AUVAC

UUST 2013

Final Agenda

Sabertooth a Seafloor Resident Hybrid AUV / ROV System for Long Term Deployment in Deep Water and Hostile Environments.

Increasing use and complexity of subsea installations has put focus on the costs of maintaining these systems. In addition, access to these systems is sometimes limited by adverse weather and ice conditions. Conventional methods for intervention, maintenance and repair (IMR) using surface ships and ROV’s are very expensive furthermore response and mobilization times can be fairly slow.

To address this Saab Underwater Systems has developed a hovering Hybrid AUV/ROV system to remotely perform IMR without or strongly reduced need for a supporting ship. This system is based on the Double Eagle SAROV, a hovering Hybrid AUV/ROV in production for the military market and proven components from Saab Seaeye ROV product range.

This paper will present the Seaeye Sabertooth subsea resident AUV/ROV system, its concept of operation, design and the cooperation project between Saab and Aker Solution. It will also present the ongoing Sabertooth tests and trials conducted together with Tecnomare and Chevron.

Autonomous Transient Ocean Event Monitoring (ATOEM)

A novel conceptual design is presented for a research platform for Autonomous Transient Ocean Event Monitoring
(ATOEM). In simplest form, ATOEM would be an autonomous diesel-electric submarine of conventional design, but stripped of all of its requirements for human occupation and life support, and whose “torpedo” tubes would instead be loaded with a variety of AUV configurations (e.g., benthic, photic zone and midwater) capable of autonomous docking with the “mother ship”. Global deployment of a large fleet of modular, low-cost, highly-manufacturable ATOEM
platforms has the potential to transform oceanographic research by providing coordinated, comprehensive, time-series, spatiotemporal measurements of all key ocean properties on an unprecedented scale.

SUB-ICE EXPLORATION OF AN ANTARCTIC LAKE: RESULTS FROM THE ENDURANCE PROJECT

Abstract

The ENDURANCE autonomous underwater vehicle was developed and deployed to explore and map a unique environment: the waters of Lake Bonney in Taylor Valley, one of the McMurdo Dry Valleys of Antarctica. This permanently ice-covered lake presented several unique challenges and opportunities for exploration and mapping with an AUV. ENDURANCE was successfully deployed in the west lobe of Lake Bonney in the 2008-2009 and 2009-2010 austral summer seasons, completing the rst full synoptic 3-D chemical prole and high-resolution 3-D geometric mapping of such a body of water. ENDURANCE successfully traversed the entire 1 km x 2 km lobe of the lake, including successful automated spooling of a science payload and automated docking into a deployment/recovery melt hole 0.25 m larger in diameter than the vehicle.

A Mission Oriented Metric to Assess the Benefits of Biologically Inspired Propulsion

In this study, we quantify the potential mission specific benefits of biomimetic propulsion as a function of environmental conditions and operational requirements for a small unmanned underwater vehicle (UUV) mission. The benchmark mission requires the UUV to persist in shallow water for 24hr within a specified radius around the desired station, preceded and followed by a 40km transit

The achievable time on station for the nominal vehicle using biologically inspired propulsion is compared to that of the same vehicle using currently available thrusters. The comparison is carried out across a range of sea-states, with varying requirements for station keeping precision, and with a range of assumptions about the performance improvements provided by biomimetic propulsion. The expected magnitude and frequency of wave disturbances in shallow water are generated using U.S. Army Corps of Engineers guidelines for harbor design and construction.

If biomimetic propulsors can deliver on the promise of significantly improved effectiveness in generating low speed maneuvering forces, fin propelled vehicle can perform a high precision 24 hour station keeping mission in 3x higher waves than the thruster propelled vehicle. In rough conditions, the fin propelled vehicle can perform the mission with 10x higher precision.

Development of a Magetometry System for an Underwater Glider

The development of a magnetometry system for an underwater glider is detailed in this paper. The system is designed for low noise, low sampling rates and high accuracy measurements. The integration progress into a 200 m Slocum Electric glider is presented in addition to an evaluation of the electrical and system noise levels. A calibration algorithm is evaluated for correcting sensor errors as well as hard and soft magnetic effects due to the glider.

Feature Based Navigation for a Platform Inspection AUV

Under the Offshore Platform Inspection System (OPIS) program, an LM AUV, the MARLIN(TM), is being outfitted with a mission package which includes a 3D imaging sonar and processors in order to inspect and build 3D models of subsea structures, and to detect large scale damage to these structures relative to a reference model. A key component of this model building and change detection functionality is a process by which sonar data is aligned to the reference model and the vehicle/sensor pose is recovered. An interesting by-product of this is the use of this recovered pose for feature based navigation. This paper presents a method to fuse the estimated pose from an inertial navigation system with the pose recovered from the alignment of sonar data with a reference model, and the use of this fused estimate in vehicle guidance, 3D model building and change detection, and to improve inertial navigation performance. While the technology is developed for an underwater platform inspection system, the methods have broader applicability. Results are presented to demonstrate the performance of the feature-based navigation system.

Towards Amphibious Robots: Asymmetric Flapping Foil Motion Underwater Produces Large Thrust Efficiently

The development of amphibious robots requires actuation that enables them to crawl as well as swim; sea turtles
are excellent examples of amphibious functionality, that can serve as the biomimetic model for the development of amphibious robots.

In this paper we have implemented the observed swimming kinematics of Myrtle, a green sea turtle Chelonia Mydas residing in the Giant Ocean Tank of the New England Aquarium, on the 1.5-meter long biomimetic vehicle Finnegan the RoboTurtle. It is shown that these kinematics result in outstanding performance in (a) rapid pitching, and (b) rapid level turning. The turning radius for the rigid hull vehicle is 0.8 body lengths, a remarkable improvement in turning ability for a rigid hull vehicle.

Still Finnegan’s performance lags the live turtle’s performance by about 20%. Careful observations have shown that turtles employ a fin motion in-line with the direction of locomotion; this degree of freedom was not available to the Finnegan fins, as presently designed. Experimental tests on a flapping fin equipped with this third degree of freedom have shown that the in-line motion enhances the fin’s performance.

This hydrodynamic result is doubly beneficial to an amphibious robot, because it allows for further enhancements in the hydrodynamic function of fins, while the in-line motion allows the same fins to be used for crawling on land.

Hovering Autonomous Underwater Vehicle – System Design Improvements and Performance Evaluation Results

The Hovering Autonomous Underwater Vehicle (HAUV) was initially jointly developed by Bluefin Robotics and the Massachusetts Institute of Technology for ship hull inspection under Office of Naval Research (ONR) funding. In 2008, under PMSEOD’s “Explosive Ordnance Disposal Hull Unmanned Underwater Localization System” program (EOD HULS), Bluefin conducted a major vehicle redesign in order to improve the system’s performance and bring it up to the EOD HULS specification. The EOD HULS HAUV system consisting of two vehicles and topside / support equipment was delivered in October 2008. It underwent the Engineering Evaluation phase of the Requirement Compliance Test and Evaluation (RCT&E) of the EOD HULS acquisition program by the Government in December 2008 in San Diego California. It is currently undergoing User Operational Evaluation with the Navy’s Mobile Diving and Salvage Unit 2 (MDSU-2) in Little Creek Virginia.

Design and Deployment of a 3D Autonomous Subterranean Submarine Exploration Vehicle

The NASA Deep Phreatic Thermal Explorer (DEPTHX) project is developing a fully autonomous underwater vehicle intended as a prototype of the Europa lander third stage that will search for microbial life beneath the ice cap of that Jovian moon. DEPTHX has two principal objectives: First, to develop and test in an appropriate environment the ability for an un-tethered robot to explore into unknown 3D territory, to make a map of what it sees, and to use that map to return home; and second, to demonstrate that science autonomy behaviors can identify likely zones for the existence of microbial life, to command an autonomous maneuvering platform to move to those locations, conduct localized searches, and to autonomously collect microbial life in an aqueous environment. The concept and prototypes are being tested in an unusual terrestrial analog that presents many of the likely morphologic regimes where life may exist on Europa: the 300- meter-deep (or more) hydrothermal cenote of Zacatón, Mexico, which contains diverse microbial mats, but remains uncharted, both spatially and biologically.

In this presentation we summarize the final vehicle architecture and control systems approach to autonomous exploration in fully 3D environments in which apriori knowledge of the environment is non-extant and for which there exists no external navigation system. The latest field work at Cenote La Pilita will be presented describing the February 5, 2007 mission during which DEPTHX became the first fully autonomous cave exploring robot.

DESIGN OF AN UNDERWATER VEHICLE FOR SUBTERRANEAN EXPLORATION

The NASA Deep Phreatic Thermal Explorer (DEPTHX) project is developing a fullym autonomous underwater vehicle intended as a prototype of the Europa lander third stage that will search for microbial life beneath the ice cap of that Jovian moon. DEPTHX has two principal objectives. The technology goal is to develop and test in an appropriate  environment the ability for a bot to explore into unknown 3D territory, to make a map of what it sees, and to use that map to return home. The science goal is to demonstrate that silicon intelligence can autonomously identify and collect microbial life in an aqueous environment.

The concept and prototypes will be tested in an unusual terrestrial analog that presents many of the likely morphologic regimes where life may exist on Europa, including irregular vertical surfaces, an open water column, floor sediments, and potential hydrothermal vents. The site is the 330- meter-deep (or more) hydrothermal cenote of Zacatón, Mexico, which contains diverse microbial mats, but remains uncharted, both spatially and biologically. The site offers an extraordinary opportunity to test the principles and hardware under development.

In this presentation the authors will summarize the overall vehicle architecture and control systems approach to autonomous mobility in fully 3D environments in which apriori knowledge of the environment is nonextant. The latest field work at the Zacaton cenote using a drop sonde variant of the DEPTHX vehicle core navigation components will be presented along with the current 3D map to -280m, created by co-registration of LADAR and sonar data.

SAUV II High Level Software Architecture

In January of 2003, the Autonomous Undersea Systems Institute (AUSI) joined with Falmouth Scientific, Inc. (FSI) and Technology Systems Inc. (TSI) to develop the second generation Solar powered Autonomous Underwater Vehicle (SAUV) II. The first generation SAUV was developed by AUSI along with the Institute of Marine Technology Problems (IMTP) [Ageev et. al., 2001] and served as a proof of concept for solar re-powering of an AUV.

The SAUV II development effort has been a team based program, where FSI focused on the vehicle hardware and its associated low level subsystem software, TSI focused on the user interface, and AUSI focused on program management and the development of the onboard high level mission/system software. In this manner, a diverse set of talents was brought together to realize the SAUV II design.

This paper will describe what we have named the SAUV “production” architecture, which has evolved during the past two and a half years. It will describe the various software modules and identify the functional components of the system that are controlled by the high level vehicle software. The paper will also describe the insights that resulted from in water testing and the impact that those insights have had on the overall system architecture.

Solar Powered Autonomous Vehicle Development

To meet the rapidly expanding requirements for Autonomous Underwater Vehicles (AUVs), Falmouth Scientific, Inc. (FSI) is working in cooperation with the Autonomous Undersea Systems Institute (AUSI) and Technology
Systems Inc. (TSI) to develop a vehicle capable of long-term deployment and station-keeping duties. It has long been considered that AUV platforms, in-principle, could provide an effective solution for surveillance (security and
anti-terrorist), environmental monitoring and data portal (to sub-sea instruments) requirements, but limitations in battery life have limited AUV usefulness in such applications. The concept of a vehicle that would allow on-station recharging of batteries, using solar cells, has been presented as a means to significantly enhance the effectiveness of AUV platforms where long-term or ongoing deployment is required.

The Solar Powered AUV (SAUV) is designed for continuous deployment (weeks to months) without requirement for recovery for service, maintenance or recharging. The SAUV under development is designed as a multi-mission
platform to allow payload configuration by the end-user to optimize the SAUV for coastal/harbor monitoring, data portal (to moored sub-surface instruments) applications, or any other application where long-term deployment is
required. The SAUV is designed to reside on the surface while recharging batteries and then to execute its programmed mission. While on the surface the SAUV is designed to communicate via Iridium® satellite or RF communications link to upload collected data and to allow reprogramming of mission profiles.

Development of the SAUV has generated numerous engineering challenges in design of the solar recharge system, design of a propulsion/direction control system capable of handling the unique shape requirement, design of the telemetry system, and development of mission control algorithms that include surfacing and battery recharge requirements.

This paper discusses the details of unique SAUV design requirements, specific engineering solutions for hull, panel, battery, communication, charge control, navigation,

Experirences on actuator fault detection, Diagnosis and Accomodation for ROV’s,

Abstract
This paper addresses the problem of low cost actuator fault detection, diagnosis and accommodation for Remotely Operated Vehicles. The research is based on the analysis of the telemetry of Romeo, the overactuated ROV developed by C.N.R.-I.A.N., operating both in nominal and different failure conditions. Results demonstrate how the monitoring of the servoamplifiers’ I/O variables enables the detection and diagnosis of actuator faults for operating ROVs, supporting the pilot in making decisions on the realtime reconfiguration of the propulsion system. The integration of the servo-level FDDA module with a conventional navigation, guidance and control system is discussed. On the basis of experienced time-varying effects of operating failures, suitable models of the damaged actuators and algorithms for the generation of fault symptoms and alarms have been designed, implemented and satisfactorily tested on a large
amount of recorded ROV data. The conventional fault accommodation procedure based on the reconfiguration
of the vehicle’s thrust control matrix has been applied. The capability of Romeo of working in a reduced actuation configuration has been operationally demonstrated executing shallow water benthic missions for scientific users.

Open Ocean Operational Experience with the AUTOSUB-1 Autonomous Underwater Vehicle

Abstract
The Autosub-la autonomous underwater vehicle (AUV) designed, built and operated by the Southampton Oceanography Centre is a medium endurance, multipurpose sensor platform designed for marine science studies of the upper ocean. With a specified range of 250 km, operating at 3.8 kt, and a diving depth capability of 500 m the vehicle has completed 179 engineering and science missions in UK coastal waters, off the east coast of Florida and off Bermuda. This paper focuses on three key areas particularly important to AUVs operatingo n long missions in the deep or open ocean: the predictability of the primary cell energy supply, particularly its predictability; buoyancy changes in a vehicle without active buoyancy control and scientific sensor performance – the raison d’2tre for the vehicle. We draw upon the methods, observations and results from the 1998 Autonomous Vehicle Validation Experiment (AVVEX)
when Autosub- 1 a operated off Bermuda in August-September 1998.