Model-Based Hierarchical Diagnosis Of Robotic Assembly Cell

Abstract

Robotic assembly cell is a hierarchically designed artifact for certain automatic assembly. Diagnosis of a robotic assembly cell requires failure recognition, cell representation, and reasoning. This paper describes robot cell representation and model-based causal reasoning for diagnosis. The robotic assembly cell is characterized by the assembly operations and the physical environments. The assembly operations are modeled as asynchronous parallel processes and the physical environments are modeled as functional device units. A layered causal network is constructed to represent the causal relations of the robotic assembly cell and the model-based causal reasoning is performed for cell diagnosis with the aids of hierarchical reasoners. This approach can be applied easily to an existing robot cell and is not limited to any cell design architecture.