Semiglobal finite-time trajectory tracking realization for disturbed nonlinear systems via higher-order sliding modes

This paper investigates an alternative nonrecursive finite-time trajectory tracking control methodology for a class of nonlinear systems in the presence of general mismatched disturbances. By integrating a finite-time disturbance feedforward decoupling process via higher-order sliding modes, it is shown that, a novel nonrecursive design framework resulting a simpler controller expression and easier gain tuning mechanism is presented. A new feature is that a quasi-linear inherent nonsmooth control law could be constructed straightforwardly from the system information, which is essentially detached from the determination of a series of virtual controllers. Moreover, by proposing a less ambitious semiglobal tracking control objective, the synthesis procedure can be achieved without restrictive nonlinear growth constraints. Explicit stability analysis is given to ensure the theoretical justification. A numerical example and an application to the speed regulation of permanent magnet synchronous motor are provided to illustrate the simplicity and effectiveness of the proposed nonrecursive control design approach.