DEM和单相机的弹落点坐标测量方法

Coordinate measurement method of bomb falling point based on DEM and single camera

针对大视场远距离复杂地形条件下的弹落点坐标测量,提出一种结合数字高程模型(Digital Elevation Model,DEM)的单目视觉测量方法。该方法不依赖目标或场景信息,只需单幅弹落点图像,即可快速解算出弹落点的三维坐标。首先,利用图像二维信息求解出相机与弹落点相连的空间直线;然后,根据相机与靶心的相对位置确定直线上的搜索起点和搜索步距,将直线上的搜索点与数字高程地图进行匹配;最终求解出弹落点的三维坐标。现场试验结果表明:相机距监测区域大于500 m,监测区域视场宽度为300 m时,相对定位误差优于0.3%。该方法结构简单、成本低、运算速度快,适用于复杂地形条件下的弹落点坐标测量。

According to the bomb falling point coordinate measurement of wide field under complex terrain conditions,a monocular vision measurement method combined with digital elevation model(DEM)was proposed.The object or scene information was not relied on in the method.The 3D coordinate of the bomb falling point can quickly be calculated with only one bomb fall image of single camera in the method.Firstly,the two-dimensional information of the image was used to solve the space linear that camera and the bomb falling point were connected;Then,according to the relative position of the camera and the target to determine the search starting point and step on the line,the line search and digital map of elevation were matched;Finally,the 3D coordinates of bombs were solved.Field test results show that when the distance between the camera and monitoring area is more than 500 m,and the width of the field of view is 300 m,the relative positioning error is better than 0.3%.The advantages of simple structure,low cost,fast operation speed,and is applicable to coordinate measurement of bomb falling point under complicated terrain conditions were proved in the method.