高精度星图模拟及有效性验证新方法

为在地面上进行星图模拟以测试星图识别算法和星敏感器性能,提出了一种新的高精度星图模拟方法。该方法利用截面圆和固定区域的性质,根据赤纬值求解赤经跨度来确定选星条件;将选出的导航星通过构建理想星敏感器模型,来求解它们在CCD面阵上的精确位置;根据位置信息,采用TFT液晶光阀,以实现高质量的星图模拟;利用星间角距和投影原理的性质来验证星图模拟的有效性。仿真实验结果表明,与现有星图模拟方法相比,此方法选星速度快,模拟实时性好,准确率达到98.8742%,位置精度达到1/50个像素。

High-precision simulation of star map and its validity check

In order to test the algorithms of star map identification and the performance of star sensor by simulating star map on the ground, a new and high precision method for simulating star map is presented. This method makes use of the property of sectional circle and fixed field to derive the span of longitude based on latitude value as the condition for selecting stars; By constructing an ideal model of star sensor, the accurate positions of the selected guide stars on the CCD plane are derived. On the basis of position information and TFT liquid crystal light valve, high quality simulation of star map is performed. The validity of simulating star map is verified by using the angle-distance of stars and projection theorem. The simulation results show that compared with current common star map simulation methods, the proposed method features fast speed of choosing guide stars and simulating star map in real-time with good precision up to 98.8742% and position accuracy to 1/50 of pixel.