The attitude stabilization and trajectory tracking of reentry vehicle via variable-structure based control method

摘要

Some variable-structure-based control methods are presented to the attitude stabilization and trajectory tracking of a reentry vehicle. ^The reentry vehicle is a strongly nonlinear plant which needs three attitude-angle stabilization in the first phase of reentry with the pertubations of aerodynamics parameters, and flight trajectory tracking while keeping the velocity and orbit angle stable at the second phase of reentry. ^We present a variable structure predictive method to the attitude stabilization, while the method can keep attitude angle decoupling tracking and also trade off the control power and performance. ^Simulation shows the closed loop system performance with the perturbations of aerodynamics parameters. ^To the problem of trajectory tracking, we present a PD (proportional + differential) algorithm combined with the variable structure method. ^While, in the inner loop, a variable structure method can be used for linearization and stabilization of velocity and orbit angle, in the outer loop the PD algorithm can guarantee the desired trajectory tracking. ^(Author)