Title :
Improving time performances of distributed PLC applications
Author :
Kouthon, T. ; Decotignie, J.-D.
Author_Institution :
Dept. of Comput. Sci., Swiss Federal Inst. of Technol., Lausanne, Switzerland
Abstract :
PLC applications are extensively used in industry to control and repetitive processes such as manufacturing cell management, fly-by-wire control, or nuclear plant shutdown systems. Because of recent developments in local area real-time networks, distributing PLC applications over such networks has now become feasible. A distributed system consists of network nodes (or stations) connected to each other by a hardware communication medium. However, one known shortcoming of distribution is the data transmission overhead, between processes assigned to different nodes that need to communicate. Such overhead signifies a degradation in time performances. The issue addressed in this paper, is to determine how to improve the time performances of distributed PLC applications. We address the problem from a scheduling point of view, and since it is proven to be NP-complete, we also present heuristics to solve it
Keywords :
computational complexity; distributed control; heuristic programming; industrial control; local area networks; programmable controllers; real-time systems; LAN; NP-complete problem; data transmission overhead; distributed PLC applications; distributed system; fly-by-wire control; hardware communication medium; heuristics; local area real-time networks; manufacturing cell management; nuclear plant shutdown systems; time performances; Communication system control; Control systems; Data communication; Electrical equipment industry; Hardware; Industrial control; Manufacturing industries; Manufacturing processes; Process control; Programmable control;
Conference_Titel :
Emerging Technologies and Factory Automation, 1996. EFTA '96. Proceedings., 1996 IEEE Conference on
Conference_Location :
Kauai, HI
Print_ISBN :
0-7803-3685-2
DOI :
10.1109/ETFA.1996.573980
