Intelligent Actuators for Low Cost Automation

Abstract

Most of the problems which occur during the operation of complex production systems are linked with faulty sensors or actuators. Such faults have a considerable effect on the safety of the system (non detected faults) or on its productivity (false alarm, stopping the operation of the system).In a great number of cases, it is possible to make use of locally available informations, and to detect actuators faults via local treatment of information. This approach needs no relevant modification of the whole system but makes use of the redundancy which already exists in the actuator’s instrumentation. In that sense, we develop a supervision procedure based on the description of the actuator by means of state graphs. This procedure gives as an output the actual state of the actuator as well as the list of its faulty instruments.We propose a functional architecture for smart actuators, which integrates not only the supervision function but also generates the necessary informations to meet the needs expressed by the different operators which have to manage the system.