Control of a flexible aircraft using a Lyapunov-based switching scheme with a guaranteed stability margin

Abstract

In dynamical systems with significant uncertainties, implementing a verifiable control scheme which guarantees a satisfactory performance is of great importance. In flight control, the parameters of aeroelastic systems change largely within the flight envelope, so a single robust linear controller may not be able to achieve the desired control objectives. One idea to deal with this problem is to partition the uncertain parameter set into smaller subsets and design a linear controller for each subset using robust control design techniques. Monitoring the plant dynamics to determine the best candidate controller can be based on the estimates of the uncertain plant parameters which are obtained by using an online parameter estimator

however, in the absence of persistently exciting signals, there is no guarantee for parameters convergence to the true values, and therefore convergence to the appropriate controller to ensure a desired stability margin cannot be guaranteed. This paper employs a Lyapunov-based switching scheme to control a flexible aircraft whose parameters corresponding to the elastic degree of freedom are uncertain. The scheme ensures convergence to the appropriate controller with a guaranteed margin of stability.