From images and technical drawings to 3D models: a novel approach to as-built reconstruction

Marker-based photogrammetric as-built reconstruction is a well established method to capture industrial sites. However, to reduce costs and to accelerate the reconstruction procedure, there is an increasing demand for marker-free reconstruction methods. Aiming to eliminate the need for markers, we present a novel approach to as-built reconstruction, which integrates technical drawings as orthographic images seamlessly into the photogrammetric reconstruction process. We introduce a new type of image, the so called co-registered orthographic and perspective (COP) image, which consists of an orthographic view integrated into a perspective view. Metric measurements and reconstruction are possible using only a single COP image. We discuss epipolar geometry for this type of image and we provide orientation and reconstruction methods custom tailored to COP images for points, lines, and cylindric objects. Multiple examples of application in industrial environment show the practical applicability of the presented methods and confirm that the requirements for accuracy in typical applications can well be met.