Presented below is a summary of the results obtained to date on the verification of a novel state space model identification technique called PLID (Pseudo Linear IDentification), given in Hopkins et al.1 This technique has several unique features that include: (1) optimal joint parameter and state estimation (that gives rise to its nonlinearities); (2) provisions for sensor, actuator, and state noise; (3) and it converges almost surely to the true plant parameters provided that the plant is linear, completely controllable/observable, strictly proper, time invariant, and all noise sources are zero mean white gaussian (ZMWG). Experiments carried out on a flexible, modally dense 3-D truss structure standing 4 feet tall have shown PLID to be a robust technique capable of managing significant deviations from the assumptions made to prove strict optimality. Using the 3 actuators and 3 sensors attached to the structure, models varying in size from 24 to 64 states have been used to approximate this infinite dimensional testbed in the frequency range between 50 to 500 Hz. Sensor signals with RMS levels of approximately 2 volts have been predicted by PLID to within 0.01 volts RMS.

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Copyright 1995 Society of Photo-Optical Instrumentation Engineers. This paper was published by SPIE and is made available as an electronic reprint (preprint) with permission of SPIE. One print or electronic copy may be made for personal use only. Systematic or multiple reproduction, distribution to multiple locations via electronic or other means, duplication of any material in this paper for a fee or for commercial purposes, or modification of the content of the paper are prohibited. Conference proceedings of the SPIE North American conference on smart structures and materials. Please see for more information. Note: imported from RIT’s Digital Media Library running on DSpace to RIT Scholar Works in February 2014.

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Conference Proceeding

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Microelectronic Engineering (KGCOE)


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