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A new nonlinear control algorithm of combining dynamic inversion , wavelet net and sliding mode control has been developed. The nonlinear dynamic theory is used to approximate linearization of the nonlinear system , the system dynamic inversion error is compensated by wavelet net which is capable of online learning. The adaptive weights adjustment rule is derived by using lyapunov stability theory, and the system robustness is guaranteed by using sliding mode control and robustness control. The presented nonlinear control algorithm is applied to one STT missile control system, The simulation results show the proposed algorithm can eliminate the influence brought by disturbance availably, raise the precision of missile overload control system response.

Based on multilayer neural networks, feedback linearization technology, and backstepping design method, a novel robust adaptive control design method is proposed for one hypersonic vehicle(HSV) uncertain MIMO nonaffine block control system. Multilayer neural networks are used to identify the nonlinear uncertainties of the system. A continuous robust term is adopt to minify the influence of the multilayer neural networks construction error, the dynamic surface control strategy to eliminate "the explosion of terms" by introducing a series of first order filters to obtain the differentiation of the virtual control inputs. Finally, nonlinear six-degree-of-freedom (6-DOF) numerical simulation results for a HSV model are presented to demonstrate the effectiveness of the proposed method.Index Terms -hypersonic vehicle ,.neural networks ,.dynamic surface ,. backstepping of a 6-DOF HSV model is preformed to verify the effectiveness of the proposed algorithm and the conclusions are given. II. NONLINEAR HSV MODEL WITH UNCERTAINTIESWinged-cone'!' is one of the main investigate objects with its hypersonic mach number and open aerodynamic parameters, but most research is based on its longitudinal channel model. In this paper we finished Winged-cone's three-axes, highly nonlinear model with general set of uncertainties. The nonlinear dynamic equations are given as follows(the full HSV model is given in appendix, and parameters are obtained from literature [1]): Xl »T, (xl'x 2 ) x 2 == h (X 2)+ gI (X 2)X3 + WI (x 2)u We assume that .h ' gI , hI ' J. ' f3 and g2 are unknown and h == hO +4h, gI == gIO +~gI 'h ==ho+~, g2 ==g20 +~g2,hI = h lO +~hI· where flO , gIO , w lO , f20 , g20 are nominal system parameters, the others are uncertainties. The meaning of the symbols used in this paper can be founded in appendix and literature [ 1].The task of the controller is to track the commands signals when aerodynamic model uncertainties exist.Assumption 1: Ignoring the effect of the fin deflection on the aerodynamic force and viewing it as a part of the uncertainties, namely WI (Xl) == 0 . where, (3) q f3 x -r X 2 = [a 6 a 6 r ]T x -[v 1 -

Abslract: In order to solve the mim~tched uncertainties of a class of nonlinear systems,a control method of sliding mode control (SMC) based on the backstepping design is proposed. It introduces SMC in to the last step of backstepping design to modify the backstepping algorithm. This combination not only enables the generalization of the backsteppmg design to be applied to more general nonlinear systems,but also makes the SMC method become effective in solving the mismatched uncertainties. The SMC based on the backstepping design is applied to the flight control system design of an aerodynamic missile. The control system is researched through simulation. The simulation results show the effectiveness of the proposed control method.

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