直线特征的交互矩阵求取

Determination for Interactive Matrix of Line Feature

直线特征在视觉跟踪、视觉伺服中具有重要作用,但目前的直线交互矩阵的求取受到制约,需要已知含有直线的平面在摄像机坐标系中的方程参数.为摆脱含有直线的平面参数的约束,本文利用两点的极坐标推导出直线的交互矩阵,并给出直线交互矩阵求取方法.经分析得知,对于与摄像机光轴接近垂直的直线,其在成像平面上的角度变化主要受摄像机姿态变化的影响,对摄像机的位置变化不敏感.对于与摄像机光轴平行的直线,其在成像平面上的角度变化受摄像机旋转以及垂直于光轴平移的影响较大.实验结果验证了本文方法的有效性.

Line features are very important for visual tracking and visual servoing. However, determination of the interactive matrix of line feature is possible only if the parameters of the plane containing the line are known in the camera＇s coordinates. In this paper, the interactive matrix of line feature is derived with two points＇ polar coordinates in order to avoid the parameters requirement for the plane containing the line. Then determination for interactive matrix of line feature is presented. Analysis of the interactive matrix shows that the angle^s variation of line feature is mainly influenced by the orientation^s variation of the camera and insensitive to translations of camera if the line is almost perpendicular to the camerats optical axis. The angle^s variation of line feature for the line parallel to the optical axis is apparently influenced by the camera＇s translations vertical to the optical axis and rotations. Experimental results verify the effectiveness of the proposed method.