A distributed model of concurrency for robot sensorimotor synchronization

An algebra of Petri nets for the dynamic specification of the distributed semantics of task synchronization in hierarchical multiagent robotic systems is developed. The proposed algebra allows for the hierarchical specification of the flow of control and the temporal order of task execution by multiagent systems. Each level of the resulting hierarchies horizontally contains the synchronization structure of task execution and vertically is a generalization of the level below and a specialization of the level above. The horizontal synchronization structures developed by the proposed Petri net model maintain the desirable properties of safeness and liveness by construction. The model utilizes a modularization of complex kinematic chains, a classification of primitive tasks, and a concept of functional time dependency