大型空间可展开索网-框架组合结构的高形面精度设计理论与方法

Large deployable cable net-frame combination structures are a broad class of key structures for completing space missions of spacecrafts. The most representative structures are space deployable mesh reflector antennas. The cable net structure is shaped under the interaction of internal tensions and supporting frames to satisfy the accuracy requirements. Now the increasing demands for large-scale deployable cable net-frame combination structures are contradictory with improving their surface accuracy. To address this problem, first, the topological connections between kinematically indeterminate supporting frames and statically indeterminate cable net structures are investigated, which can improve the topological synthesis theory of statically determinate configurations of large deployable cable net-frame combination structures. Second, under considering the impacts of high and low temperature alternation in space environments, the design methods of surface geodesic layout and the reasonable tensions in cable net structures are developed to perfect the working profile design theory of cable net-frame combination structures. Finally, for the deteriorated surface accuracy resulting from structural deformations and vibrations caused by space microgravity and heat alternating environments, the active surface adjustment and active-passive vibration control technologies are studied to establish the active surface control theory of cable net-frame combination structures. The design, simulations and experimental verifications for high surface accuracy cable net-frame combination structures are carried out, and provide theoretical foundations and technical methods for the engineering designs of large and high accuracy deployable space cable net-frame combination structures.

大型可展开索网-框架组合结构是实现航天器任务的一大类关键结构，最具代表性的是空间可展开网状反射面天线，其柔性索网结构在内部张力和支撑框架的共同作用下形成满足精度要求的形状。目前，可展开索网-框架组合结构的大型化发展需求与形面精度提高之间是矛盾的。为此，本项目首先揭示运动不确定的支撑框架和静力不确定的索网结构之间的拓扑连接关系，完善大型索网-框架组合结构的静力确定性拓扑构型综合理论；其次，考虑空间高低温交变环境的影响，研究网面测地线几何布局和索中合理张力的设计方法，完善索网-框架组合结构的工作轮廓设计理论；最后，针对空间微重力和热交变环境下产生变形和振动而导致形面精度变差问题，研究形面主动调整和主被动振动控制技术，完善索网-框架组合结构的形面主动控制理论。进行高形面精度索网-框架组合结构的设计、仿真和实验验证，为大型、高精度空间可展开索网-框架组合结构的工程设计提供理论基础和技术方法。

以大型可展开索网-框架组合结构为研究对象，尤其是网状反射面天线结构，从集成设计角度，采用理论建模、数值仿真和实验方法，研究了静力确定性拓扑构型综合、网面测地线几何布局设计、索网预张力的均匀性设计、形面主动调整和主被动振动控制等关键技术，建立了大型空间可展开索网-框架组合结构的高形面精度设计理论与方法，解决了大型化发展需求与形面精度难以提高之间的矛盾问题，攻克了大型高精度空间可展开结构研制的技术瓶颈，使形面精度RMS达到亚毫米级，结构重要频率处的振动响应幅值下降50%，满足了电性能对大型高精度索网-框架组合结构的关键要求。研究成果已应用于我国通信技术试验卫星一号（2015年9月19日成功发射）可展开网状天线（已成功在轨工作）、我国天通一号01星（2016年8月6日成功发射）大型星载天线（已成功在轨工作）和某高精度伞状天线工程样机的设计与研制，为高精度网状可展开天线的设计与优化做出了重要贡献。