
  • Français

Modal control using real-time identification for time-varyingstructures

Published online by Cambridge University Press:  22 December 2010

Fengyan Deng ,
Didier Rémond  and
Luc Gaudiller
Get access

Abstract

For a controlled structure, the changes of physical characteristics like naturalfrequencies, modal damping coefficients, and what’s more on mode shapes will destabilizethe controlled system. To keep the control performance and guarantee its robustness, a newmodal control method using real-time identification is proposed to overcome theinstability of controlled structure, especially induced by the inversion of mode shape. Inthis paper, a modal model of time-varying mechanical structure is supplied by anidentifier. The choice of the kind of control permits to use this time-varying model foroptimizing and self-adapting the controller. In order to supply the controller, a modalobserver is used and also updated. For illustrative purpose, this proposed methodology iscarried out on a simple but representative time-varying mechanical structure. On thisexample, an inertia modification leads not only to low modal frequency shifts but also toinversion of a mode shape. This mode shape inversion is shown to destabilize thecontrolled structure when the control system is not updated. The overall procedure will bedescribed through simulations and performed for different operating conditions, which willprove that mode shapes have to be precisely determined and updated in the controller andobserver to guarantee a robust modal control with high performances in spite of thechanges of structure.

Keywords

Self-adaptive controlreal-time identificationmodal controlmode shapestabilitystructurerobustness
Type
Research Article
Information
Mechanics & Industry , Volume 11 , Issue 6: VCB (Vibrations, Chocs et Bruits) , November 2010 , pp. 513 - 520
Copyright
© AFM, EDP Sciences 2010

Access options

Get access to the full version of this content by using one of the access options below. (Log in options will check for institutional or personal access. Content may require purchase if you do not have access.)

References

Références

Postlethwaite, I., Turner, M.C., Herrmann, G., Robust control applications, Annu. Rev. Control 31 (2007) 27–39 CrossRefGoogle Scholar
Anderson, B.D., Dehghani, A., Challenges of adaptive control-past, permanent and future, Annu. Rev. Control 32 (2008) 123–135 CrossRefGoogle Scholar
Gaudiller, L., Bochard, S., Adaptive active control of flexible structures subjected to rigid body displacements, J. Sound Vib. 283 (2005) 311–339 CrossRefGoogle Scholar
Van Den Hof, P.M., Schrama, R.J., Identification and control closed-loop issues, Automatica 31 (1995) 1751–1770 CrossRefGoogle Scholar
Gevers, M., A decade of progress in iterative process control design: From theory to practice, J. Process Control 12 (2002) 519–531 CrossRefGoogle Scholar
T. Katayama, Subspace methods for system identification, Springer-Verlag, London, 2005
H. Luş, Control theory based system identification, Ph.D. Thesis, Columbia University, New York, 2001
L. Renaudin, D. Rémond, Modal Behavior Monitoring of a Discrete Evolutive Structure, Proceedings of the 15th IFAC symposium on System Identification, St Malo, France, 2009
P. Van Overschee, B. De Moor, Subspace identification for linear systems: Theory implementation applications, Kluwer Academic Publishers, Dordrecht, Netherlands, 1996
De Angelis, M., Luş, H., Betti, R., Longman, R., Extracting physical parameters of mechanical models from identified state-space representations, J. Appl. Mech. Trans. ASME 69 (2002) 617–625 CrossRefGoogle Scholar
Balmès, E., New results on the identification of normal modes from experimental complex modes, Mechanical Systems and Signal Processing 11 (1997) 229–243 CrossRefGoogle Scholar