Back-stepping active disturbance rejection control design for integrated missile guidance and control system via reduced-order ESO

This paper proposes a novel composite integrated guidance and control (IGC) law for missile intercepting against unknown maneuvering target with multiple uncertainties and control constraint. First, by using back-stepping technique, the proposed IGC law design is separated into guidance loop and control loop. The unknown target maneuvers and variations of aerodynamics parameters in guidance and control loop are viewed as uncertainties, which are estimated and compensated by designed model-assisted reduced-order extended state observer (ESO). Second, based on the principle of active disturbance rejection control (ADRC), enhanced feedback linearization (FL) based control law is implemented for the IGC model using the estimates generated by reduced-order ESO. In addition, performance analysis and comparisons between ESO and reduced-order ESO are examined. Nonlinear tracking differentiator is employed to construct the derivative of virtual control command in the control loop. Third, the closed-loop stability for the considered system is established. Finally, the effectiveness of the proposed IGC law in enhanced interception performance such as smooth interception course, improved robustness against multiple uncertainties as well as reduced control consumption during initial phase are demonstrated through simulations. The structure of the proposed novel hierarchical IGC scheme for missile. [Display omitted] •The results presented are first attempts to accomplish IGC design with actual missile model and multiple disturbances considered.•Reduced-order extended order observer (ESO) is constructed to estimate the uncertainties in guidance and control loop.•Nonlinear tracking differentiator is employed rather than dynamics surface technique used in the conventional back-stepping method, which can substantially alleviates the peaking phenomenon in control.•Comparisons between the performance of ESO and reduced-order ESO are firstly examined.•Extensive simulations are given to validate the superiority of the proposed approach over the existing methods.