A Low-cost Distributed Measurement System based on Gas Smart Sensors for Environmental Monitoring

In this paper we describe the structure of a multiprocessor control system for a gas sensing array, inspired to the IEEE 1451 standard. The system (Smart Transducer Interface Module, STIM) features a simplified Transducer Independent Interface (TII) based on a 3-wire RS232 communication and is conceived as a cluster between identical monosensor subsystems and a central Controller. After a brief illustration of the modular system architecture, an overview on the basic monosensor modules and of the simplified TII will be given. Then, the design and implementation of a gateway acting as an interface between the system and the Ethernet (Network Capable Application Processor, NCAP) will be described. Finally, experimental results will be presented.