Study On Attitude Control Of Solar Sail Spaceraft

Many researchers and areocraft organizations focus on solar sail spacecraft. Solar sail spacecraft was an important field of research because of the dependence of a solar sail trajectory on the attitude of the sail over time. This paper paid attention to conceptual designing, dynamic modeling and characters of attitude control methods. The thesis included several parts as follows.Firstly, solar pressure model was presented. Some parameters were given to characterize performance of solar sail spacecraft. This thesis designed several spacecraft concepts for different attitude control methods, for example, sailcraft with control boom, sailcraft with control vanes, sailcraft with fixed vanes, etc. In addition, attitude control principles were analyzed, and inertia tensor expressions were calculated.Secondly, considering control moment of control boom and reaction wheel, sun radiation pressure force of solar sail, sun gravitation, rotational dynamics of sailcraft with control boom were developed; considering sun radiation pressure force of control vanes and sun gravitation, rotational dynamics of sailcraft with control vanes were developed. After analyzing controllability and stability, attitude controller is found by linearizing the attitude control dynamics about an equilibrium point. This thesis ran a series of simulations to characterize the behavior of attitude control methods using control boom and control vanes.Finally, Rotational dynamics of a spinning sailcraft were developed which was in the presence of center-of-mass/center-of-pressure offset, the results of simulations showed that an effective solution to the problem of maintaining a desired orientation of a sailcraft was to spin the spacecraft in the fashion of spinning set about special axis. Considering sun radiation pressure force of fixed vanes and disturb torque of solar sail, attitude dynamics of sailcraft with four fixed vanes were developed which was in the presence of center-of-mass/center-of-pressure offset. The results of simulation showed that sailcraft could be stable.