Reconstruction of transparent objects in unstructured scenes with a depth camera

The visual 3D reconstruction of transparent objects in unstructured scenes is challenging due to the complex image formation principles underlying their visual appearance. Most state-of-the-art reconstruction methods ignore this problem and assume Lambertian reflection. Yet, transparent objects are relevant scene information for applications in intelligent robotics (such as grasping) or virtual reality. In this work, we present an approach to detect non-planar transparent objects, like bottles or glasses, by specifically searching for geometry inconsistencies caused by refraction or reflection. Depth information is acquired using a Kinect sensor, which is moved within the scene in order to acquire multiple views. The individual measurements are combined into a 3D volume, yielding the objects' location and a rough shape estimate. Results are presented using various household objects made of glass or plastic.