Research On Adaptive All-course Guidance For Boost-Glide Vehicles

Due to the excellent performance of ballistic characteristic and maneuver capability,the boost-glide vehicle has become a popular research topic in aerospace field.This dissertation study the adaptive all-course guidance.Based on the analyses of the ballistic characteristics and guidance missions in different flight phases,some key problems including non-programmed boosting guidance,adaptive gliding guidance independent of the standard trajectory and the three-dimensional robust guidance considering maneuver penetration are studied.A novel non-programmed boosting guidance with low ballistic and multiple constraints is studied for multistage solid booster.1)The scheme of angle-of-attack to realize ballistic turn is designed,in which the guidance parameters are calculated according to the terminal constraints using Newton iteration.2)The guidance model is constructed under ballistic frame,and the optimal control with performance index of minimum energy consumption is employed to design adaptive guidance law.3)To achieve large-scale modification of terminal velocity magnitude,the RPM is introduced to analyze the control capability and design the allocation strategy of excess energy in different stages,and then the velocity is controlled accurately through predictor-corrector.This algorithm,which is independent of standard flight program,has sufficient flexibility and robustness for different missions and large deviations.Based on quasi-equilibrium glide condition(QEGC),a multi-constrained optimal guidance algorithm and a predictor-corrector to meet velocity constraint are proposed.1)It employs line-of-sight(LOS)angle to describe the relative location relationship between flight path and no-fly zones,and proposes boundaries selection algorithm for each no-fly zone.2)The guidance models are constructed based on QEGC,and the optimal guidance is designed in longitudinal and lateral directions to achieve the guidance goal.3)The influences on terminal velocity of different forces are analyzed,and an analytical predictor-corrector algorithm is developed to control the velocity magnitude.In addition,it designs that velocity control is only carried in the later period to ensure control accuracy and the realization of optimal guidance.The proposed method need not to design the standard trajectory,and can achieve the guidance goal with minimum energy consumption adaptively.Independent of QEGC,a novel robust adaptive gliding guidance strategy via online estimation of aerodynamic coefficient is developed.1)The longitudinal altitude control model is founded and a hierarchy-structured guidance strategy is proposed to satisfy terminal altitude and flight-path angle constraints,while the lateral optimal guidance law is utilized to control the vehicle within the instantaneous firing plane.2)The terminal velocity is predicted using lift-drag ratio,and a novel corrector is designed to coordinate the consumption of residual energy and adaptive guidance.3)It builds the aerodynamic models and employs EKF to estimate the unknown parameters which can be adopted to calculate angle-of-attack.The proposed strategy can realize guidance goal without QEGC adaptively,and the robustness can be also improved with the help of online estimation of aerodynamic coefficients by EKF.The three-dimensional(3D)model of relative motion is constructed,and the robust guidance law is proposed based on H_?filter and H_?control.1)Complete three-dimensional relative motion model is established and the coupling coefficient is introduced to describe the influence character between the longitudinal and lateral motions.2)With the 3D model,H_?filter is introduced to eliminate the measurement noises of LOS angles and estimate the angular rates.Furthermore,H_?robust control is well employed to design guidance law,in which the filtered information is used to generate guidance commands.The above researches demonstrate that the 3D model can describe the coupling character of diving motion more adequately,and integrated usage of H_?filter and H_?control can meet the guidance goal accurately and robustly.Considering the terminal guidance accuracy in dive phase,a novel algorithm of diving maneuver realization and an optimal maneuver strategy are investigated.1)The maneuver trajectory which can satisfy both the impact point and angle constraints is developed,and sliding mode control is employed to design the tracker.2)With the above 3D equation,the maneuver control model is constructed through adding maneuver control item to the guidance law.Then,an integrated performance index consists of overload and energy consumption is designed,and optimal control is employed to obtain optimal maneuver strategy when the encounter time determined and undetermined,respectively.3)The performance index and suboptimal strategy are reconstructed to deal with the control capability constraint and the influence on guidance accuracy caused by maneuvering flight.In addition,the penetration capability is analyzed and the optimal maneuver is realized as well.This dissertation expands the research domain of adaptive all-course guidance and panatration of boost glide vehicles.The obtained findings consider the real application requirements fully,and can offer references for the developments of future launch vehicle,endo-atmospheric glider,reentry maneuvering warhead,etc.