Underwater localization system for marine seismic airgun arrays validated through robotics

Marine seismic surveys rely on the precise localization of seismic airguns to ensure high-quality data acquisition. The current state-of-the-art systems for airgun localization, such as Ultra-Short Baseline (USBL), Long Baseline (LBL), and GPS-aided and hybrid systems, provide reliable positioning but are often costly, operationally complex or limited to surface tracking. To address these limitations, this research presents a novel, cost-effective, and robust underwater localization system designed explicitly for real-time trajectory tracking of seismic airguns. The proposed system integrates a low-cost Inertial Motion Unit (IMU), an open-source, modular, and low-power acoustic modem, and a depth sensor, employing an Extended Kalman Filter (EKF) using Robot Operating System (ROS) for the development of the sensor fusion and localization algorithm. The system achieves a position accuracy within 0.3–2 m, meeting the tolerances required for seismic surveys. Compared to USBL + INS and GPS-aided systems, the proposed system provides comparable precision while significantly reducing deployment complexity and operational costs. Unlike LBL systems, it does not rely on pre-installed seabed transponders, enhancing adaptability to different operational environments. Furthermore, its capacity to operate underwater without surface GPS dependency overcomes the limitations of existing systems in deep-sea or complex acoustic environments. The system is expected to enhance marine seismic data quality by enabling real-time positioning tracking, reduce marine seismic exploration times, and mitigate potential environmental impacts on marine ecosystems. This innovation bridges the gap between precision, affordability, and environmental sustainability in marine seismic exploration, making it a promising alternative for integrating trajectory position estimates of airguns into seismic survey workflows, helping to enhance the efficiency and effectiveness of marine seismic surveys worldwide.