Fixed-Time Convergent Guidance Law with Impact Angle Control

Zhongtao Cheng,Bo Wang,Lei Liu,Hao Wu,Yongji Wang

doi:10.1155/2020/5019689

Zhongtao Cheng, Bo Wang + Show 3 more

Open Access

https://doi.org/10.1155/2020/5019689

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Abstract

The existing convergence control guidance laws are designed via the Lyapunov asymptotic stability theory or finite-time stability theory. However, guidance law based on the Lyapunov asymptotic stability theory would lead the states to zero only as time approaches infinity, which is imperfect theory. The convergence time for guidance laws based on finite-time stable theory is dependent on the initial states. A fixed-time convergent guidance law with impact angle control is proposed in this paper. The proposed guidance law consists of two parts. One is the heading error angle shaping term, and the other is the bias term to achieve the desired impact angle. The guidance command is continuous during the engagement without utilizing the switching logics. Unlike the existing guidance law in the literature, the fixed-time stability theory is utilized to ensure the impact angle error to converge to zero before the interception. Furthermore, the convergence rate is merely related to control parameters. Simulations are carried out to illustrate the effectiveness of the proposed guidance law.

Highlights

In the design of the missile guidance system, the primary objective is to reduce the relative range and achieve zero miss-distance attacks
Primitive guidance laws that only achieve the primary objective cannot accommodate to modern war
A recent Lyapunov stability theory-based guidance law was found in [14], the candidate function was proposed to reduce the heading error angle, and a two-stage impact angle control guidance (IACG) was proposed for hitting the target in all aspects

Summary

Introduction

In the design of the missile guidance system, the primary objective is to reduce the relative range and achieve zero miss-distance attacks. A recent Lyapunov stability theory-based guidance law was found in [14], the candidate function was proposed to reduce the heading error angle, and a two-stage IACG was proposed for hitting the target in all aspects. In [16], a finite-time convergent IACG based on the nonsingular terminal sliding mode control (NTSMT) method was proposed, and the resulting guidance law can hit the target with a desired impact angle. Another finite-time convergent guidance law was found in [17].

Fixed-Time Stability Theory of a Nonlinear System

Problem Statement and Guidance Law Design

Simulations

Conclusion