Closed-loop solution method of active vision reconstruction via a 3D reference and an external camera

Laser-plane-based vision reconstruction is an important approach for 3D profile measurement and optical inspection. This study develops a 3D reconstruction method to measure the object with a flexible method. The active vision reconstruction includes an external camera and a 3D reference with an internal camera and laser projector. The 3D calibration object, the external camera, and the 3D reference constitute a closed loop. The internal camera, the 3D calibration object, and the 3D reference compose the other closed loop. The intrinsic invariants of the 3D reference with an internal camera and laser projector are determined by the two loops above. The benefit of the method is to cancel the position constraint for the active vision system with the cubic LED reference and the monocular external camera. Furthermore, as the external camera captures only the images of the 3D reference, the reconstruction system of the projector and the camera is flexible to observe the occlusion location on the measured object. The methods, including the calibration model and reconstruction model of the measurement system, are verified by experiments to demonstrate the potential applications.