Separated approach for “active” monitoring of discrete event systems

Abstract In this paper, we propose an approach to realize “active” monitoring for Discrete Event Systems. The “active” monitoring means that human operators have a good perception of process state and detect failures by their own observation of process running. This approach uses one model of the operative part to design two complementary monitoring tools. The first tool is used to follow the normal operating function. Indeed only sensors are not sufficient to guarantee an accurate perception of the process state. The idea is to supply high-level information to human operator or automated system in order to improve the situation awareness. However, it is important to supply reliable information. For that, the second complementary tool detects failures of sensors and consequently generates an alarm. This approach is a separated one since it models the behavior of the operative part independently of the command part. Additionally this approach is simple to be implemented and it better controls the combinatory explosion. An experimental prototype based on this approach is developed. Finally two examples of implementation are studied to illustrate the functionality of this approach.