Mapping of smart field device profiles to web services

A high degree of interoperability in decentralised or distributed automation systems is achieved by smart field device profiles. Profiles are very common for nearly all field bus systems for a long period of time. The basic models of these profiles are usually (1) parameter lists with the related behaviour descriptions for example state machines, (2) function block profiles or (3) object based profiles. Common for all of them is that there is a tight coupled connection between the field devices and host devices such as PLCs. Usually there is no direct connection between the field devices. Future automation systems tend to migrate to more distribution among the system components and to more loose coupled paradigm. This paradigm is used in service oriented architectures (SOA) which are mainly applied in business and IT applications. The EU IP SOCRADES intents to build a complete automation system based on SOA. In the framework of this project the mapping of existing profile models to Web services is therefore investigated. The paper presents the migration steps starting from existing model descriptions to an example of a Web service based profile.