State feedback stabilizing controller for the failure recovery of timed discrete event systems

Redundancy Based Controller Reconfiguration for Fault Recovery of Manufacturing Systems

“…ω k , if the following conditions hold: 1. σ x is a subsequence of ω k (ω k = υσ x η; υ and η are a prefix and a sufix of ω k , respectively), 2. there exists a σ y redundant to σ x , 3. every faulty transition in ω k belongs to a σ x , SuRP-A04. 4 4. none faulty transition belongs to σ y , 5. there exists a new controllable sequence ω 0 k = υσ y η. Proof: Assume that a fault in ω k occurs; by 2) and 4) these faults are located in the subsequence σ x of ω k , and by 1) and 3) there exists σ y redundant to σ x , such that σ y does not have faults.…”

“…based on redundancy of holons with checkpoints [2]; or redundancy in skills, capacities and knowledge in agents [3]. Others are based on the computation of alternative action sequences using stabilization concepts [4]; or with predefined alternative sequences [5] [6]. Other approaches use reconfiguration based on input conditioning, alternate path, feedback error recovery, and forward error recovery augmentation methods [7]; reconfiguration with functionality redundancy in agents [8]; or reconfiguration of the controller due to sensor faults [9].…”

Identification of incompatible states in mode switching

“…The main assumption is that the system is effectively operated in only one mode at any one time. Based on previous switching management studies [7,4] we propose both process and controlled process model extensions to formalize compatible states. Compatible states are those for which common component states are functionally coherent in considered modes (incoming and outgoing operating modes).…”

A redundancy based method for Petri net model reconfiguration

“…holon redundancy with checkpoints [1], abilities, capabilities, and knowledge of agents redundancy [2]. Other works are based on the computation of action sequences, e.g., by finding control sequences [3] [4] [5] [6], or by predefined recovery sequences [7] [8] [9]. In addition, the reconfiguration approach is used in [10] [6] [11] [5] for addressing automated fault recovery.…”