The number of complex ultrasonic applications is increasing. The range extends from distance measurement and the identification of obstacles to non-destructive material testing with phased arrays for air-coupled ultrasound. So-called 3D-printed waveguides are currently being developed for such technically complex applications. So far, adequate protection of the equipment against water and dust has been a problem, however, as many practical applications require the equipment to function even under extremely demanding environmental conditions

The Technical University of Darmstadt in Germany has now addressed this problem in a research project and carried out tests with our liquid and dirt-repellent Acoustic Cloth 2.0, among other things. The results presented by Professor Mario Kupnik’s research team in September 2020 during the 2020 IEEE International Ultrasonics Symposium (IUS) in Las Vegas* demonstrate the high suitability of acoustic material 2.0 for protecting waveguides. “We (…) demonstrate that the protection via hydrophobic fabric works excellent, i.e. without any significant drawbacks. Beam steering stays fully functional and the reduction of sound pressure level is only in the order of 1.5 dB. However, now the array can be used in real world applications,” the researchers conclude.  

phased arrays for air-coupled ultrasonic applications using's 2.0 fabric as a protection layer
Acoustic Cloth 2.0 as a protection layer for air-coupled waveguide ultrasonic phased arrays

Further details on the TU Darmstadt website

* M. Rutsch, G. Allevato, J. Hinrichs and M. Kupnik, “Protection layer for air-coupled waveguide ultrasonic phased arrays,” 2020 IEEE International Ultrasonics Symposium (IUS), Las Vegas, NV, USA, 2020, pp. 1-4, doi: 10.1109/IUS46767.2020.9251728.