Hybrid Trajectory Optimization Method and Tracking Guidance for Variable-Sweep Missiles

Zhifang Wei,Yang Cheng,Senlin Liu,Xiangxiang Guo,Filippo Cacace

doi:10.1155/2021/6669618

Zhifang Wei, Yang Cheng + Show 3 more

Open Access

https://doi.org/10.1155/2021/6669618

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Abstract

In this paper, an offline hybrid trajectory optimization approach is proposed for variable-sweep missiles to explore the superiority in the diving phase. Aiming at the maximal terminal velocity with the impact angle constraint, the trajectory optimization model is formulated under multiple constraints, and the aerodynamic analysis in different sweep angles is discussed. Unlike only the attack angle used for the optimization process traditionally, the two-variable optimization scheme on both the attack angle and sweep angle is investigated for variable-sweep missiles. Then, the trajectory optimization problem is transformed into the nonlinear programming problem via a hybrid optimization strategy combining the Gauss pseudospectral method and direct shooting method to obtain the high precision and fast convergence solution. Finally, to verify the feasibility of the optimal trajectory under uncertainties, the tracking guidance law is designed on basis of the gain scheduled linear quadratic regulator control. Numerical simulation results reveal not only of the proposed hybrid optimization strategy but also of the superiority of variable-sweep missiles compared with traditional missiles.

Highlights

Missiles are widely used in fiercely confronted environment and increasingly complex modern warfare for high guidance accuracy, strong penetration capability, and good maneuverability [1]
Traditional missiles adopt the fixed aerodynamic configurations, which lead to the limited flight performances. us, the morphing wing technology has been brought up in an effort to offer the well-matched aerodynamic characteristics in different flight states by means of changing the wing shape adaptively, such as stretching the wings to obtain the large lift-to-drag ratio in the cruise phase and shrinking the wings to reduce the drag coefficient in the diving phase [2, 3]
Mathematical Problems in Engineering missiles are quite limited. erefore, to explore the superiority of the variable-sweep missile, the investigation of this paper mainly focuses on its trajectory optimization design

Summary

Introduction

Missiles are widely used in fiercely confronted environment and increasingly complex modern warfare for high guidance accuracy, strong penetration capability, and good maneuverability [1]. Different from other direct methods, the Gauss pseudospectral method (GPM) has obtained great attention for fast convergence, global optimization, and extensive applications in the aerospace field recently by means of approximating the control and state variables with polynomials [19,20,21,22]. Motivated by the requirements of the trajectory optimization for the variable-sweep missiles with complex trajectory characteristics, an offline hybrid sequential trajectory optimization strategy combining the GPM and DSM is proposed to obtain the high precision and fast convergence solution in this paper. Numerical simulation results show the effectiveness of the proposed hybrid optimization strategy and the superiority of variable-sweep missiles compared with the traditional missiles.

Problem Formulation

Hybrid Optimization Strategy for Trajectory Optimization

Gain Scheduled LQR Controller for Tracking Guidance

Numerical Simulations

Conclusions