Robust impact angle constraints guidance law with autopilot lag and acceleration saturation consideration

Abstract

In this paper, for the three-dimensional terminal guidance problem of a missile intercepting a manoeuvring target, a robust continuous guidance law with impact angle constraints in the presence of both an acceleration saturation constraint and a second-order-lag autopilot is developed. First, based on non-singular fast terminal sliding mode and adaptive control, a step-by-step backstepping method is used to design the guidance law. In the process of guidance law design, with the use of a finite-time control technique, virtual control laws are developed, a tracking differentiator is used to eliminate the ‘explosion of complexity’ problem inherent in the traditional backstepping method, and an additional system is constructed to deal with the acceleration saturation problem; its states are used for guidance law design and stability analysis. Moreover, the target acceleration is considered bounded disturbance, but the upper bound is not required to be known in advance, whereas the upper bound is estimated online by a designed adaptive law. Next, finite-time stability of the guidance system is strictly proved by using a Lyapunov method. Finally, numerical simulations are presented to demonstrate the excellent guidance performances of the proposed guidance law in terms of accuracy and efficiency.

Integrated Guidance and Control with Input Saturation and Impact Angle Constraint

“…Step 1. Select the following nonsingular terminal sliding surface with impact angle constraint [28] as…”

A Novel Guidance Law for Intercepting a Highly Maneuvering Target

“…With the aim of successfully intercepting maneuvering targets, many advanced modern robust guidance law algorithms have been employed, such as the nonlinear H ∞ guidance law [7], the adaptive guidance law [8], the differential game guidance law [9], the L 2 gain guidance law [10], and the optimal guidance law [11]. Compared with the abovementioned robust guidance laws, the sliding mode guidance law [12,13] appears as the most widespread one on account of its simple design process and good robustness to external disturbances [14]. However, the traditional sliding mode guidance law can only achieve asymptotic convergence in an infinite time, because the sliding mode manifold is a linear function [15].…”

Adaptive Super-Twisting Algorithm-Based Nonsingular Terminal Sliding Mode Guidance Law

“…For the disturbance problems such as target maneuvering and system disturbance, there are currently three methods for processing most documents: (1) designing the disturbance observer to estimate the disturbance in real time and online [13,14]; (2) designing the adaptive law to estimate the upper bound of disturbance [15,16]; and (3) using the robustness of the sliding mode control to resist interference. ese methods need to introduce symbolic function terms which will make the control quantity discontinuous and easy to cause the chattering phenomenon.…”