An Intelligent Ultrasonic Sensor for Ranging in an Industrial Distributed Control System

Abstract In this paper, an intelligent instrument for ranging purposes is described. It is based on the precise determination of the time of flight (TOF) of an ultrasonic pulse to evaluate the distance from an object. Ultrasonic sensors offer high reliability, wide measurement ranges, reduced sensitivity to EM noise, and the ability to operate in dusty and dirty environments. This instrument uses digital signal processing techniques in order to improve the accuracy of the measurements and to increase its capabilities. The digital signal processing is managed by an 8-bit microcontroller. The communication tasks through a fault-tolerant real-time LAN, are carried out by an specific processor in order to discharge the main processor.