the pipeline leak detector is a mobile device having a pressure sensor array for travel within a fluid pipeline for leak detection in the pipe wall . the sensor array is positioned close to the internal surface of the pipe wall and rotates circumferentially about the surface of the pipe wall as the device travels through the pipe , thus describing a helical path along the pipe wall to cover the entire internal surface of the pipe wall with a minimal number of sensors . the sensors comprise tubes with conical mouths , and flexible members and strain gauges within the tubes . pressure changes due to leaks cause the flexible members to move , with the strain gauges sending signals to a central processor to indicate a leak . the device is supported by a drive wheel , a driven wheel , and an idler wheel bearing against the internal surface of the pipe and evenly circumferentially spaced .