大型可动式抛物柱面天线的关键技术研究

Large parabolic cylinder antenna gradually becomes an important equipment in the exploration of interplanetary space and dark energy because of its unique advantages of high gain, strong directivity and multiple feed. However, since it has a large scale structure, there exist some technical difficulties in system design, electromechanical coupling, and light-weight design. In this project, these issues of system design method, semi-rigid structure, flexible driving, and light-weight design are discussed. The method of Model-Based Systems Engineering (MBSE) is introduced to manage the early design process of antenna and the problem of boring-and-tedious communication and the complexity of design change are improved. The principle of two-center coincidence, the scheme of driving and the scheme of large-span feed support are applied to realize the flexible-driving of semi-rigid structure and the cooperative control of multi-motor, which solves the problems of the feed-phase deviation from the focal line of antenna refector, the large deformation at the connection of feed support, and the synchronous match on the reflector. Tensile structure, stiff cable and cable-truss structure are used in the structure of antenna, and also through the dynamic analysis and optimization of rigid-flexible coupling, light-weight design of antenna is realized. The scaled model is developed, and the performance test is carried out to verify the feasibility of implementation. The study result of this project can be directly taken to design the antenna for IPS and dark-energy detection, and can also gives reference to the adjustment and operation of other large antennas.

大型抛物柱面天线以其高增益、强方向性、多馈源等独特优势，越来越成为行星际、暗能量等天文探测的重要装备。然而，因其结构往往较庞大复杂，在系统设计、机电耦合、轻量化等方面还存在诸多难点。本项目研究大型可动式抛物柱面天线的系统设计方法、半刚性结构与柔性驱动、机电耦合和轻量化设计等关键技术。引入MBSE以可视化系统数据模型形式管理天线设计进程，解决传统设计过程中协调工作繁重、设计更改复杂等问题；提出“两心重合”理论、新型反射面驱动方案和大跨度馈源支撑方案，探究半刚性结构体的柔性驱动方式及多电机协同控制方法，解决馈源相位中心易跑偏、馈源支架变形大遮挡多、反射面单元同步匹配难等问题；引入张拉结构、劲性索和索-桁结构，结合刚柔耦合动力学分析与优化，实现轻量化；研制缩比模型并进行性能测试，最后完善工程应用性。成果可直接应用于IPS和暗能量探测等天线阵研制，并为其它大型天线调试和运行提供技术借鉴。

基于星际探测和深空探测对大型柱面天线的需求，结合“子午工程二期”项目指标，以大型可动IPS射电天线为主要研究对象，探讨了两心重合理论及实现方法、轻量化设计与优化方法、基于MBSE的天线系统设计方法等大型可动式抛物柱面天线的关键技术。.提出馈源旋转中心和反射面旋转中心“两心重合”天线拟轴理论，确定天线索驱动结构设计的总体方案。设计了索牵引滚动轨道，将环形耦合同步控制应用于多索牵引机构中，并运用双闭环反馈控制实现钢索稳定控制。开展多工况静、动力学分析，结果表明其最大形变为0.57mm，最大应力为35.7MPa，均符合设计要求。设计链轮滚子式俯仰配平机构去实现索牵引机构的动态卸荷，开展了链轮滚子式俯仰配平机构实验测试方案。.对天线模型进行数值优化，最优天线体重量降低22.2%、最大面型误差4.77mm、最大变形量13.22mm、最大应力 124.02MPa、一阶固有频率6.85Hz，均满足射电天线技术指标。确定预应力-索为主要结构形式对天线体进行构型设计和受力分析，采用力迭代法求得索网和横索最佳预紧力，最小索应力为0.11MPa，满足工况要求；引入索后天线体重量相比于初始结构降低29.10%。探讨了天线缩比模型实验，验证天线体在实际工况下的力学性能；搭建2m×2.4m缩比模型，结果显示：所选测点变形误差均小于15%，优化后的天线体结构满足实际工况要求。.基于MBSE的方法，建立天线需求域、功能域和架构域的元模型，对SysML进行轻量化扩展，通过需求追溯矩阵和追溯图的结合来实现不同维度的追溯；对天线系统建模过程中的需求变更进行分析研究与模型修改，建立正向和逆向的系统追溯。在天线元模型框架和DSML建模语言的基础上，结合天线领域设计经验和层次分析法，提出基于模型驱动的系统方案优化设计方法，辅助系统设计的优化分析和科学决策，通过多方案的信息优化和比对，验证了基于领域元模型的天线系统建模及设计优化方法的可行性。.本项目研究成果为IPS地面探测设备提供一款新型天线结构，为之后类似大型天线的关键技术设计提供参考。