AUV Applications Within E&P

Abstract

Abstract In February 1999 Shell examined the current state of AUV development and evaluated the usefulness of the technology for enhancing our ability to explore for and produce offshore oil and gas. Our study addressed four questions:Can AUV's resolve our present problems?Will AUV's deliver a business benefit?Does AUV technology lend itself to easy implementation in the near future? AndWhat actions can we take to help catalyze the market? Two separate types of AUV were identified for use within E&P: a survey class vehicle for data acquisition, and an engineering class vehicle for underwater intervention. For each type, this paper will describe the answers to the questions above; addressing the problems we hope to solve, our estimate of the feasibility of using AUV's to solve them, the business case for AUV's, and our analysis of the state of the market today. A description of desirable attributes will be given for each type of AUV for a minimal case and a realistic ideal case. Introduction In late 1998 and early 1999 Shell conducted an internal study of Autonomous Underwater Vehicle (AUV) technology. The purpose of the study was to evaluate the usefulness of the technology for enhancing our ability to find and produce offshore oil and gas. As the name implies, an AUV is a robotic vehicle capable of independent actions underwater. Using sophisticated artificial intelligence software integrated with sensors that give it an awareness of its surroundings, the vehicle can carry out pre-programmed tasks and react to unexpected conditions. We identified two separate types of AUVs for use within E&P. The first is the survey class vehicle for seabed data acquisition and the second is a work class vehicle for underwater inspection, repair, and maintenance (IRM). For each type of AUV, we examined four questions:Can AUV's resolve our present problems?Will AUV's deliver a business benefit?Does AUV technology lend itself to easy implementation in the near future (5 years)?What actions are necessary to catalyze the market? Seabed Survey Problem The use of appropriate seabed survey data affects the cost of offshore developments by providing information necessary for correct design and installation. Good survey data ensures that the local environment is fully understood so unnecessary safety factors are not incorporated into design. The data also helps to ensure minimal environmental impact and that there are no unforeseen hazards. Survey data should allow for interpretation and identification of seabed morphology, natural and man-made seabed features, seabed soils, subsurface soils and features, and subsurface hazards. Data necessary to make these interpretations are obtained from a variety of sensors such as swathe bathymetric systems, sidescan sonar, and subbottom profiler. Additionally, magnetometer data and coring or sample data are used. Other information about the sensor platform and immediate environment is also needed to correctly use the data obtained from these sensors. The location, orientation, and attitude of the sensor must be measured.