Journal of Systems Engineering and Electronics ›› 2020, Vol. 31 ›› Issue (4): 815-825.doi: 10.23919/JSEE.2020.000025

• Control Theory and Application • Previous Articles     Next Articles

Extended state observer based smooth switching control for tilt-rotor aircraft

Yiru ZOU1(), Chunsheng LIU1,*(), Ke LU1,2()   

  1. 1 School of Automation Engineering, Nanjing University of Aeronautics and Astronautics, Nanjing 211100, China
    2 Science & Technology on Rotorcraft Aeromechanics Laboratory, China Helicopter Research and Development Institute, Jingdezhen 333001, China
  • Received:2019-03-22 Online:2020-08-25 Published:2020-08-25
  • Contact: Chunsheng LIU E-mail:zouyiru427@163.com;liuchsh@nuaa.edu.cn;looknuaa@163.com
  • About author:ZOU Yiru was born in 1994. She is a master candidate in navigation, guidance and control in Nanjing University of Aeronautics and Astronautics. Her research interests are flight control, especially V/STOL aircraft control, switching control and active disturbance rejection control. E-mail: zouyiru427@163.com|LIU Chunsheng was born in 1955. She is a Ph.D. and a professor in Nanjing University of Aeronautics and Astronautics. Her research interests are adaptive robust control of nonlinear system, faulttolerant control and intelligent control. E-mail: liuchsh@nuaa.edu.cn|LU Ke was born in 1985. He is a Ph.D. candidate in Nanjing University of Aeronautics and Astronautics and also a senior engineer in China Helicopter Research and Development Institute. His research interests are flight dynamics, flight aerodynamic modeling and flight control. E-mail: looknuaa@163.com
  • Supported by:
    the Aeronautical Science Foundation of China(20175752045);This work was supported by the Aeronautical Science Foundation of China (20175752045)

Abstract:

A tilt-rotor aircraft has three flight modes: helicopter mode, airplane mode and conversion mode. Unlike the traditional aircraft, the tilt-rotor aircraft, which combines the characteristics of helicopters and fixed-wing aircraft, is a complex multi-body system with the violent variation of the aerodynamic parameters. For these characteristics, a new smooth switching control scheme is provided for the tilt-rotor aircraft. First, the reference commands for airspeed and nacelle angles are calculated by analyzing the conversion corridor and the conversion path. Subsequently, based on the finite-time switching theorem, an average dwell time condition is designed to guarantee the stability in the switching process. Besides, considering the state vibrations and bumps may appear in switching points, the fuzzy weighted logic is employed to improve the system transient performance. For disturbance rejection, three extended state observers are designed separately to estimate the disturbances in the switched systems. Compared with the traditional auto disturbance rejection control and proportion integration differentiation control, this method overcomes the conservatism of wasting the whole model information. The control performances of robustness and smoothness are verified with simulation, which shows that the new smooth switching control scheme is more targeted and superior than the traditional design method.

Key words: tilt-rotor aircraft, switching control, extended state observer (ESO), smooth switching