Formalizing Human–Machine Interactions for Adaptive Automation in Smart Manufacturing

Human-machine interaction is one of the most crucial aspects of advanced manufacturing systems that have advanced to so-called smart manufacturing systems. In this regard, this paper presents a framework for formalizing human-machine manufacturing systems. The human-machine system considered in this paper consists of the following three main components: a human supervisor; several cells, each of which is composed of a human operator and a machine; and interfaces. A human operator interacts with a machine in a cell and performs manufacturing tasks based on commands given by the supervisor. Meanwhile, the supervisor is responsible for performing exception handling tasks in response to unanticipated events reported by the cells. With the proposed model, desirable specifications are constructed, which include a condition free of mode confusion, manufacturing task goal reachability, and exception handling task supportability in human- machine manufacturing systems. It is also suggested that adaptive automation with varying levels of information abstraction to humans can be accommodated by the proposed framework. As an illustrative example, we demonstrate the formal models and specifications and the applicability of adaptive automation with a case study of a simple chair assembly system.