67 Sliding Mode Variable Structure Control for UAV Longitudinal Loop

This paper introduces the Sliding Mode Variable Structure Control to UAV flight control system. The principle of the Sliding Mode Control Design is presented. The existence condition and the hitting condition of the error adaptive sliding regime are discussed. By studying the longitudinal attitude stabilization loop, a switching function is proposed to realize an error adaptive variable structure. In order to eliminate the chattering of the sliding regime, a dead zone is utilized to realize the variable structure control of the attitude stabilization. Simulation results show that this technology has the following benefits: high disturbance immunity, high control quality, high accuracy and simple algorithm.