Finite‐time trajectory tracking control for entry guidance

Abstract

Summary In this paper, the trajectory tracking guidance problem is investigated for entry vehicle in the presence of uncertainty. First, a robust nonsingular fast terminal sliding mode control law is designed to guarantee the finite‐time tracking performance under uncertainty. Then, to eliminate the need of prior information about uncertainty and mitigate the chattering, a novel adaptive nonsingular fast terminal sliding mode control is proposed by employing adaptive parameter tuning law. Furthermore, with the help of designed adaptation mechanism, the proposed adaptive nonsingular fast terminal sliding mode control can achieve finite‐time convergence of both tracking errors and parameter estimation errors simultaneously. Finally, numerical simulations are given to demonstrate the effectiveness and high‐precision tracking performance of the proposed controllers.

Indirect neural-based finite-time integral sliding mode control for trajectory tracking guidance of Mars entry vehicle

“…Remark 1. Different from the terminal sliding mode surface in Dai and Xia (2015), Zhao et al (2015), Dai et al (2017), Shen et al (2018aShen et al ( , 2018bShen et al ( , 2019, Gong et al (2020), andLong et al (2020) and the integral sliding mode surface based on the homogeneous method in Zhao et al (2016), the proposed finite-time integral sliding mode surface ( 20) is constructed based on the adding a power integrator technique. Benefiting from the new type of finitetime integral sliding mode surface, the finite-time integral sliding mode controller has no singularity problem, which overcomes a major drawback of the conventional terminal sliding mode control.…”

“…Subsequently, Shen et al (2018b) proposed a new compound control method consisting of an adaptive nonsingular terminal sliding mode controller and an extended state observer. In Shen et al (2018aShen et al ( , 2019, several adaptive nonsingular terminal sliding mode control schemes were presented for the Mars entry trajectory tracking with finite-time convergence. Long et al (2020) designed a barrier Lyapunov function based terminal sliding mode controller for the trajectory tracking of Mars entry vehicle with input saturation.…”

Fixed-time attitude tracking control for spacecraft based on a fixed-time extended state observer

“…T . With respect to (21), Λ = 0 if t T * . Then, the error estimation equation ( 22) can be rewritten as follows:…”

“…It is well-known that the conventional SMC may cause the chattering phenomenon. As a result, terminal SMC (TSMC) [19,20] and fast non-singular TSMC (FNTSMC) [21] technologies have been extensively used as the enabling technology to overcome this weakness and achieve better performance compared with the traditional SMC method. It is worth mentioning that these proposed SMC extensions allow ensuring finite-time convergence.…”