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A combination BTT control mode with the single moving mass and differential aileron is proposed in this paper for some engineering problems of long-range reentry maneuverable vehicle controlled by only one actuator. This control mode can not only avoid the elevator and rudder ablation to improve the efficiency of attitude control, but also reduce the quantity of moving mass actuator. According to the dynamics model of the proposed control mode, the extended state observer is used to estimate the states of system, the external disturbances and parameter uncertainties disturbance based on an integrated manner, then the roll channel control system is designed by using LQR controller. Lastly, the simulation results are presented to demonstrate the efficacy of the extended state observer in estimation of the uncertainties and states, and the proposed design is robust to the disturbances caused by the moving mass lateral movement and the asymmetric ablation of vehicle, parameter uncertainties, unmodeled dynamics.

Considering the path constraints, control constraints and initial/terminal states constraints, optimal projectile state and trajectory of reentry body are designed based on hp-adaptive pseudospectral method to achieve maximum range. Path constraints include normal overload constraint, dynamic pressure constraint and heating rate constraint; control constraints include angle of attack constraint and bank angle constraint; initial/terminal states constraints include altitude constraint, velocity constraint and flight path angle constraint. In face of the fact that the range of optimal control solution resulted from pseudospectral method may be unsmooth, virtual control variables (second derivatives of the angle of attack and bank angle) are proposed in the optimization, while the angle of attack and bank angle are treated as the virtual state variables to guarantee the smoothness of the optimal control solution. The validity of hp-adaptive pseudospectral method in dealing with nonlinear, multi-constrained, multi-variable optimization problems is verified by simulation, and the consistency between the solution obtained and the first-order necessary conditions for optimality of indirect method is confirmed using the costate and Hamiltonian.

Directional sensitivity and amplitude-phase consistent are the key factor that can affect the stability and precision of tracking targets for pulse instrumentation radar, so they need to be calibrated. For the shortcomings of traditional tower calibration, the towerless calibration method based on offset dipole compensation is proposed. And the feasibility is checked according to analysis of offset dipole compensation. The towerless calibrating system is designed and put into use in tracking a certain satellite. The tracking experiment indicates that the calibration result using towerless is superior to tower, and the system satisfies the demand of pulse instrumentation radar.

With respect to hypersonic re-entry vehicle, by applying the Newton-Euler's method, the six-degrees of freedom(6-DOF) dynamical equations of moving mass for a re-entry vehicle are derived and the control mechanism is analyzed according to the dynamical equations. Under the environment of Matlab, the 6-DOF trajectory simulation is presented based on the dynamical equations considering the earth's rotation and non-spherosomes factors, the cross-range and down-range of the impact point cause by lateral movement of the moving masses are computed by simulation and the results validate the feasibility of moving mass control.

The new predictive guidance law for reentry vehicle is presented in this paper. The proposed approach is based on the fact that lateral forces are formed to a plane perpendicular to the reentry vehicle velocity. In particular, the nominal ground location is defined as the ground location generated by the zero lift trajectory, the virtual displacement is defined as the small changes of the nominal ground location, this changes is caused by any instantaneous lateral force at the beginning of the trajectory. The optimal direction of the lateral force is searched by the solution to the optimal virtual displacement, in which case the virtual displacement is pointing to the target ground location. The analytical solution to the reentry trajectory and the linear quadratic gauss (LQG) method are used in this guidance method. The simulation results show that the effectiveness of proposed method.