Ultralow-power standoff acoustic leak detection

TL;DR

This paper presents a low-power, remote acoustic leak detection device capable of identifying water leaks behind surfaces at over 10 meters distance, with potential applications for gas leak detection.

Contribution

The work introduces an autonomous, edge-processed acoustic leak sensor that operates at high frequencies, enabling reliable detection behind surfaces with minimal power consumption.

Findings

Detects water leaks at over 10 meters distance

Operates at 20-200 micro-Watts power range

Effective for leaks behind walls and surfaces

Abstract

An automated, standoff acoustic leak detection scheme has been designed, built, and tested. It merges the principles of glass breakage and smoke detection to alert for the presence of leaks emanating from pressurized plumbing. A simulated water leak flowing at 0.15 l/min has been reliably detected at a standoff distance of more than 10 m. The device is also effective at identifying the presence of leaks located behind surfaces such as walls, doors, floors, and ceilings. The anticipated application is as an autonomous, battery-powered, remote wireless node. All signal processing and analysis takes place on the edge with no need to stream audio data to the cloud. Sensor status is conveyed on-demand with only a few bytes of information, requiring minimal bandwidth. Power consumption is the range of 20--200 micro-Watts, depending on the amount of environmental noise and desired sensor latency. To attain optimum sensitivity and reliability, the hardware operates at acoustic frequencies well above the range of human conversations, making eavesdropping impossible. Development has been done with water escaping from pressurized plumbing, but the sensor concept can be used effectively to detect gas leaks.