Discrete Event Net Based Modeling and Control System Design for Real-Time Concurrent Control of Multiple Robot Systems

Gen’ichi Yasuda

Department of Human and Computer Intelligence, Nagasaki Institute of Applied Science, Nagasaki, Japan.

DOI: 10.4236/ica.2012.32015                

Abstract

This paper deals with control system design and implementation problems encountered in multiple robot systems. The methodology developed is depicted by a set of coordination mechanisms using hierarchical net structures and their accompanying rules. With the net models, the hierarchical and distributed control system is designed for an assembly task. Synchronization commands allow coordination of the movements of the robots. The net models make concurrency of the movements of the robots transparent to users. The net based machine controller executes robot motion control through the communication with the external robot controller using the command/response concept. Sensory signals indicating the change of state of robots are used to trigger or initiate tasks. Simultaneous movement of the robots is obtained by creating different background threads running in parallel under Windows OS. The multilevel hierarchical control system can be consistently constructed using net models.

Keywords

Multiple Robot Systems; Concurrent Control; Control System Design; Net Models; Discrete Event Systems

Conflicts of Interest

The authors declare no conflicts of interest.

References

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