Robust deadlock avoidance control for AMSs with assembly operations embedded in flexible routes using Petri nets

• Published in: IET control theory & applications Vol. 13; no. 11; pp. 1579 - 1590
• Main Authors: Du, Nan, Hu, He Suan
• Format: Journal Article
• Language: English
• Published: The Institution of Engineering and Technology 23.07.2019
• Subjects: AMSs; assembly operations; automated manufacturing systems; blocking problems; consideration deadlock; currently‐available resources; deadlock‐free supervisory control; discrete event systems; failed resource; flexible manufacturing systems; flexible routes; manufacturing systems; numerous researchers; Petri nets; popular research subject; Research Article; resource allocation; resource failures; robust control; robust deadlock avoidance control; robust supervisor; shared resource capacity; stagnant parts; Petri nets; flexible manufacturing systems; flexible routes; popular research subject; shared resource capacity; robust supervisor; automated manufacturing systems; discrete event systems; AMSs; resource allocation; robust deadlock avoidance control; consideration deadlock; currently-available resources; resource failures; stagnant parts; failed resource; robust control; manufacturing systems; numerous researchers; assembly operations; blocking problems; deadlock-free supervisory control
• ISSN: 1751-8644; 1751-8652
• DOI: 10.1049/iet-cta.2018.5398

Deadlock-free supervisory control for automated manufacturing systems (AMSs) has been a popular research subject. However, for numerous researchers, their studies are merely practicable on the assumption that resources cannot fail. In practice, resource failures can occur unexpectedly. In this study, the authors take into consideration deadlock and blocking problems in systems with assembly operations embedded in flexible routes. Their objective is to develop a robust supervisor that controls resource allocation and selects flexible routes such that stagnant parts requiring failed resources do not block the movement of parts not necessarily requiring failed resources. That is to say, it must ensure that parts not necessarily requiring any failed resource can continue their operations. The proposed policy tries to take full advantage of the shared resource capacity to improve systems' performance. By modelling AMSs with Petri nets, their robust supervisor predicts in advance whether the currently-available resources are sufficient to support a token to advance into the desired destination in a single process. The method is achieved in an online and distributed way and avoids enumerating states. At last, several simulation examples show the correctness of their proposed method.