Study of discontinuous sliding mode observers for unmanned aircraft system

Abstract

Identification, observation and control of systems under uncertainties/perturbations is a major research topic in modern control engineering. In a control system where no measurement noise or no uncertainties are present, continuous observers are able to converge asymptotically to the actual state. If uncertainties are present, they do not converge. To achieve exact and finite time convergence in the presence of uncertainties we design discontinuous sliding mode observers. In this paper four types of observers are discussed for unmanned aircraft system namely linear observer (LO), sliding mode observer (SMO), super twisting observer (STO) and generalized super twisting observer (GSTO).