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arXiv · 2503.01344

Local Rational Modeling for Identification Beyond the Nyquist Frequency: Applied to a Prototype Wafer Stage

Max van Haren·Lennart Blanken·Koen Classens·Tom Oomen
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Abstract

Fast-rate models are essential for control design, specifically to address intersample behavior. The aim of this paper is to develop a frequency-domain non-parametric identification technique to estimate fast-rate models of systems that have relevant dynamics and allow for actuation above the Nyquist frequency of a slow-rate output. Examples of such systems include vision-in-the-loop systems. Through local rational models over multiple frequency bands, aliased components are effectively disentangled, particularly for lightly-damped systems. The developed technique accurately determines non-parametric fast-rate models of systems with slow-rate outputs, all within a single identification experiment. Finally, the effectiveness of the technique is demonstrated through experiments conducted on a prototype wafer stage used for semiconductor manufacturing.

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Max van Haren, Lennart Blanken, Koen Classens, Tom Oomen. 2025-03-03. Local Rational Modeling for Identification Beyond the Nyquist Frequency: Applied to a Prototype Wafer Stage. https://doi.org/10.1109/tcst.2025.3568550

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