Robust Control Using an Extended H-Infinity Approach: Concepts and Application

Ismaila Tijani, Agus Budiyono


The need to robustify a control system against uncertainty in the plant parameters has been one of the fundamental design objective in the robust control field. One of the elegant approach of achieving this objective involves incorporating the v-gap metric into the well-known H-infinity Loop Shaping Design Procedures (H∞ LSDP). This integrated approach, known as an Extended H-Infinity approach provides an intuitive description of plant parametric uncertainty and as rightly called, extends the conventional H∞ LSDP to effectively handle such problem. Meanwhile, the conceptual formulation of this approach has received less attention in the literature which in turns limits its applications. In this paper, the concepts of the extended H-infinity in terms of mathematical description, problem formulation, design challenges and proposed procedures for practical applications are presented. A practical application to a small scale unmanned helicopter control is provided to demonstrative the effectiveness of the approach in robust control of dynamic system especially to parametric uncertainty.


V-gap; Robust Control; Extended H-Infinity; Parametric Uncertainty

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