In order to achieve high-precision trajectory tracking of hypersonic vehicles， a trajectory tracking algorithm for highly maneuverable targets combining moving horizon estimation and an interactive multi-model （IMM） algorithm was proposed. Firstly， the motion model and measurement model of the glide segment of the hypersonic vehicle under the half-velocity system were given. Then， the moving horizon estimation method was used to transform the state estimation problem into a constrained optimization problem， and the physical constraints of the glide segment of the flight vehicle were fully considered. On this basis， in order to cope with the different maneuver modes of the target， a model set was established to approximate it with the help of the IMM algorithm. Finally， the algorithm was verified under unchanged and mutated maneuver modes. The results show that the new algorithm adopts parallel estimation of multiple models， and the model probability is adjusted in real time for fusion output， which can effectively avoid the mismatch of the target tracking model and significantly improve the trajectory tracking accuracy of highly maneuverable targets such as hypersonic vehicles.

To address the drag acceleration profile design challenge during the gliding trajectory guidance of hypersonic vehicles， this paper proposes an improved method for designing the drag acceleration profile. To enhance the gliding range of the aircraft and improve flight state parameters， the paper designs a novel drag acceleration profile in the form of a quadratic function with the reciprocal of energy as the independent variable. The profile shape is adjusted by changing the drag acceleration values at the midpoint， satisfying various constraints of hypersonic flight. Simulation results indicate that， in comparison to the traditional quadratic drag acceleration profile， the proposed profile significantly increases the maximum gliding distance and improves flight state parameters， enabling the aircraft to complete flying missions around no-fly zones.

When flexible spacecraft operates， disturbances such as the swaying of liquid fuel and gravity gradients cause the spacecraft system to exhibit strong nonlinearity and coupling characteristics. Thus， controlling its attitude deflection has always been a challenging problem. To solve this issue， this paper designs a H_∞ state feedback controller. The integrated disturbance term in the dynamic model of the flexible spacecraft is redefined， and combined with the kinematic model， the mathematical expression of the flexible spacecraft is formulated. The mathematical model of the flexible spacecraft is transformed into an H_{\mathrm{\infty }} state feedback control mathematical model. The theoretical applicability of the controller is demonstrated by mathematical theory. The mathematical model of the flexible spacecraft under H_{\mathrm{\infty }} state feedback control is simulated by simulation software. The results show that the designed H_{\mathrm{\infty }} state feedback controller can effectively achieve attitude stabilization and vibration suppression of flexible spacecraft， showing practical value.