一种基于信息融合苹果果实世界定位方法

A world positioning method for apple fruits based on information fusion

构建由Kinect设备、差分GPS设备和陀螺仪组成的信息获取系统,推导RGB图像中苹果果实世界坐标的计算方法。利用Kinect设备获取果园果树RGB图像和深度图像,差分GPS全球定位系统和陀螺仪分别获取Kinect相机位置信息和姿态信息。融合RGB图像和深度图像,利用相对位置定位模型,计算苹果圆心相机空间坐标,融合相机位置信息和姿态信息,利用空间三维坐标转换原理,建立绝对位置定位模型计算苹果世界坐标,对每个果实进行世界空间位置唯一标定。结果表明,果实相对平均定位误差0.035 m,果实绝对定位经度误差0.117 m,纬度误差0.437 m,海拔误差0.145 m。

An information acquisition system was designed and built, which consisted of a Kinect, a differential GPS receiver and an attitude sensor, and a world coordinates calculation approach for apple fruits in a color image was developed depending on this system. The color image and corresponding depth image of fruit tree were taken by the second generation Kinect which was an RGB-D camera, and the world position and the spatial attitude information was obtained by the differential GPS and the digital attitude sensor respectively according to the information acquisition system. Firstly, the camera coordinates of apples' centers were computed by fusing both the RGB and depth information of the color and depth images. Secondly, an absolute positioning model was established according to the three-dimension space coordinate transformation algorithmto calculate the world coordinates of apples, by which the unique world space position of each apple could be acquired. The experiment was carried out, and the results showed that the mean error of the relative positioning was 0.035 m, and for the absolute positioning, the mean distance error of the longitude reached 0.117 m, that of the latitude reached 0.437 m, and that of the altitude reached 0.145 m.