Guidance Design For The Interception Of Hypersonic Boost Glide Vehicles

With the rapid development of hypersonic vehicle technologies,the weaponization process of the testing programs is also accelerating.In the foreseeable future,the hypersonic weapons will definitely become a major threat in the warfare.Hypersonic Boost Glide Vehicle(HBGV),as a typical hypersonic vehicle,has the following main features: 1)It can perform penetration policies/maneuvers autonomously;2)It can glide in the atmosphere for a long time with its high Lift to Drag ratio;3)It can maintain its hypersonic speed during the whole reentry stage;4)The maximum available overload of the interceptor is limited due to the thin air of the nearspace.To deal with the above problems,existing interception systems lack of proven techniques and approaches.This paper is going to focus on the main characteristics and difficulties of the interception of HBGV from three main aspects: the guidance information support,the midterm guidance law design and the terminal guidance law design.The main results are as the following:1)This paper set up a new HBGV model augmented with presumed unknown parameters dynamic,and this augmented model is then used in the nonlinear Kalman filter to identify the unknown parameters of the true HBGV model.With the identified parameters,the augmented model is then used to predict the HBGV trajectory.Meantime,the Predict Interception Point(PIP)of the midterm interception is estimated and then provided to the midterm guidance law.The prediction and estimation of the PIP largely alleviate the long range HBGV interception problem.2)In the terminal phase interception,a High Order Sliding Mode Disturbance Observer(HOSMDO)is designed,and the stability proof is provided using Lyapunov stability theorem.By using the HOSMDO,the interceptor can estimate the HBGV maneuvering overload by using onboard sensors,and the HBGV maneuvering information will facilitate the terminal guidance.3)In the midterm guidance law design part,three kinds of requirements need to be satisfied at the same time.First,the terminal position of the interceptor must be the same as required;Secondly,the terminal path angle of the interceptor must be the same as required. Thirdly,the state of the interceptor during all the midterm phase is constrained.To tackle with this problem,a state-constrained Model Predictive Static Program method is proposed.In this method,a slack variable is introduced to incorporate the state constraints into the dynamic model.As a result,a midterm guidance law which can satisfy heat rate constraints,terminal position and angle constraints is proposed.4)In the terminal guidance law design,to achieve a high precision interception against an evasion target by using limited overload commands,this paper established a Nonlinear Continuous-Time Differential Game(NCTDG)problem model to descript the problem.As the analytical solution of the NCTDG problem is not feasible,Adaptive/Approximate Dynamic Programming(ADP)is introduced to give a numerical solution.By using the ADP method,the optimal Value Function of the NCTDG is approximated with a Critic Neural Network(CNN).Value Iteration method is used to revise the CNN.The converged CNN is then to calculate the optimal policies which is the optimal guidance command of the interceptor.5)To demonstrate the effectiveness of the proposed method,a comprehensive numerical simulation is provided.Guidance information supporting method,midterm guidance method,and terminal guidance method are all tested in the simulation.Furthermore,the analysis of some key interception parameters design is also given,which is important to understand the interception system design.