Localization of compressed air leaks in industrial environments using
service robots with ultrasonic microphones
T. Guenther, and A. Kroll. 32nd European Conference on Acoustic Emission Testing, page 173--182. Prague, Czech Republic, European Working Group on Acoustic Emission, VUTIUM Brno, (7. -9. September 2016)
Abstract
Compressed air is a widespread but costly energy carrier. Leaks account
for 10 compressed air consumption in production facilities and their
removal offers high potential for cost reduction. The turbulent flow
from a leak causes broadband acoustic emissions. These are exploited
for leak detection using a narrowband ultrasonic microphone that
is insensitive to audible noise. A parabolic mirror or an acoustic
horn is utilized to enhance the directivity and the received signal
power of the microphone. The microphone is mounted on mobile service
robots. In the project "Robotair" an automated guided vehicle (AGV)
and a remotely controlled micro aerial vehicle (MAV) were used for
robotized inspection of production facilities. In order to detect
leaks, predefined areas are scanned. A leak is detected and localized
based on the sensed peak amplitude of the ultrasound signal. The
corresponding pose of the sensor facing the leak is determined based
on the selflocalization of the robot. Leak localization is carried
out by triangulation of two sensor poses. Tests were conducted in
an automobile production facility to evaluate the performance of
the system. A leak was placed in an assembly line and multiple measurements
were taken from two positions with the AGV and the MAV. The leaks
were successfully detected and localized.