Distance and angle measurement using monocular vision

Accurate localization is a fundamental challenge and one of the essential tasks in mobile robot applications. In this paper, we proposed an image-based method to measure parameters of an object by a visual camera/monocular vision. If the sizes of the object are unknown, based on information extracted from two images at two different positions of the camera on the optical axis, these sizes can be calculated accurately. Furthermore, the distance and direction (angle) of the object can also be determined. If the dimensions of the object are known, just one image is enough to determine distance and direction (angle) of the object. Unlike other existing methods, the proposed method does not require the object to be perpendicular to the optical axis of the camera.