What is System Identification?
System Identification refers to the general process of extracting information about a system from measured input-output data. A typical outcome is an identification model which may be static or dynamic, deterministic or stochastic, linear or nonlinear. One can use such a model for simulation, controller design, or analysis. System identification can also be used to extract information other than a model of a system. For example, it can be used to identify the system controllability matrix, the system observability matrix, an observer or Kalman filter gain, existing feedback controller gain, disturbance environment, or to detect actuator and sensor failure. The same theory can even be used to synthesize feedback or feedforward controller gains directly from a set of input-output data without obtaining an intermediate model of the system first.
Recent Highlights:
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Goodzeit, N.E. and Phan, M.Q., "An Intelligent Adaptive System for Flexible Spacecraft Identification and Disturbance Rejection," Journal of Vibration and Control, in press.
Goodzeit, N.E. and Phan, M.Q., "System and Disturbance Identification for Feedforward-Feedback Control Applications," Journal of Guidance, Control, and Dynamics, accepted for publication.
Phan, M.Q. and Frueh, J.A., "System Identification and Learning Control," Iterative Learning Control: Analysis, Design, Integration, and Applications, Chapter 15, Bien Z. and Xu, J. (eds.), Kluwer Academic Publishing, Norwell, MA, 1998, pp. 285-306.
Phan, M.Q., OKID: Step-by-Step Guide and References, Department of Mechanical and Aerospace Engineering, Princeton University, 1997.
Goodzeit, N.E . and Phan, M.Q., "System and Periodic Disturbance Identification for Feedforward-Feedback Control of Flexible Spacecraft," Proceedings of the 35th AIAA Aerospace Sciences Meeting and Exhibit, Reno, Nevada, January 1997.
Goodzeit, N.E. and Phan, M.Q., "Exact System Identification in the Presence of Completely Unknown Periodic Disturbances," Journal of Guidance, Control, and Dynamics, accepted for publication. Also, Department of Mechanical and Aerospace Engineering Technical Report No. 2096, Princeton University, 1997.
Phan, M.Q., Goodzeit, N.E., and Juang, J.-N., "Identification of Systems and Periodic Disturbances," Paper DETC97/VIB-4256, Proceedings of the 1997 ASME Design Engineering Technical Conferences, Sacramento, CA, September 1997.
Phan, M.Q., Goodzeit, N.E., and Juang, J.N., "Identification of Input-Output Model and Periodic Disturbance From Disturbance-Corrupted Data," Journal of Vibration and Acoustics, submitted.
Phan, M.Q., Lim, R.K., and Longman, R.W., "Unifying Input-Output and State-Space Perspectives of Predictive Control," Department of Mechanical and Aerospace Engineering Technical Report No. 3044, Princeton University, Sept. 1998 (submitted for publication).
Lim, R.K., Phan, M.Q., and Longman, R.W.,"State Space System Identification with Identified Hankel Matrix," Department of Mechanical and Aerospace Engineering Technical Report No. 3045, Princeton University, Sept. 1998 (submitted for publication).
Lim, R.K., Phan, M.Q., and Longman, R.W.,"State Estimation with ARMarkov Models," Department of Mechanical and Aerospace Engineering Technical Report No. 3046, Princeton University, Oct. 1998 (submitted for publication).
Lim, R.K., and Phan, M.Q., "Identification of a Multistep-Ahead Observer and Its Application to Predictive Control," Journal of Guidance, Control, and Dynamics, Vol. 20, No. 6, November-December 1997, pp. 1200-1206.
Phan, M.Q., Juang, J.-N., and Longman, R.W., "Markov Parameters in System Identification: Old and New Concepts," Structronic Systems: Smart Structures, Devices, and Systems, Vol. 2, Tzou, H.S. and Guran A. (eds.), World Scientific, Singapore, 1997, pp. 263-293.
Phan, M.Q., Horta, L.G., Juang, J.-N., and Longman, R.W., "Improvement of Observer/Kalman Filter Identification (OKID) by Residual Whitening," Journal of Vibrations and Acoustics, Vol. 117, April 1995, pp. 232-238.
Phan, M.Q., Juang, J.-N., and Hyland, D.C., "On Neural Networks in Identification and Control of Dynamic Systems," Wave Motion, Intelligent Structures, and Nonlinear Mechanics, Guran, A. and Inman, D. (eds.), pp. 194-225, World Scientific, 1995.
Phan, M.Q., Juang, J.-N., Horta, L.G., and Longman, R.W., "System Identification from Closed-Loop Data with Known Output Feedback Dynamics," Journal of Guidance, Control, and Dynamics, Vol. 17, No. 4, July-August 1994, pp. 661-669.
Juang, J.-N. and Phan, M., "Linear System Identification Via A Backward-Time Observer," Journal of Guidance, Control, and Dynamics, Vol. 17, No. 3, May-June 1994, pp. 505-512.
Juang, J.-N. and Phan, M., "Identification of System, Observer, and Controller from Closed-loop Experimental Data," Journal of Guidance, Control, and Dynamics, Vol. 17, No. 1, Jan.-Feb. 1994, pp. 91-96.
Phan, M., Horta, L.G., Juang, J.N., and Longman, R.W., "Linear System Identification Via An Asymptotically Stable Observer," Journal of Optimization Theory and Applications, Vol. 79, No. 1, pp. 59-86, October 1993. An earlier and more detailed version of this paper appeared as NASA Technical Paper TP-3164, Langley Research Center, Hampton, VA., June 1992.
Chen, C.-W., Juang, J.-N., and Phan, M., "Estimation of Kalman Filter Gain from Output Residuals," Journal of Guidance, Control, and Dynamics, Vol. 16, No. 5, September-October 1993, pp. 903-908.
Juang, J.-N., Phan, M., Horta, L.G., and Longman, R.W."Identification of Observer/Kalman Filter Markov Parameters: Theory and Experiments," Journal of Guidance, Control, and Dynamics, Vol. 16, No. 2, March-April 1993, pp. 320-329.
Phan, M., Juang, J.-N., and Longman, R.W., "Identification of Linear Multivariable Systems by Identification of Observers with Assigned Real Eigenvalues," Journal of the Astronautical Sciences, Vol. 40, No. 2, April-June 1992, pp. 261-279.
Chen, C.-W., Huang, J.-K., Phan, M., and Juang, J.-N."Integrated System Identification and Modal State Estimation for Control of Large Flexible Space Structures," Journal of Guidance, Control, and Dynamics, Vol. 15, No. 1, pp. 88-95, Jan.-Feb. 1992.
For additional references on this topic, please refer to List of Publications.