Adaptive finite-time command filtered control for switched nonlinear
systems with input quantization and output constraints
Abstract
This article considers the problem of finite-time command filtered
control for switched nonlinear systems with input quantization and
output constraints. The unmeasurable state is estimated by designing a
switched state observer. During the design process, to overcome the
chattering problem effectively, the hysteresis quantization is designed
as two bounded nonlinear functions. Furthermore, in order to restrict
the output to an expected range, the barrier Lyapunov function (BLF)
approach is introduced. The “explosion of complexity” (EOC) and the
error compensation problems in the backstepping design are solved by
using a finite-time command filtered (FTCF) approach. A first-order
Levant differentiator (FLD) is used instead of the general command
filter in this paper, which cannot only filter the intermediate signals
accurately to get the differential signals, but also ensure the
finite-time stability of the filter. Stability of the closed-loop system
in the sense of semi-global practical finite-time stability (SGPFS) is
proved by exploring a multiple Lyapunov functions approach. Finally, a
simulation example is provided to verify the validity of the presented
control method.