外文翻譯-機(jī)械模具自動化【期刊】三維空間攔截的前置追蹤變結(jié)構(gòu)制導(dǎo)律-外文文獻(xiàn)

1、 Chinese Journal of Aeronautics Chinese Journal of Aeronautics 21(2008) 247-251 www.elsevier.com/locate/cjaHead Pursuit Variable Structure Guidance Law for Three-dimensional Space Interception Ge Lianzheng*, Shen Yi,

2、 Gao Yunfeng, Zhao Lijun Department of Control Science and Engineering, Harbin Institute of Technology, Harbin 150001, China Received 21 September 2007; accepted 25 December 2007 Abstract This article aims to develop a h

3、ead pursuit (HP) guidance law for three-dimensional hypervelocity interception, so that the effect of the perturbation induced by seeker detection can be reduced. On the basis of a novel HP three-dimensional guidance mod

4、el, a nonlinear variable structure guidance law is presented by using Lyapunov stability theory. The guidance law positions the interceptor ahead of the target on its flight trajectory, and the speed of the interceptor i

5、s required to be lower than that of the target. A numerical example of maneuvering ballistic target interception verifies the rightness of the guidance model and the effectiveness of the proposed method. Keywords: head

6、pursuit; three-dimensional guidance model; nonlinear variable structure; Lyapunov stability theory; guidance law 1 Introduction1 In tactical ballistic missile interception, many interceptors employ an infrared seeker to

7、 detect the target. However, the detection precision is often degraded by aerodynamic heating[1]. To solve the aerodynamic ablation problem, a head pursuit (HP) guidance law, which positions the interceptor mi- ssile ahe

8、ad of the target on its flight trajectory to destroy the target, has been developed recently[2]. Using this guidance law, the interceptor can fly in the same direction with the target at a lower speed than that of the ta

9、rget. Compared to a head-on engagement, the low closing speed is achieved with reduced energy requirements. The HP guidance method is further improved in Refs.[3-4], where the relative motion model is separated into two

10、perpendicular channels and the guidance problem can be treated as a planar problem in each of those *Corresponding author. Tel.: +86-451-86418285. E-mail address: gelz@hit.edu.cn channels. Based upon the planar model, a

11、 HP variable structure guidance law is then developed. However, as the actual missile interception occurs in three-dimensional space, a three-dimensional HP guidance method is more useful in practical applications. Vario

12、us classic guidance methods have been examined for implementation of three-dimensional guidance interception since the origination of the three-dimensional pure proportional navigation gui- dance law proposed by Adler[5]

13、. Refs.[6-11] have developed the three-dimensional guidance model and given a guidance law based on Lyapunov sta- bility theory. These guidance laws are only suitable for head-on interception, their interception styles a

14、nd kinematics models are different from the HP guidance method. As an intuitive and robust control technique, the sliding mode variable structure control[12-15] has been utilized in various guidance applications to addre

15、ss highly nonlinear systems Ge Lianzheng et al. / Chinese Journal of Aeronautics 21(2008) 247-251 · 249 · m t 0 0 lim 0, lim 0 r r θ θ → → = =(8) m t 0 0 lim 0, lim 0 r r ? ? → → = =(9) The objective of the HP

16、 guidance law is to bring the interceptor to the point, which is confined by Eqs.(8)-(9). Hence, the interceptor’s lead angles m θ and m ? are required to be proportional to the target’s lead angles relative to LOS:

17、m 1 t m 2 t , n n ? ? θ θ = =(10) where n1 and n2 are the guidance constants. Thus, the relations mentioned earlier can guarantee that θm vanishes with θt, and ?m vanishes with ?t. It is then necessary to find out the re

18、lation between the angular condition defined by Eq.(10) and the inter- ceptor acceleration. 3 HP Variable Structure Guidance Law 3.1 Variable structure control law Considering the nonlinear multiple-input mul- tiple-out

19、put (MIMO) uncertain system 1 2 ( , ) ( , ) ( ) ( , ) ( ) t t t t t = + + X f X g X U g X W ?(11) where n ∈ R Xis the state variable, ( ) p t ∈ R Uthe control variable, and ( , ) t f Xthe uncertain nonlinear item.

20、1( , ) t g Xand 2( , ) t g Xare vector functions, which have suitable dimensions. ( ) t ∈ Ws R is the acceleration disturbance of the target and limited by 0 ( ) t b? < 0 0 V V ? . It is easily checked that = ? =

21、0 0 V X . Hence, the system is asymptotically stable, and the conditions of the sliding mode variable structure control theory are satisfied, thus Lemma 1 holds. 3.2 The design of nonlinear guidance law It follows that t

22、o realize the control law one only needs to know the scope of acceleration of the target, and it can be applied in the course of intercepting the unknown acceleration target. Usually no control is taken in the LOS direct

23、ion, as long as other parameters are kept sliding on the sliding surface. When the target catches the interceptor, the guidance control is completed. The other coupling parameters can be treated as disturbances, so one c

24、an design the guidance law by using the design method[16] of single channel. The authors have design the nonlinear variable control guidance law by using the yaw channel as an example. The aim is to bring the system into

25、 the sliding surface and keep the dynamical charac- teristics of the system. According to Eqs.(11), (13)- (14), the variables are defined as: ( ) u t = m z ais the control variable. t t z w a =is the acceleration of th