2.1 History of the development of AUVs Development of AUVs goes back to the 1960s up to beginning of the current decade [1]. During the 1960s initial research was held about the utility of AUVs. Some vehicles were built to perform specific applications, such as data collection. Later, in the 1970s, some testbeds were developed by different universities and institutions. It was a time of important advancements in the development of AUVs. Some of the designed vehicles were: Special Purpose Underwater Research Vehicle (SPURV), developed by the Applied Physics Laboratory of the University of Washington. The vehicle was developed due to the need to collect oceanographic data from the Arctic regions [1]. L1 and L2, the first diving AUVs developed by the Institute of Marine Technology along with the Russian Academy of Sciences [1]. In the 1980s, advancements in computer technology affected the development of AUVs. Implementation of complex software and control algorithms was possible. In 1980, the first International Symposium on Unmanned Untethered Submersible Technology (UUST) was held at New Hampshire, USA with only 24 attendants. Nevertheless, by 1987 more than 320 people from different universities, companies, federal agencies and 9 countries attended the symposium. Various research programs started and it was clear that AUVs would become operational systems. During the 1990s AUVs testbeds turn into operational systems. They were able to accomplish a set of tasks according to defined goals. Many AUVs were internationally developed during this time and potential users emerged and contributed in the definition of mission tasks. At the beginning of the current decade the market for AUVs was defined. Nowadays, apart from the academic and research field, the AUV technology has been inserted into the commercial current of the ocean industry. Examples of AUVs that have been developed for commercial applications are [19]: Maridan 600 (M600), developed by Maridan A/S, Denmark. In 2001, De Beers Marine acquired an M600 to conduct surveys at depths of 110-150 meters for hard minerals off the coast of South Africa. Hugin 3000, developed by Kongsberg A/S, Norway for C & C Technologies, Inc, a U.S. based marine survey firm. It has conducted surveys for offshore oil and gas surveys in the Gulf of Mexico since 2001.

After these historic underwater vehicles, there have been many more submersiblesdeveloped and used operationally for a number of different tasks. With these submarines, camethe development of torpedoes. Torpedoes are truly the first (AUVs) Autonomous UnderwaterVehicles. Although there are a number of AUV-like systems that were considered prior to the1970s, most never were used for extended periods of time or discussed in open literature. Sincethat time a great deal of development has occurred.type of unmanned submersible is an Unmanned UntetheredVehicle(UUV). This untethered vehicle contains its own onboard power, but is controlled by aremote operator via some type of a communications link. An AUV is an undersea systemcontaining its own power and controlling itself while accomplishing a pre-defined task. Afurther distinction between the AUV and UUV is that the AUV requires no communicationduring its mission whereas the UUV requires some level of communication for it to complete itsassigned mission

A Brief Chronological History of AUV DevelopmentIt is informative to understand what has happed over the past few decades relative to thedevelopment of AUVs. It is clear that the process has led to a technology whose time hasarrived.Prior to 1970 - Special Applications of AUVs. Initial investigations into the utility of AUV systems.AUV development began in the 1960s. A few AUVs vehicles are built mostly to focusedon very specific applications / data gathering. There are not a great amount of published papersthat describe these efforts.1970 - 1980 - Explore the Potential of AUVs. Technology development; some testbeds built.During the 1970s, a number of testbeds were developed. The University of WashingtonAPL developed the UARS and SPURV vehicles to gather data from the Arctic regions. The University of New Hampshires Marine Systems Engineering Laboratory (now the AutonomousUndersea Systems Institute) developed the EAVE vehicle (an open space-frame AUV) inconjunction with a complementary effort undertaken at the US Navys facility in San Diego.Also at this time the Institute of Marine Technology Problems, Russian Academy of Sciences(IMTP, RAS) began their AUV program with the development of the SKAT vehicles, as well as,the first deep diving AUVs L1 & L2. Other AUV testbeds were also fabricated. This was a timeof experimentation with technology in hopes of defining the potential of these autonomoussystems. There were some successes and many failures. The vision shared by the developmentcommunity far exceeded the technology available to implement that vision. None the less, therewas significant advancement in AUV development.1980 - 1990 - Experiment with Prototypes. Advances in technology reinforce development efforts.. Proof of Concept (POC) prototypes are developed/tested/used.In the 1980s there were a number of technological advances outside of the AUVcommunity that greatly affected AUV development. Small, low power computers and memoryoffered the potential of implementing complex guidance and control algorithms on autonomousplatforms. Advances insoftware systems andengineering made it possibleto develop complex softwaresystems able to implement thevision of the systemdevelopers. Even with thesetechnological advances, itbecame quite clear that anumber of technologydevelopment problems had tobe solved if AUVs were tobecome operational systems.In 1980, the firstInternational Symposium onUnmanned UntetheredSubmersible Technology(UUST) was held in DurhamNew Hampshire, USATwenty-four technologistattended this meeting. By1987, the attendance hadgrown to more than 320people representing more than100 companies, 20Universities and 20 federal agencies. Nine countries were represented at the meeting. Most importantly in the USA, research programs were begun which provided significantfunding to develop proof of concept prototypes. The most published program was the effort atDraper Labs that led to the development of two Large AUVs to be used as testbeds for a numberof Navy programs. This decade was indeed the turning point for AUV technology. It was clearthat the technology would evolve into operational systems, but not as clear as to the tasks thatthose systems would perform.1990 - 2000 - Goal Driven Tech. Development. Broader based funding of technology development.. Many AUVs developed internationally. Users awake.During this decade, AUVs grew from proof of concept testbeds into first generationoperational systems able to be tasked to accomplish defined objectives. A number oforganizations around the world undertook development efforts focused on various operationaltasks. Potential users surfaced and helped to define mission systems necessary to accomplish theobjectives of their data gathering programs. This decade also identified new paradigms for AUVutilization such as the Autonomous Oceanographic Sampling System (AOSN) [Curtin] andprovided the resources necessary to move the technology closer to commercialization.2000 - 2010 - Commercial markets grow. First truly commercial productsbecome available.As this decade begins, theutilization of AUV technology for anumber of commercial tasks is obvious.Programs are underway to build, operateand make money using AUVs. Marketshave been defined and are being assessedas to viability. This will be the decadethat sees AUV technology move from theacademic and research environment intothe commercial mainstream of the oceanindustry. There are still technologicalproblems to be solved. The economicviability of the technology has still to be proven. The AUV must be proven in an operationalregime in order for the technology to continue its advance and for industry to embrace itspotential.

Fig. 1. The UK Natural Environment Council (NERC) Autosub6000 AUV, depth-rated to 6000m, can be equippedwith multiple payloads formarine geoscience research, including a highresolutionmultibeamechosounder,sub-bottomprofiler and sidescan sonar, a colour camera system, and Conductivity, Temperature, Depth (CTD) and electrochemical redox (Eh) sensors.The vehicle is 5.5 m long and has a dry weight of 1800 kg; it is capable of precision navigation and terrain following, and has a sophisticated collision avoidance system

Remus vehicle communicating with the LBLIntroductionAn Autonomous Underwater Vehicle (AUV) is a robotic device that is driven through the waterby a propulsion system, controlled and piloted by an onboard computer, and maneuverable inthree dimensions. This level of control, under most environmental conditions, permits thevehicle to follow precise preprogrammed trajectories wherever and whenever required. Sensorson board the AUV sample the ocean as the AUV moves through it, providing the ability to makeboth spatial and time series measurements. Sensor data collected by an AUV is automaticallygeospatially and temporally referenced and normally of superior quality. Multiple vehiclesurveys increase productivity, can insure adequate temporal and spatial sampling, and provide ameans of investigating the coherence of the ocean in time and space.The fact that an AUV is normally moving does not prevent it from also serving as a Lagrangian,or quasi Eulerian, platform. This mode of operation may be achieved by programming thevehicle to stop thrusting and float passively at a specific depth or density layer in the sea, or toactively loiter near a desired location. AUVs may also be programmed to swim at a constantpressure or altitude or to vary their depth and/or heading as they move through the water, so thatundulating sea saw survey patterns covering both vertical and/or horizontal swaths may beformed. AUVs are also well suited to perform long linear transects, sea sawing through thewater as they go, or traveling at a constant pressure. They also provide a highly productivemeans of performing seafloor surveys using acoustic or optical imaging systems.When compared to other Lagrangian platforms, AUVs become the tools of choice as the needfor control and sensor power increases. The AUVs advantage in this area is achieved at theexpense of endurance, which for an AUV is typically on the order of 8- 50 hours. Most vehiclescan vary their velocity between 0.5 and 2.5 m/s. The optimum speed and the correspondinggreatest range of the vehicle occur when its hotel load (all required power except propulsion) istwice the propulsive load. For most vehicles, this occurs at a velocity near 1.5 m/s.The degree of autonomy of the robot presents an interesting dichotomy. Total autonomy doesnot provide the user with any feedback on the vehicles progress or health, nor does it provide ameans of controlling or redirecting the vehicle during a mission. It does, however, free the userto perform other tasks, thereby greatly reducing operational costs, as long as the vehicle and theoperator meet at their duly appointed times at the end of the mission. For some missions, totalautonomy may be the only choice; in other cases when the vehicle is performing a routinemission, it may be the preferable mode of operation.Bidirectional acoustic, radio frequency, and satellite based communications systems offer thecapability to monitor and redirect AUV missions worldwide from a ship or from land. For thisreason, semi-autonomous operations offer distinct advantages over fully autonomous operations.HistoryThe following presents highlights of some notable achievements in the history of AUVs. In theshort space and time available, it is unfortunately not possible to provide information on allsystems.The origin of AUVs should probably be linked to the Whitehead Automobile Fish Torpedo.Robert Whitehead is credited with designing, building, and demonstrating the first Torpedo inAustria in 1866. Torpedoes are named after the Torpedo fish, which is an electric ray capable ofdelivering a stunning shock to its prey. Whiteheads first torpedo achieved a speed of over 3.0m/s and ran for 700 m. The vehicle was driven by compressed air and carried an explosivecharge. If one ignores the fact that it carried an explosive charge, it might be considered the firstAUV.The need to obtain oceanographic data along precise trajectories and under ice motivated StanMurphy, Bob Francois, and later Terry Ewart of the Applied Physics Laboratory of theUniversity of Washington to begin development of what may have been first true AUV in thelate 1950s. Their work led to the development and operation of The Self Propelled UnderwaterResearch Vehicle(s) (SPURV). SPURV I, became operational in the early 60s and supportedresearch efforts through the mid 70s. SPURV I displaced 480 kg, and could operate at 2.2 m/sfor 5.5 hours at depths to 3 km. The vehicle was acoustically controlled from the surface andcould autonomously run at a constant pressure, sea saw between two depths, or climb and dive atup to 50 degrees. Researchers used the vehicle to make CT measurements along isobaric lines insupport of internal wave modeling [1]. The vehicle was used later in the 70s to supportobservations of Horizontal and Vertical Diffusion using a dye tracer at depths to 1 km. Thevehicle was able to track the dye plume 66 hours after the dye was released [2]. SPURV II wasmore capable than SPURV I, and was used to study the dispersion of submarine wakes using adye tracer during the 70s and 80s. There were over 400 SPURV deployments.The Naval Ocean System Center, now SPAWAR, began development of the AdvancedUnmanned Search System (AUSS) in 1973 in response to the sinking of the USS Thresher, theUSS Scorpion, and the H bomb loss of Palomares. The vehicle was launched in 1983, andreports and publications on the system were still in press in the 90s. AUSS displaced 907 kg,carried 20 kw-hours of energy in silver zinc batteries, and was rated to 6 km. It had an acousticcommunication system that transmitted video images through the water. AUSS completed over114 dives, some to 6 km. The concept of using multiple free swimming vehicles to improvesystem performance can be traced to the development of this system. This work was completedsome time in the early 80s. [5]IFREMERs Epulard was designed in 1976, assembled by 1978, and was fully operational by1980. Epulard was the first 6 km rated acoustically controlled AUV that supported deep oceanphotography and bathymetric surveys. The vehicle maintained a constant altitude above thebottom by dragging a cable. Epulard completed 300 dives, some to 6 km, between 1970 and1990 [3].According to Busbys 1987 Undersea Vehicle Directory, there were six operational AUVs andan additional 15 other vehicles that were considered to be prototypes or under construction by1987. During this period, AUVs were called un-tethered (autonomous) ROVs, and theacronym AUV stood for Advanced Underwater Vehicle, a vehicle under development by theU.S. Defense Advanced Research Projects, which was completed in 1984. The origin of the the late 80s [4].During the 90s, there was a rekindling of interest in AUVs in academic research.The Massachusetts Institute of Technologys Sea Grant AUV lab developed six Odysseyvehicles during the early 90s. These vehicles displaced 160 kg, could operate at 1.5 m/s for upto six hours, and were rated to 6 km. Odyssey vehicles were operated under ice in 1994, and to adepth of 1.4 km for 3 hours in the open ocean in 1995 [6]. Odyssey vehicles were also used insupport of experiments demonstrating the Autonomous Ocean Sampling Network during thisperiod [7].WHOIs Autonomous Benthic Explorer (ABE) was also developed during the early 90s andcompleted its first scientific mission in 1994. ABE displaces 680 kg and can operate for up to 34hours to depths of 5 km, and typically travels at about 0.75 m/s. ABE carries six thrusters,making it a highly maneuverable vehicle in all three dimensions. These capabilities make ABEan excellent platform to perform near bottom surveys in rough terrain. ABE has completed over80 dives in support of science; one dive lasted for 30 hours at 2.2 km. Its deepest dive to datewas to 4 km [7].International Submarines Engineering, Ltds Theseus was developed during the early 90s for theU.S. and Canadian defense establishments. Theseus displaces 8,600 kg, and could operate at 2m/s for 100 hours to depths of 1 km. The vehicle successfully laid 190 km of fiber optic cableunder ice in 500 m of water in 1996; total mission length was 365 km and was completed in 50hours [9].WHOIs REMUS vehicle was developed in the late 90s to support scientific objectives at theLEO-15 observatory in Tuckerton, NJ, with funding from NSF and NOAA. REMUS completedits first scientific mission in 1967. The vehicle displaces 36 kg and can operate for up to 20 hoursat 1.5 m/s and to a depth of 100 m. There are currently over 50 REMUS vehicles in 20 differentconfigurations that are being independently operated by nine universities, three US Navylaboratories, one British defense laboratory, and three branches of the US Navy. Hundreds ofpeople have been successfully trained in the use of REMUS vehicles. It is not possible todetermine how many missions have been performed by REMUS. The longest REMUS missionlasted 17 hours. The vehicle traveled 60 km at 1.75 m/s at a maximum depth of 20 m off thecoast of NJ at the LEO-15 observatory [10].South Hampton Oceanography Centers Autosub was developed during the early 90s to providescientists with the capability to monitor the oceans in new ways. Autosub completed its firstscientific mission in 1998. The vehicle displaces 1700 kg, and can travel for up 6 days at 3 knotsat depths up to 1.6 km. Autosub has completed 271 missions, totaling 750 hours and covering3,596 km. Its deepest dive was to 1 km.; its longest mission lasted 50 hours [11]. In 1998, theUK National Environmental Research Council provided 2.6m pounds in grants and trainingawards for use with the Autosub. These grants stimulated a great deal of interest in the scientificcommunity. The turn of the century ushered in the first commercial enterprise to offer deep water (3 km)AUV survey services. C&C Technologies of Lafayette, Louisiana offers a Hugin 3000 AUV forcharter. The vehicle was manufactured by Kongsberg Simrad of Norway. The vehicle displaces1400 kg, and can operate at 4 knots for 40 hours utilizing an aluminum/oxygen fuel cell. C&CTechnologies has completed over 17,702 km of (paid for) geophysical mapping, some to 3 km,since the vehicle was first offered in 2000. C&C Technologies also offers its clients interactivesoftware on their web site that permits them to monitor and direct the progress of the generationof charts that are being made aboard the survey ship that is supporting the AUV survey. [12].