A novel technique for dynamic alignment of ultrasonic transducers in real-time non-destructive testing

Ultrasonic non-contact inspection methods require the correct alignment of test probes before return signals (echoes) are acquired. However, for critical remote applications, such as pipeline inspection, there are no accurate means of achieving this objective, and hence the accuracy and full potential of ultrasonic inspection is not realized. In this paper, a novel sensing technique to detect angular misalignment of a test probe with a view to ensure automatic alignment of the probe with the target is presented. The technique is based on analyzing the waveform features of the received signals. In this regard, a theoretical formulation concerning the applicability of the method is first reported, followed by a detailed practical study. The technique could be employed for automatic alignment of the test probes in remote ultrasonic inspection.