基于GPS基准点的航空吊舱垂直下视目标定位方法研究

传统的无人机目标定位技术要求在外场对惯导基准,减振器基座和光电平台坐标系之间进行复杂的标校,利用空间坐标系转换理论对地面目标进行定位。但由于各坐标系之间标校的偏差和飞机经纬度的误差,使得定位结果精度较低。航空吊舱采用惯导系统和光电转台固联的安装方式,可以彻底消除减振器带来的误差。光电转台在垂直下视状态下,利用飞机海拔高度和激光测距值就可以算出目标点海拔高度。同时利用目标点和GPS基准点之间的像素关系并结合基准点地理经纬度可以准确计算出目标点的GPS坐标。通过仿真实验可以看出航空吊舱在垂直下视模式下,基于GPS基准点进行地面目标定位的方法可以得到较高的精度。相比空间坐标变换的定位方法节省了复杂的系统标校过程,简化了算法公式,不仅提高了定位精度,还增加了解算的实时性。

Air Pod Target Location Method Research Using GPS Datum Mark in Vertical Down of View

Traditional UAS targeting technology uses space coordinate transformation theory to locate targets.It requires complicated calibration between INS benchmark,shock absorber base and optical turret coordinate.The accuracy of locating results is low due to the deviation of coordinate calibration and the latitude and longitude error of UAS.Errors brought by shock absorber can be eliminated thoroughly when INS and optical turret solid alliance installed in air pod.Using height value of airplane and laser distance measurement value,optical turret can work out the height of target in vertical down of view.It can also calculate GPS coordinate of target accurately using pixels relationship between target and GPS datum mark combined with the latitude and longitude of datum mark.Simulation test shows an accuracy result of ground target locating method based on GPS datum mark when air pod in vertical down of view status.Comparing with space coordinate transformation locating method,it saves complicated system calibration process,simplifies arithmetic formula,improves the locating accuracy and enhances the real-time feature of solution.