Stigmergy in Holonic Manufacturing Systems

Multi-agent coordination and control, as encountered in holonic manufacturing system implementations, can be classified according to two categories of agent interaction schemes. In the first category, agents explicitly interact and negotiate with each other. A well-known example is the contract net protocol. In the second category, the agents interact and coordinate indirectly by changing their "environment". These changes are observed by other agents and influence their behaviour. A form of coordination based on such an indirect interaction is called stigmergy. This paper describes a specific type of coordination and control belonging to the second category. It also discusses how this enables the design of a system in which agents make global information locally available to other agents without any agent becoming exposed to global system properties.