Sliding mode control with unidirectional auxiliary surfaces for Gun-launched UAV

In this paper, the sliding mode control with uni-directional auxiliary surface (UAS-SMC) is proposed for Gun-launched UAV with chattering alleviation and attenuation. The necessary definitions in UAS-SMC method is given to show the detailed information of this method. And relationship between UAS-SMC and traditional SMC method is presented to clearly understand the UAS-SMC theory. Then, a discontinuous UAS-SMC controller is designed to solve the tracking problem of Gun-launched UAV. The simulation results are given to illustrate the performance of UAS-SMC controller.

I. Introduction

Sliding mode control (SMC) is one of well-known nonsmooth control methods, which provides an effective tool for rejecting matched uncertainties/disturbances. Therefore, this method is widely accepted in many applications, see, e.g.[1]–[3]. However, the main disadvantage of this method is perceived as chattering phenomenon. It is harmful because this phenomenon leads to low control accuracy and high wear of moving mechanical parts, which has wider application of the sliding mode control strategy.