Complex order control for improved loop-shaping in precision positioning
Abstract
This paper presents a complex order filter developed and subsequently integrated into a PID-based controller design. The nonlinear filter is designed with reset elements to have describing function based frequency response similar to that of a linear (practically non-implementable) complex order filter. This allows for a design which has a negative gain slope and a corresponding positive phase slope as desired from a loop-shaping controller-design perspective. This approach enables improvement in precision tracking without compromising the bandwidth or stability requirements. The proposed designs are tested on a planar precision positioning stage and performance compared with PID and other state-of-the-art reset based controllers to showcase the advantages of this filter.
Cite
@article{arxiv.1907.09249,
title = {Complex order control for improved loop-shaping in precision positioning},
author = {Niranjan Saikumar and Duarte Valério and S. Hassan HosseinNia},
journal= {arXiv preprint arXiv:1907.09249},
year = {2020}
}