A new high frequency ultrasonic SONAR head for airborne applications

The paper presents a new version of the ROVIBAT (ROmanian VIrtual BAT) sonar head, based on airborne transducer module (ATM) with five discrete frequencies (40, 125, 200, 228 and 300 kHz). The sonar head is used for navigation of the robots and for ultrasonic image generation of the explored environment. The previous versions of the ROVIBAT heads, i.e. 00 to 04, have used a single working frequency (40 kHz). At each single frequency, an airborne ultrasonic image is obtained. The obtained image is not very rich in information, especially concerning the size and the type of the target´s surface. The final goal of the new sonar head is to improve the quality of the ultrasonic images by exploring multispectral image fusion techniques. Such fused images will be more useful for detection and classifying the contours and textures of the explored targets. The fixed frequency ultrasonic transducers from previous versions are replaced now by an airborne transducer module (ATM), which contains all five transducers. The characteristics of the module and the solution used to integrate this element in the structure of the ROVIBAT sonar head are presented and discussed in this work.