16:00 - 17:00
Title: Prescribed-time control
Abstract: In terms of the user’s knowledge about the settling time, non-asymptotic controllers can be divided into three major categories of finite-time, fixed-time, and prescribed-time approaches. In finite-time schemes, it is only known that the system non-asymptotically converges at a finite time that is generally a function of the initial conditions. Fixed-time schemes provide an upper bound for the settling time, independently of initial conditions. However, in prescribed-time control, the settling time is commanded to the system, which means that the user is not only aware of the convergence moment but can arbitrarily specify it just by changing a parameter. It turns out that another interesting feature of prescribed-time controllers, apart from having an adjustable settling time, is their robustness to unknown dynamics for which no global bounds exist.
In this talk, after reviewing the state-of-the-art, some new unpublished results on the differential Riccati equation approaches to prescribed-time control are discussed (LQR and SDRE-based designs), and it is shown how they can be used for the stabilization of (partially) unknown nonlinear systems.