The error resources of star sensor, definition of low frequency error (LFE), error analysis and calibration methods are described in this paper. The field of view (FOV) spatial error and thermo elastic error are the main factors in orbital periodic error of star sensor. The LFE of typical star sensor is less than 0.8″ via new methods.

The averaged relative motion equation of elliptic orbit satellite formation is presented based on the averaged analysis method during an orbit period, and two different formation configuration maintaining methods are proposed. The orbit elements difference is used to derive the averaged relative motion equation, and the proposed model can effectively eliminate the periodic movement. Based on the linear recursive equation of mean orbit elements difference, the forecast equation of averaged relative motion is obtained via considering the orbital perturbation. The forecast model can provide valuable information for configuration design and configuration maintaining. Simulation results verify the effectiveness of the proposed formation configuration maintaining methods.

The design of the guidance system for a hypersonic reentry vehicle is presented. The major contributors are discussed, such as aero characteristic, attitude control ability, thermal protective, servo ability, mass, and structure strength. The guidance requirement is needed for early conceptual design. A new approach for guidance overall design is presented. To be appropriate to the vehicle configuration, the guidance law is designed to coordinate the tightly coupled parameters of the vehicle and subsystems.

For a class of multi-body satellites systems with gimbal driver assembly (GDA) and small angle maneuvering antennas, the sequential return difference design method based on the two-input and two-output linear system model is proposed. And the multi-input multi-output(MIMO) controllers which include the pitch attitude control and antenna pointing control are obtained. Moreover, stability analysis of the corresponding closed-loop system is presented by the Nyquist stability criterion. Then the stability margin of the MIMO control system is obtained by calculating the minimum singular value of the system return difference matrix and the minimum singular value of the inverse return difference matrix. The two results are combined to reduce the conservativeness of the stability margin. Finally, numerical simulation results are presented to verify that the proposed controller and the stability margin method are effective.

Design for testability (DFT) is an important approach to improve the manufacturing efficiency and test quality of a system. The hierarchical structure of DFT for AOCS of spacecraft based on 1553B bus architecture is given and the model frame of DFT is built. The technical realization of DFT is also analyzed. The software TEAMS(testability engineering and maintenance system) is used to simulate and evaluate the DFT via an example and the simulation result demonstrates the validity of this method.

A fast and accurate control system of the piezo-based steering mirror is presented in this paper. The closed-loop control system for scanning and tracking is constructed by combining the piezobased steering mirror, voltage amplifier, displacement sensor and realtime control system AD5435. Then, the feedforward-feedback composite control is designed by using the characteristics of hysteretic dynamic in the piezoelectric system. The fast and accurate tracking performance of the piezobased mirror is demonstrated by the closed-loop control experiment, in which the relative root mean square（RMS） errors of the sinusoidal and triangle trajectories at 50Hz are less than 3.6%. The fast and accurate control method presented in this paper is beneficial to the accurate scanning and jitter suppression in the satellite-based optical-mechanical system.

The remote sensing satellite puts forward higher requirements to the rapidity of satellite attitude maneuver ability. This paper presents a satellite attitude maneuver control method based on a theoretical trajectory and gives a detailed on-line description. With large-torque flywheels and the modified angle model based on extended experiments, the satellite attitude agility ability is obtained. Numerical simulations and comparisons are provided to illustrate the effectiveness of the proposed method.

Based on the standard ballistic, an improved longitudinal guidance law for reentry vehicle is proposed, which is deduced from compensation ideas. By using the unknown perturbation function, the longitudinal dynamics equation is described. Based on the equation, a guidance law is designed to adapt the changes of atmospheric parameters. The whole control contains the standard guidance law and adaptive compensation guidance law. The simulation results show that the designed control law can compensate the changes of aerodynamic parameters and atmospheric density.

Detection of space small moving targets in time sequence of space images is a key technique for space-based surveillance, tracking and catalog. To process the mass of multidimensional data from an optical telescope in a timely and computationally efficient fashion, an algorithm is introduced for targets detection and trace acquisition based on neighborhood binary and advanced PHT (probability hough transformation) method. Compared with MTI (moving target indicator) algorithm, the number of positive false and candidate tracks is reduced obviously. Simulation results show that the algorithm is useful for optically detecting moving targets which move in a straight path quickly across many frames of data.

In order to effectively eliminate the vibration of magnetically suspended flywheel(MSFW), the micro-vibration model of a special structure flywheel is built and analyzed. The vibration forces and torques are tested by using micro-vibration plate and data acquisition analysis hardware and software. By analyzing the characteristics of the forces and torques in time domain and frequency domain, their vibration characteristics diagram, i.e. waterfall diagram, shows that the main components of forces in X and Y radial direction are the same frequency components, multiplier frequency components and modal components. The vibration forces in X and Y radial directions are controlled via the open and closed loop adaptive notch filters, and the results are preferable.

By analyzing the orbit data of a long-term running satellite, the evolution laws of infrared earth sensor radiant intensity (IESRI) are concluded for evaluating the performance of infrared earth sensor. The short-term changing of the IESRI depends on the latitude of satellite orbit. The medium-term changing depends on the period of the season of earth. The long-term changing depends on the capability of infrared earth sensor which is attenuated with the running time. The results could be the rules for analyzing the orbit data of IESRI.