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A control strategy for single axis pointing of micro-satellites is proposed which uses only magnetictorquers. This method is useful in satellites′ safe modes and other specific situations. It contains the following steps: firstly, a geometry algorithm is utilized to extend the collection of the rotation axis to a plane, along which the current and target directions can coincide; secondly, an angle acceleration plane is found by affine transaction from the perpendicular plane of the local geomagnetic field with the satellite′s inertial matrix; thirdly, a controller that works along the intersecting line of the rotation axis plane and the angle acceleration plane is constructed to control both the rotating direction and the speed. Compared with the existing methods, this new method has advantages such as no additional disturbance from magnetic torque, less limitation from orbit shape as well as inertia products need not to be zero. The performance of the controller is validated in simulation, in which the Sun pointing and the Earth pointing with single axis are realized. [ABSTRACT FROM AUTHOR]

： This paper considers flows passing a cylindrical spacecraft, with a hat ahead it and an open orifice through it, at an altitude of 200 km, using the test particle Monte Carlo (TPMC) method. The computational results of the axial and normal force coefficients from the TPMC method are in excellent agreement with those from the direct simulation Monte Carlo (DSMC), meaning that the TPMC method used here is valid and applicable to problems where external and internal flows exist simultaneously. Besides，the TPMC runs 2000 times faster than the DSMC，and the memory storage it needs is 1 􀀀 2 orders of magnitude less than that of the latter. In a small range of angles of attack，the existence of the open orifice decreases the pressure drags and increases the friction drags, with an overall effect of reducing the total drags. Moreover, the shadowing of orifice from flows by external surfaces and multiple reflections within the inner surface of the orifice reduce an appreciable pressure on the inner surface of the orifice，and the effect of multiple reflections becomes the strongest in the middle part of the orifice in the axial direction. [ABSTRACT FROM AUTHOR]

The structure of flexible wire mesh tire for manned lunar roving vehicle is comparatively special. The integrated design of tire drive and transmission is implemented. It consists of assembled aluminum alloy hub, inner spring bump stop and wire mesh tire. Based on the wheel-soil interaction terramechanics and a part-experience method, the calculation of driving power and torque of single wheel is completed. Then the hub driving motors and harmonic reductions gears are selected by considering main technical factors such as mass and power constraints, etc. Finite element analysis of assembled aluminum alloy hub is done according to different conditions of static analysis and dynamic-bend fatigue experiment method. The structure of flexible wire mesh tire is improved by considering the results of finite element analysis. At the same time, the inner spring bump stop is analyzed and the technical flow-chart of wire mesh tire is researched and verified. This provides a technical basis for developing wheel for manned lunar roving vehicle which adapts deformable rough terrain on the lunar surface with large loaded, low power consumption and big driving force. [ABSTRACT FROM AUTHOR]

In this article, the Class and Shape Transformation (CST) method for general 3D surface is introduced, the mathematical model of the CST method is analyzed, and a multi-block CST method is presented. The multi-block CST method connects adjacent surfaces smoothly and remains the properties of CST method. It reduces the number of design variables for surfaces with different curvature distributions, and can also model the different classes of surfaces uniformly. Aerodynamic shape optimization design is built based on the multi-block CST method, genetic algorithms and hypersonic aerodynamic engineering calculations, and aerodynamic characteristics of a quasi-waverider wing-body vehicle have improved significantly after optimization. The study shows that multi-block CST method with fewer design variables and higher fidelity extends the applications of CST method dramatically. [ABSTRACT FROM AUTHOR]

In this paper, the development of the lunar lander for manned lunar exploration is surveyed, and the function, technical specification and buffering mode are analyzed. And then the design of the Apollo and Altair lunar lander is discussed. Finally, considering the concerned technologues of manned lunar exploration in china, some key technologies concerned with manned lunar lander are brought forward. [ABSTRACT FROM AUTHOR]

The edge heat leakage will generate if the shields in multilayer insulation (MLI) can't form a closed system, thus producing certain effect on the performance of heat insulation. The two dimensional steady state and combined radiation/conduction heat transfer in MLI is modeled by using the finite element method to simulate the thermal loss from edge of MLI. The effects of design parameters such as mounting area, layer density, thermal conductivity and emissivity of pressure-sensitive tape on the edge heat leakage are analyzed. Two cases that whether the boundary of MLI is covered or not are compared to decide which one is better in heat insulation. Based on the analysis results some useful designs that help to reduce thermal loss from edge of MLI are proposed. [ABSTRACT FROM AUTHOR]

The performances of the ADAM-type mast, such as mass, packaging size, stiffness and strength, are determined by its configuration parameters. A new design of configuration parameters based on maximizing specific stiffness was presented. By MATLAB and ANSYS joint simulation, the varying of specific stiffness with different configuration parameters was analyzed. The simulation results show that the optimum value of the length ratio of longeron to batten and the canister radius increases with the increase of the length of mast, when the length of ADAM-type varies in the range of 20 to 100 meters. While the length of mast is 20, 60, and 100 meters, the optimum value of the canister radius varies from 0.3 to 0.4 meter, 0.5 to 0.7 meter and 0.6 to 0.9 meter respectively. The design flow of configuration parameter based on maximizing specific stiffness is as follow: the canister radius is settled at first, then the length ratio of longeron to batten should be determined, and the number of longitudinal member could he finally settled. By this method, configuration parameters of the mast in the SRTM program are designed, and the results approximate to that of ADAM's. [ABSTRACT FROM AUTHOR]

It is an important step for spacecraft design and analysis to convert random vibration load to quasi static design load, which influences mass of spacecraft structure directly. The theory and methods of design load based on the peak value of acceleration response and displacement response were simply introduced. The differences between the two methods were compared by analytics and FEM. The design load based on the peak value of acceleration response is larger than that based on the peak value of displacement response. The design load based on the peak value of displacement response is recommended and will lighten mass of spacecraft structure. [ABSTRACT FROM AUTHOR]