Opt Express. 2023 May 8;31(10):16952-16973. doi: 10.1364/OE.486816.
In order to expand the field of view and measuremenst range, the camera is often mounted on a two-axis turntable to perform various visual tasks. And the calibration of the position and attitude relationship between the mounted camera and the two-axis turntable is a prerequisite for visual measurement. The turntable is considered an ideal orthogonal two-axis turntable in conventional methods. However, the rotation axes of the actual two-axis turntable may be neither vertical nor intersecting, and the optical center of the mounted camera is not always located in the rotation center of the turntable even for orthogonal two-axis turntables. The quite difference between the actual physical model of the two-axis turntable and the ideal model can cause large errors. Therefore, what we believe to be a novel position and attitude calibration method between a non-orthogonal two-axis turntable and the mounted camera is proposed. This method describes the spatial hetero-planar lines relationship between the azimuth axis and pitch axis of the turntable accurately. By the geometric invariant characteristics of the mounted camera in motion, the axes of turntable are recovered and the base coordinate system is established, and the position and attitude of the camera are calibrated. Simulation and experiments verify the correctness and effectiveness of our proposed method.
为了扩大视野和测量范围，通常将相机安装在两轴转台上以执行各种视觉任务。并且，安装相机与两轴转台之间的位置和姿态关系的校准是视觉测量的前提。在传统方法中，转台被认为是理想的正交两轴转台。然而，实际的两轴转台的旋转轴可能既不垂直也不相交，并且即使对于正交两轴转台，安装的相机的光心也不总是位于转台的旋转中心。两轴转台的实际物理模型与理想模型之间的相当大的差异会导致较大的误差。因此，我们提出了一种新颖的非正交两轴转台和安装相机之间的位置和姿态校准方法。该方法准确描述了转台的方位轴和俯仰轴之间的空间异平面图线关系。通过运动中安装相机的几何不变特征，恢复转台的轴并建立基座坐标系，并校准相机的位置和姿态。仿真和实验验证了我们提出的方法的正确性和有效性。
