SHAPING THE DETECTION LOBE OF ULTRASONIC RANGING DEVICES

The detection lobe or radiation area of an ultrasonic ranging device i s of primary importance in almost any application of such measuring sy stems, but in some cases the form of the lobe makes its use in real sy stems difficult or even impossible. The use of focusing arrays of sens ors is difficult because of the large size of the transducers in air, the complexity of the processing devices and the slowness of the measu ring process. In this paper we present a new way of conforming the ope ration field of an ultrasonic sensor that allows almost any arbitrary form to be fixed within the range of the sensor. The application of th e system is studied in a sensor for blind people and in an obstacle de tection sensor for mobile robots.