Schedule-based service choreographies for real-time control loops

• Published in: 2015 IEEE 20th Conference on Emerging Technologies & Factory Automation (ETFA) pp. 1 - 8
• Main Authors: Kothmayr, Thomas, Kemper, Alfons, Scholz, Andreas, Heuer, Jorg
• Format: Conference Proceeding
• Language: English
• Published: IEEE 01.09.2015
• Subjects: Job shop scheduling; Real-time systems; Schedules; Sensors; Service-oriented architecture; Time division multiple access; Timing
• ISSN: 1946-0740; 1946-0759
• DOI: 10.1109/ETFA.2015.7301434

Today's manufacturing industries are undertaking efforts to further increase the flexibility of their facilities. One way to achieve this goal is the development of distributed, service-oriented architectures (SOA). A challenge for SOAs is the continued support of the real-time requirements imposed by industrial control tasks. This paper presents an approach for executing service choreographies with strong real-time guarantees without a central point of control. Engineers can design the automation workflow as a graph of communicating tasks which are then assigned to devices in the network. Our method generates a cyclic, non-preemptive schedule for each device to achieve global cooperation between them. Using an approach that combines several heuristics, a valid solution for over 99% of the 1.2 million test cases was found. On average, this method was over two orders of magnitude faster than an approach based on MIP-solvers.