Fault Detection and Recovery by Hybrid Petri Nets for Automated Drug Preparation Systems

:This paper presents an event-based monitor that ensures timely and accurate detection and recovery of system task faults. The monitor model is based on first order hybrid Petri nets, i.e., Petri nets that make use of first order fluid approximation. The proposed fault detection technique relies on a modular framework, so that elementary monitors can be connected with other monitors to check more complex systems while avoiding the state space explosion problem. Moreover, a fault detection and recovery monitor is specified for a system devoted to the automated preparation of pharmaceutical drugs.