The bursting of bubble wrap, if judiciously done, can help detect whether there is crap (or to put it more nicely: unexpected stuff) inside a pipeline. This new study tells about the problem and the possible, bubble-wrap-bursting way to deal with the problem:
“Electric-power free impulse point sound source generation system with bubble wrap bursting phenomena for simplified non-destructive testing,” Shuichi Yahagia, Toshiki Shimizu, Seiya Inadera, Itsuro Kajiwara, and Naoki Hosoya, Measurement, vol. 258, 2026, article 119192. (Thanks to Takeo Suzuki for bringing this to our attention.) The authors, at Tokyo City University, ISUZU Advanced Engineering Center Ltd., Shibaura Institute of Technology, and Hokkaido University, Japan, report:
Electric-power free impulse point sound source generation system with bubble wrap bursting phenomena for an economical and simplified non-destructive testing method is proposed. The sound characteristics generated by bursting bubble wrap, including uncertainty, reproducibility, and frequency response, are initially evaluated via excitation tests. A bubble wrap can generate an impulse sound with high-frequency components of up to 40 kHz and semi- directional characteristics. Then a monitoring system to detect foreign objects in pipes is constructed. The monitoring system consists of bubble wrap to yield an impulse excitation and a microphone to measure the sounds. Applying a wavelet transform to the obtained time-series data with and without a foreign object can determine the location of the foreign object with an error of approximately 2 %. This method is readily available, portable, and affordable.