Few results are made on non-affine non-strict feedback nonlinear systems, which is a challenging problem in the control theory. In this paper, a novel control method based on an advanced backstepping and auto disturbance rejection is presented for a class of non-affine non-strict nonlinear feedback systems. The proposed advanced backstepping controller consists of differentiator and extended state observer, which are respectively used to approach the derivative of the virtual control and estimate the unknown part of the system. The framework of the proposed controller is both systematic and simple, and the assumptions have been relaxed. Moreover, the input to state stability analysis shows that the system states can asymptotically converge to an arbitrarily small region of equilibrium point. The simulation studies proved the effectiveness of the proposed design scheme.

In this paper, tracking controller and synchronization controller of the Arneodo chaotic system with uncertain parameters and input saturation are considered. An adaptive tracking control law and an adaptive synchronization control law are proposed based on backstepping and Lyapunov stability theory. The adaptive laws of the unknown parameters are derived by using the Lyapunov stability theory. To handle the effect caused by the input saturation, an auxiliary system is used to compensate the tracking error and synchronization error. The proposed adaptive tracking control and synchronization schemes ensure the effects of tracking and synchronization. Several examples have been detailed to illuminate the design procedure.

A compound control based on active disturbance rejection control (ADRC) scheme and slide mode control (SMC) is proposed to investigate the attitude tracking problem for a spacecraft with modeling uncertainties, external disturbances, actuator failures, and actuator saturations simultaneously. A positive term including control input is separated from the system, and then, the active disturbance rejection concept and the extended state observer (ESO) are applied to deal with the general uncertain item caused by uncertainties, external disturbances, actuator failures, and actuator saturations. The sliding mode surface is designed to transform the attitude tracking problem into attitude stabilization problem. In order to deal with the actuator saturations, a saturation degree coefficient and its corresponding adaptive law are introduced. Compared to other existing references, the proposed scheme does not need to know the structure or upper bound information of the inertial matrix uncertainties and external disturbances. Finally, the stability of the closed-loop system is analyzed by using input to state stability theory. Simulation results are given to verify the effectiveness of the proposed scheme. More importantly, the proposed technique can also be applied to the attitude stabilization of other aircraft, such as the attitude of unmanned aerial vehicle and helicopter in maritime rescue.

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Sea background radiation is influenced by solar radiation, sky background radiation and sea surface emission radiation. On the basis of studying the simple sea radiation model, analyze the influence of atmospheric transmittance and sea background radiation to infrared detector, emphasis on influence of solar, sky and sea surface emission radiation to infrared search in analyze Sea background radiation, emphasis on influence of aerosol to infrared search under troposphere in analyze atmospheric transmittance.