大柔性太阳帆航天器姿态机动的振动抑制研究

Attitude maneuver of the large flexible solar sail spacecraft easily arouses its own flexible vibration, because the large flexible solar sail has not mass-dominant central rigid body as general flexible spacecraft, flexible vibration will not only produce a coupling torque, but also make drastic change in the moment of inertia and appearance of additional disturbance torque. Then the dynamic features of solar sail are changed. These effects will seriously affect the process of attitude maneuver. The geneal studies of vibration suppression just only ensure the flexible vibration be zero after the end of attitude maneuver, but the flexible vibration during maneuver still exists. Because of the complex dynamics characteristics of solar sail spacecraft, the flexible vibration suppression of solar sail attitude maneuver are required not only to ensure the flexible vibration be zero after the end of attitude maneuver, but also try to reduce or eliminate the flexible vibration during maneuver. Therefor, the dynamics modeling and simplification methods are studied to reflect the fully flexible vibration coupling influence. From two aspects of improvement of traditional vibration suppression method and design new vibration suppression method, the vibration suppression methods of solar sail are discussed to reduce or eliminate the flexible vibration of maneuver. So, the solar sail attitude maneuver can successful complete. Related research results have important scientific significance and application value to dynamics modeling and control design of all kinds of large flexible spacecraft.

大柔性太阳帆航天器的姿态机动易激起自身的柔性振动，不同于一般的柔性航天器，由于太阳帆航天器没有质量占优的中心刚体，柔性振动不但会产生耦合力矩，还会使转动惯量发生剧烈变化，改变太阳帆的动力学特性，同时因受力不均产生额外的干扰力矩，这些影响将严重影响姿态机动过程。通常的振动抑制研究只考虑使姿态机动结束后的柔性振动为零，忽略了机动过程中的柔性振动。由于太阳帆航天器复杂的动力学特性，针对太阳帆姿态机动的柔性振动抑制，不但要保证机动结束后的柔性振动为零，还要尽量减小或消除机动过程中的柔性振动。为此，本课题首先研究充分反映柔性振动影响的耦合动力学建模方法及模型简化方法，然后从改进传统振动抑制方法和设计新型振动抑制方法两个方面，探讨太阳帆柔性振动抑制方法，减小或消除机动过程中的柔性振动，保证大柔性太阳帆姿态机动的顺利完成。相关研究成果对大柔性航天器动力学建模和控制设计具有重要的科学意义和应用价值。

太阳帆是进行深空探测和行星际航行最有前景的推进方式，但大面质比的太阳帆结构易发生柔性变形和振动，进而影响太阳帆航天器的姿态稳定和运行轨迹。本项目针对这个问题，开展柔性太阳帆航天器姿态机动的振动抑制研究。.本项目以带有控制叶片的方形太阳帆为对象，主要从动力学建模和主动振动抑制方法两个角度开展研究。应用拉格朗日建模原理，完成太阳帆航天器刚柔耦合的多体动力学建模。然后考虑控制小帆的有效运动范围，完成控制小帆输出力矩解耦和分配简化。针对太阳帆快速姿态机动的控制过程，设计输入成型和复合控制振动抑制方法。.本项目取得两个重要研究成果。一个是得到了简化的太阳航天器刚柔耦合多体动力学方程，包括控制小帆输出力矩的解耦简化和等效振动模型。第二个是提出了复合振动抑制方法，不但能消除机动过程中的太阳帆变形，而且没有延迟。这两个研究成果为实现太阳帆航天器在轨实际运行，积累了宝贵的经验。