Stability Of Guidance System Research Articles

Qualitative indicator-based guidance scheme for bank-to-turn missiles against couplings and maneuvering targets

This paper deals with the design of a three-dimensional (3-D) robust guidance scheme for bank-to-turn (BTT) missiles against couplings and target maneuver. Firstly, the missile-target coupled relative dynamics are established. Then, a qualitative indicator (QI) is designed based on Lyapunov stability theory for both coupling and target maneuver terms to indicate whether they strengthen or weaken the system stability. Moreover, a nonlinear disturbance observer (NDOB) with fixed-time convergence is introduced to estimate the unknown target acceleration. A robust guidance scheme is proposed by synthesizing QI, sliding mode control (SMC) and NDOB. The stability of guidance system is proven via Lyapunov stability theory. Finally, numerical simulations are executed to validate the effectiveness of proposed guidance scheme.

Influence of Seeker Disturbance Rejection and Radome Error on the Lyapunov Stability of Guidance Systems

This study analyzes the effects of disturbance rejection and radome error on the stability of guidance systems. First, disturbance rejection rate transfer function (DRRTF) models are established. Second, the Lyapunov stability of a proportional navigation guidance system is proposed. The passivity theorems are introduced for the analysis of the Lyapunov stability of the nonlinear time-varying system. Finally, the influence of the different DRRTF models on the stability of the guidance system is analyzed by mathematical simulations. The simulation results indicate that the stable boundary of the guidance system varies and its tolerance to disturbance differs significantly for various disturbance torque types and radome slope.

Effect of seeker disturbance rejection rate on performance of optimal guidance laws with terminal impact angle constraint

In order to study the effect of seeker disturbance rejection rate on performance of optimal guidance law, based on guidance law with terminal impact angle(GLTIA) and extended guidance law with terminal impact angle(EGLIA), the regularization of strapdown seeker disturbance rejection rate on the stability of guidance system was studied. Using adjoint method the miss distance of GLTIA and EGLIA were analyzed. The results show that the stable domain of guidance system is larger when strapdown seeker parasitic loop is negative feedback than positive feedback, the stability will reduce when the value of disturbance rejection rate gets bigger. Though EGLIA has more excellent guidance performance than GLTIA, but the influence of a parasitic loop of seeker disturbance rejection rate will be more serious, the sufferable value of seeker disturbance rejection rate for EGLIA is about 2.5%, and the GLTIA is about 3.5%. In the practical application, if the guidance law would work with advanced performance, the value of seeker disturbance rejection rate should be much stricter to reduce the effect of parasitic loop.

Study on Autopilot Dynamics with Robust Guidance Law and Terminal Constraint in Mechanical Engineering

A new nonlinear robust guidance law was proposed by considering autopilot dynamics. Firstly, the mathematic model was built according to relationship between target and missile in vertical plane, by introducing the one-order dynamics of autopilot in Mechanical Engineering. Secondly, the nonlinear terminal guidance was obtained by applying the H∞ control theory under the performance index of minimizing the terminal angular constraint tracking error and control energy, and the asymptotic stability of guidance system was strictly proven by Lyapunov stability theory avoiding the estimation of the time-to-go. Finally, an illustrative example was given to show that the guidance law was more robust and both the impact angle and guidance precision were met in the case of no any target information.