Intelligent sensors and actuators

This article introduces the concepts of intelligent sensors and actuators. First introduced in the 1980s, these new devices have benefited from numerous advances in microelectronics and the development of communication systems, in particular field networks. These developments led to the integration of new functions into sensors and actuators, including communication, and the emergence of what has come to be known as "intelligent sensors and actuators": "intelligent" being, in fact, a mistranslation of "smart", in the sense of "pleasant to use". Since then, the adjective "intelligent" has become commonplace, and any object that incorporates a little electronics and software becomes intelligent: intelligent buildings, intelligent cars, intelligent skis...

After a presentation of the various projects, which have enabled us to identify user needs and the solutions to be provided, we felt it important to summarize the evolution of automated systems. The processing distribution possibilities offered by microelectronics enable sensors and actuators to extend their initial function (measuring for a sensor, acting for an actuator) to include participation in certain functions previously performed by the central control system. Functional and then hardware architecture are developed. Since one of the essential functions of intelligent instruments is communication, the problems linked to the choice of networks (field of application, type of network, interoperability, etc.) are presented. Finally, operating safety aspects are discussed in detail, before some examples of industrial applications are given.