Model-based stereo-tracking of non-polyhedral objects for automatic disassembly experiments

Automatic disassembly tasks in the engine compartment of a used car constitute a challenge for control of a disassembly robot by machine vision. We adopt a direct association of individual edge elements with model segments obtained from scene domain models of tools and workpieces. In addition, we switch from a conventional single camera hand-eye configuration to a movable stereo-configuration mounted on a separate "observer" robot. A generalisation of our model-based tracking includes the parameters, which characterize the relative pose of one camera with respect to the other one of the stereo-camera set-up, into the set of parameters to be re-estimated for each new stereo image pair. This results in a continuous re-calibration during a relative movement between stereo-camera set-up and tracked objects. Our approach had to be extended further in order to cope with non-polyhedral objects. The methodological improvements of machine vision in the course of this research are described in detail.