l₁ State Feedback Control of Active Suspension

Abstract

In this paper, the disturbance rejection problem of an automotive active suspension is formulated as an l₁ control problem, that is, the minimization of the effects of disturbances in terms of the l_∞-induced norm. Since l₁ control theory minimizes the maximum possible amplification of signal magnitude, the l₁ controller can specify the maximum magnitude of outputs in the time domain, regardless of the frequency of road disturbances. Shamma's l₁ near-optimal control theory is applied with a certain approximation. To design a simple static full state feedback controller, a nonlinear controller is designed for a linear active suspension model of a quarter vehicle. Finally, satisfactory performances are confirmed by numerical analysis.