A systematic robust polytopic framework for control co-design

Contemporary technological systems increasingly require integrated plant and controller design to ensure robust closed-loop performance. Control co-design addresses this challenge by simultaneously optimizing plant and controller parameters within a unified framework. This article proposes a robust control co-design methodology based on polytopic H∞ optimization for linear systems. The approach employs a two-level optimization strategy that guarantees closed-loop stability throughout the entire design process, from plant parameter selection to controller synthesis. The proposed framework provides a systematic and reusable reference for robust co-design problems subject to parametric uncertainty. The effectiveness of the method is demonstrated through an automotive active suspension system, where the proposed approach achieves improved closed-loop performance compared to conventional sequential plant-controller design strategies.