通过GPI观测器和集成滑模控制实现运载火箭的鲁棒容错控制

ROBUST FAULT-TOLERANT CONTROL OF LAUNCH VEHICLE VIA GPI

OBSERVER AND INTEGRAL SLIDING MODE CONTROL

Dang-Jun Zhao, Yong-Ji Wang, Lei Liu, and Zhi-Shen Wang

ABSTRACT

A robust fault-tolerant attitude control scheme is proposed for a launch vehicle (LV) in the presence of unknown external disturbances,

mismodeling dynamics, actuator faults, and actuator’s constraints. The input-output representation is employed to describe the rotational

dynamics of LV rendering three independently decoupled second order single-input-single-output (SISO) systems. In the differential

algebraic framework, general proportional integral (GPI) observers are used for the estimations of the states and of the generalized

disturbances, which include internal perturbations, external disturbances, and unknown actuator failures. In order to avoid the defects of the

I. INTRODUCTION

Recently, many countries have focused on building heavy

lifting launch vehicles (HLLV) in order to facilitate their deep

space explorations, such as the Ares series of NASA, the Ariane

series of the European Space Agency, and the Long March series

of China, etc. HLLV is aerodynamically unstable, structurely

flexible, and strongly nonlinear, rendering a great challenge for

the design of ascent flight control systems. The main challenge is

to guarantee high performance in the presence of perturbations,

disturbances, mismodeling dynamics, and actuator faults, thus a

nique is not very robust when facing a large deviation from the

nominal trajectory or system uncertainties. Consequently, many

advanced guidance and control techniques have been developed

for dealing with uncertainties and disturbances, such as, sliding

mode control [1], neural adaptive control [2], nonparametric

adaptive control [3], etc. However, all of these methods

mentioned above have not considered the case of actuator faults,

thus the scarcity of reliability.

In order to enhance the reliability of flight control systems,

a great number of investigations have been made (see two litera-

[6]. For passive FTC schemes, in [7] an FTC controller was

proposed based on dynamics inversion and time delay for attitude

tracking of a rigid satellite; an indirect adaptive fault scheme was

considered in [8] for a spacecraft attitude tracking problem under

thruster faults; in [9], three implicit estimation filters and an

attitude controller derived from the back-stepping technique were

employed in FTC design of spacecraft; an LMI based FTC

control method appeared in [10] for the tracking control of linear

parameter varying systems. Although the aforementioned control

methods have made splendid contributions, there are still some

nique. In this brief paper, the actuator faults mainly refer to the

mechanism deadlock, while the thrust loss is not examined. The

nonlinear multiple-input-multiple-output (MIMO) system of LV

is divided into three independent second order single-input-

single-output (SISO) systems in the framework of differential

algebra originated by Fliess [13]. The disturbances, mismodeling

dynamics, and actuator faults are treated as a generalized

2012.

(60975058), the Nature Science Foundation of Hubei Province (2010CDB01904) and

the 2010 Spaceflight Support Foundation.

© 2012 John Wiley and Sons Asia Pte Ltd and Chinese Automatic Control Society