An improved two-point calibration method for stereo vision with rotating cameras in large FOV

Abstract

ABSTRACTAt present, binocular stereo vision is gradually being applied for 3D coordinate measurements in large fields of view (FOVs). In this study, a binocular stereo vision system with fixed and non-zooming cameras in a large FOV is constructed, in which cameras can rotate horizontally and vertically. All intrinsic parameters except the focal length of the cameras are set to default values and these focal lengths are calibrated offline in advance. Only the pitch angle and yaw angle of each camera need to be obtained during rotation. Therefore, we present a novel calibration method by using two control points and transform the imaging model of the pitch and yaw angles into a quadratic equation of the tangent value of the pitch angle so that the closed-form solutions of the pitch and yaw angles can be obtained. Computer simulation and real experiments demonstrate the effectiveness of the proposed method.