Junction Detection Based on CCWT and MEMS Accelerometer Measurement

Abstract

Pipeline Junction (PJ) is an important component that to connect the two adjacent straight pipeline segments for the routed pipeline. And the azimuth and pitch angles of cylindrical-shaped Pipeline Inspection Gauge (PIG) are constant within each straight pipeline segment. Therefore, detecting the PJ accurately could provide constant azimuth and pitch angles updates for Micro-Electro-Mechanical System (MEMS) Inertial Measurement Unit (IMU) based pipeline surveying system in each straight pipeline segment. This paper proposes a PJ detection method by using Complex Continuous Wavelet Transform (CCWT) to analyze the accelerometer measurement data of PIG in inspected pipeline. At first, the simulated MEMS IMU data when PIG travels inside the pipeline is obtained by a tri-axial turntable and a wheel robot, respectively. Then, both raw and de-noised accelerometer measurement data are extracted and analyzed by CCWT to implement the PJ detection. Finally, the PJ detection result provides azimuth and pitch angles updates for MEMS IMU based PIG surveying system without extra cost.