Airborne ultrasonic image generation with biomimetic sonar head

This work presents the results of airborne ultrasonic image generation based on biomimetic sonar heads. Ultrasonic images refer to the representation of the environment with the help of ultrasonic waves and based on sonar principle. The generation of ultrasonic images is based on the classical methodology of the sonar, having target detection and classification purposes as main applications. An element of the image (which could be assimilated as pixel) has the intensity proportional to signals reflected by the surface of objects in the explored environment. Sonar heads with biomimetic functional behaviour (i.e. having one emitter and two receivers) were built. The key motivation in deploying such sonar heads is efficiency, that is, simplicity combined with acceptable performances based on ultrasonic image processing. Simplicity is related to modularity and portable structure, in the sense of computer´s portability. Biomimetism has a double meaning, by the structure of the sonar head and by the nature of the exploring algorithms (which use observations on bat behaviour). This work considers airborne ultrasonic images at distances less than one metre and with fixed working frequency (40 kHz). The preliminary results show the feasibility of the approach and consolidate a research direction focused on navigation based on airborne ultrasonic image processing.