Improvement on adaptive forward prediction controller using a direct-compensation technique

Abstract

Hybrid testing method of dynamically substructured system is used for performance evaluation of engineering systems. During the tests, an entire engineering system is decomposed into software simulation and physical hardware substructures. Linear and well-understood parts are simulated numerically, and uncertain specimens are tested physically. The success of the tests relies on a high-quality controller to cancel the unwanted dynamics introduced by actuators within the physical substructures, thus synchronizing the numerical and physical responses at the interface. Delay compensation techniques are commonly used in dealing with the substructuring control issues. This paper proposes a new direct-compensation strategy to define the initial condition of an adaptive delay-prediction controller, without using a priori information about the tested components' parameters. Meanwhile, singular value decomposition method is applied to the control synthesis procedure, in order to reduce the numerical sensitivity of the controller, providing with the possibility of achieving a high-level accuracy of the tests. Experimental results are included, which favorably verify the proposed improvement strategies.

Modelling and control issues of dynamically substructured systems: adaptive forward prediction taken as an example

“…To address these two issues and thereby improve the AFP performance, SVD and direct-compensation methods are introduced in §3b [7]. The implementation results, based on two mechanical systems, are presented in §3c to verify the proposed improvement strategies.…”

“…The SVD method is, therefore, applied to reduce numerical sensitivity around the matrix operation, and a direct-compensation method is proposed to parametrize P in a relatively optimal and straightforward manner [7] without the prior use of the Σ 1 and Σ 2 parameters.…”

“…The AFP algorithm is summarized in §2, following the notation system of figure 1a; this makes it possible to reinterpret the AFP algorithm in a more systematic manner, and to offer common ground for further comparison of the DSS control strategies in §3c. In §3, new direct-compensation and singular value decomposition (SVD) methods are introduced to improve AFP performance [7]. In order to demonstrate the concepts involved, implementation studies of two DSSs are presented in §3c as examples, and the AFP controller is compared with a linear dynamics-based controller in [6].…”

“…[1][2][3][4][5]). In order to help present the DSS concepts and synthesize the associated dynamics in a systematic manner, a nominal substructured framework is displayed in figure 1a [6,7], in which the original, entire engineering system to be tested is called an emulated system. The emulated system is broken down into at least two heterogeneous subsystems.…”

“…DSS framework and example from the literature: (a) the substructured framework for the nominal case [6,7] and (b) the emulated MSDP system [8,9]. physical process, are applied to investigate the dynamic behaviour of a wide range of structural systems (e.g.…”