A HIERARCHICAL 3D CIRCLE DETECTION ALGORITHM APPLIED IN A GRASPING SCENARIO
Emre Başeski, Dirk Kraft, Norbert Krüger · 2009
In this work, we address the problem of 3D circle detection in a hierarchical representation which contains 2D and 3D information in the form of multi-modal primitives and their perceptual organizations in terms of contours. Semantic reasoning on higher levels leads to hypotheses that then become verified on lower levels by feedback mechanisms. The effects of uncertainties in visually extracted 3D information can be minimized by detecting a shape in 2D and calculating its dimensions and location in 3D. Therefore, we use the fact that the perspective projection of a circle on the image plane is an ellipse and we create 3D circle hypotheses from 2D ellipses and the planes that they lie on. Afterwards, these hypotheses are verified in 2D, where the orientation and location information is more reliable than in 3D. For evaluation purposes, the algorithm is applied in a robotics application for grasping cylindrical objects.