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arXiv · 2406.16263

Discrete-time Integral Resonant Control of Negative Imaginary Systems: Application to a High-speed Nanopositioner

Kanghong Shi·Erfan Khodabakhshi·Prosanto Biswas·Ian R. Petersen·S. O. Reza Moheimani
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Abstract

We propose a discrete-time integral resonant control (IRC) approach for negative imaginary (NI) systems, which overcomes several limitations of continuous-time IRC. We show that a discrete-time IRC has a step-advanced negative imaginary property. A zero-order hold-sampled NI system can be asymptotically stabilized using a discrete-time IRC with suitable parameters. A hardware experiment is conducted where a high-speed flexure-guided nanopositioner is efficiently damped using the proposed discrete-time IRC with the discrete-time controller being implemented in FPGA hardware at the sampling rate of 1.25 MHz.

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Kanghong Shi, Erfan Khodabakhshi, Prosanto Biswas, Ian R. Petersen, S. O. Reza Moheimani. 2024-06-24. Discrete-time Integral Resonant Control of Negative Imaginary Systems: Application to a High-speed Nanopositioner. https://arxiv.org/abs/2406.16263

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