Transforming Raw Subsea Sensor Data for Advanced Dynamic Positioning and Autonomous Functions in Real-Time for Asset Management and Remotely Operated Vehicle Operations

摘要

Oil and gas exploration is moving towards deeper waters,challenging geographical areas and dynamic working environments. This paper outlines the technology developments in an advanced control system embedding intelligent algorithms with sensor data in a closed loop,to perform various inspection,repair and maintenance(IRM)tasks autonomously on a workclass remotely operated vehicle(WROV).Original analysis and field trial results are presented. The data from the navigation sensors can be used to position and geo-reference the payload data,however,survey has relied upon expert piloting skills to maintain the WROV on a set course at a predetermined speed,heading and height from the seabed.In response to emergency situations,the equipment is hard to mobilise and the investment can be compromised if the WROV cannot be made to steer the course.This paper presents novel work in developing an autonomous control function suite integrated on a WROV to maintain a pre-laid course and offer a stable platform to gather data,and perform a task. Combined navigation functionality fuses data from GPS string,imaging sonars and a state-of-the-art phased array Doppler Velocity Log(DVL)with a Dynamic Positioning computer.Operators are equipped with the tools to survey and inspect their environment in a compact,easily deployable form factor. This development highlights vehicle and umbilical positioning,movement logging,advanced vehicle controls(sophisticated cruise,mission planning and object/target recognition modules)and increased reliability.The Dynamic Positioning computer translates high-level mission requirements from a surveyor into automatic thruster commands providing automatic inspection and survey.Results from a selection of trials conducted with a major subsea operator using the system will be shown.The results demonstrate improvements in WROV control during transit,station keeping and conducting simulated riser inspection –via easy-to-use human-machine interface.The advance controls offer significant reduction in time and costs,and increased reliability,compared to pilots performing operations manually. The technical industrial contributions of this technology are reduced training costs,mitigating lump sum risks by saving time in construction support operations,maintaining the quality and reliability of drill support operations,improving the quality of data for survey and IRM activities and providing better umbilical management.