MX Filters: A New Tool for Performance Tests of Adaptive Structural Systems

Abstract

This paper describes a new measuring technique tool that allows the on-line iden tification of adaptive structural systems or other dynamic time-variant systems or processes. It is based on the adaptive modelling concept. The main ideas of this method are the MX filter, the corre sponding adaptation algorithm MX-LMS, and further calculations to yield the unknown behavior of the intelligent materials or material systems from the adapted MX filter coefficients. It is shown that the proposed system identification procedure is extremely fast and copes with the requirement of MDOF systems, real-time conditions and time-variations of the system to be identified. Experiments on a carbon fibre reinforced epoxy beam with embedded NiTi wires demonstrate that the structural parameters to be identified are known at any time, even in cases in which they are time-varying, e.g., when the NiTi wires are activated by electrical current.

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