A robot system for unstructured environments based on an environment model and manipulation skills

A model-based robot system is described. This system was developed to replace and improve upon the conventional robot control scheme of teaching-by-showing and replay. The key concept of this system consists of the combination of manipulation skills with an environment model. The model provides the geometric structure and the physical properties of the objects in the environment. Manipulation skills enable reliable task execution, in the presence of unavoidable errors, and uncertainties. Skills are implemented within the hybrid position/velocity/force control scheme and incorporate sensing procedures to detect the state to be achieved. An experiment involving the disassembly of a valve using this system is presented