Transactions on Systems, Signals and Devices: Volume 8 : Issues on Sensors, Circuits & Instrumentation

In this paper the authors present a mechatronic device consisting of an array of ultrasonic sensors pointed by a servo motor in order to scan two smooth orthogonal-connected surfaces.The motor rotation is controlled in such a way as to acquire the sonar output data in each rotation step and to connect the distance measures with the relating shaft positions. When a large beam is propagated at the intersection between the surfaces, the sonar readings are corrupted by the effect of multiple reflections because the wave returns back after striking both the planes. The use of powerful mathematical tools and the analysis of a physical indicator based on the ultrasonic full waveform energy allow detection of the critical region, where the reflection is not specular. The proposed approach permits to reconstruct the obstacle by using the Fuzzy C-Means (FCM) clustering and the RANdomSAmple Consensus (RANSAC) fitting.For the sake of investigating the applicability of this new strategy, two different laboratory experiments are conducted by firstly propagating ultrasonic waves toward wooden surfaces and successively toward the same surfaces covered by silver foils. The good results are shown in both the considered cases.