$H_{\mathrm{\infty }}$ Performance Analysis for Almost Periodic Piecewise Linear Systems with Application to Roll-to-Roll Manufacturing Control

An almost periodic piecewise linear system (APPLS) is a type of piecewise linear system where the system cyclically switches between different modes, each with an uncertain but bounded dwell-time. Process regulation, especially disturbance rejection, is critical to the performance of these advanced systems. However, a method to guarantee disturbance rejection has not been developed. The objective of this study is to develop an $H_{\mathrm{\infty }}$ performance analysis method for APPLSs, building on which an algorithm to synthesize practical $H_{\mathrm{\infty }}$ controllers is proposed. As an application, the developed methods are demonstrated with an advanced manufacturing system – roll-to-roll (R2R) dry transfer of two-dimensional materials and printed flexible electronics. Experimental results show that the proposed method enables a less conservative and much better performing $H_{\mathrm{\infty }}$ controller compared with a baseline $H_{\mathrm{\infty }}$ controller that does not account for the uncertain system switching structure.