Cooperative Acoustic Navigation Scheme for Heterogenous Autonomous Underwater Vehicles

Abstract

Oceans cover 71% of the earth's surface and contribute the largest reservoir of life on the earth. With more and more concern about the abounding and valuable ocean resources, these years have witnessed a remarkable growth in the wide range of underwater commercial activities for ocean survey, especially focusing on undersea exploration and exploitation, and even extensively for salvage operations related with disastrous accidents occurred undersea (Lapierre, 2006). There are three main kinds of vehicles recruited for underwater activities. Manned Submersibles and Manned Underwater Vehicles with good abilities of directly manoeuvring and in-situ observation, have been widely utilized in commercial activity and scientific research, and reached the zenith in the late 1960s and early 1970s. However, this critical systems with vital importance of crew aboard and complex handling system significantly cost so much. Then, Remotely Operated Vehicles (ROVs) still with human in the loop but not in the vehicle are successful substitutes, being low-cost vehicles piloting in deep water greater than 1000ft. Today, ROV becomes a well-established technology frequently used in the offshore industry, most notably in the commercial offshore oil and gas, nuclear, pipeline and cable industries. Nevertheless, the long umbilical cable, linked with the mother ship, greatly inhibits the speed of the ROV, requiring the mother ship equipped with deck gear capable of winding up this cable and significantly restricting ship movement while deployed. More recently, with the development of advanced underwater technology, Autonomous Underwater Vehicles (AUVs) are steadily becoming the next significative step in ocean exploration due to their freedom from the constraints of an umbilical cable. Nowadays there has been gradually growth in the AUV industry worldwide which would be on an unprecedented scale and AUVs will carry out interventions in undersea structures in the future (Whitcomb, 2000). Moreover, recent applications using Intervention Autonomous Underwater Vehicles (IAUVs), have demonstrated the feasibility of autonomous underwater manipulations (Xu et al., 2007), controlled via acoustic links, thus removing the parasite effects of the umbilical cable (http://www.freesubnet.eu). With