火星次表层探测雷达展开机构设计与试验

Design and experiment of deployment mechanism for Mars subsurface radar

利用卷筒式伸杆机构展开后为金属薄带螺旋层叠式构型可作为天线的特性,提出了“类偶极子”的布局方案,使用两套卷筒式伸杆机构向反方向展开形成探测基线,解决了火星探测任务中次表层探测雷达天线展开长度需求大和收拢包络有限的矛盾。与其他次表层雷达天线展开机构进行了对比,指出“天问一号”的展开机构具有最小的收纳体积,最大的展收比,最适合需要安装多套载荷的应用场合。对卷筒式伸杆机构的组成及工作原理进行了阐述,给出了次表层探测雷达展开机构机械性能与其核心部件弹性卷筒构型参数间的关系,获得了弹性卷筒驱动力和基频的计算公式。分析结果表明:卷筒式伸杆机构展开状态基频由弹性卷筒的带宽、壁厚以及展开后的根部半径和末端半径决定;驱动力与带材的弹性模量、带宽成正比,与带厚的三次方成正比,其中带厚对驱动力的影响最大。对卷筒式伸杆机构的基频和驱动力进行了测试,试验结果与分析结果吻合良好。

Taking advantage of the characteristics that the deployment STACER can be used as an antenna,two sets of STACER were used to form a detection baseline,which solved the contradiction between the length requirement and the limited folding envelope in the TianWen-1 mission.Compared with other subsurface radar antenna deployment mechanisms,it was pointed out that the STACER had the smallest storage volume and the largest stow ratio,and was most suitable for applications where multiple sets of loads need to be installed.The composition and working principle of the STACER were described.The relationship between the mechanical performance and the configuration parameters was given.The calculation formulas of the driving force and the fundamental frequency of the STACER were obtained.The formulas show that the fundamental frequency is determined by the strip width,thickness,the root radius and tip radius.The driving force is in proportion to the elastic modulus,strip width,and the cubic of the strip thickness.The strip thickness has the greatest influence on the driving force.The fundamental frequency and driving force of the STACER are tested,and the test results are consistent with the analysis results.