Bio-Inspired Robotic Fish With Vision Based Target Tracking

The lionfish is an invasive species that out-competes and overcrowds native sh species along the eastern seaboard of the United States and down into the Caribbean. Lionfish populations are growing rapidly. Current methods of monitoring lionfish populations are costly and time intensive. A bio-inspired robotic fish was built to use as an autonomous lionfish tracking platform. Lionfish are tracked visually using an onboard processor. Five different computer vision methods for identification and tracking are proposed and discussed. These include: background subtraction, color tracking, mixture of Gaussian background subtraction, speeded up robust feature (SURF), and CamShift based tracking. Each of these methods were compared and their accuracy analyzed. CamShift based tracking is determined to be the most accurate for this application. Preliminary experiments for system identification and control design are discussed

Underwater Robots Part I: Current Systems and Problem Pose

International audienceThis paper constitutes the first part of a general overview of underwater robotics. The second part is titled: Underwater Robots Part II: existing solutions and open issues

Lossy compression and real-time geovisualization for ultra-low bandwidth telemetry from untethered underwater vehicles

Submitted in partial fulfillment of the requirements for the degree of Master of Science at the Massachusetts Institute of Technology and the Woods Hole Oceanographic Institution September 2008Oceanographic applications of robotics are as varied as the undersea environment itself. As underwater robotics moves toward the study of dynamic processes with multiple vehicles, there is an increasing need to distill large volumes of data from underwater vehicles and deliver it quickly to human operators. While tethered robots are able to communicate data to surface observers instantly, communicating discoveries is more difficult for untethered vehicles. The ocean imposes severe limitations on wireless communications; light is quickly absorbed by seawater, and tradeoffs between frequency, bitrate and environmental effects result in data rates for acoustic modems that are routinely as low as tens of bits per second. These data rates usually limit telemetry to state and health information, to the exclusion of mission-specific science data. In this thesis, I present a system designed for communicating and presenting science telemetry from untethered underwater vehicles to surface observers. The system's goals are threefold: to aid human operators in understanding oceanographic processes, to enable human operators to play a role in adaptively responding to mission-specific data, and to accelerate mission planning from one vehicle dive to the next. The system uses standard lossy compression techniques to lower required data rates to those supported by commercially available acoustic modems (O(10)-O(100) bits per second). As part of the system, a method for compressing time-series science data based upon the Discrete Wavelet Transform (DWT) is explained, a number of low-bitrate image compression techniques are compared, and a novel user interface for reviewing transmitted telemetry is presented. Each component is motivated by science data from a variety of actual Autonomous Underwater Vehicle (AUV) missions performed in the last year.National Science Foundation Center for Subsurface Sensing and Imaging (CenSSIS ERC

Towards autonomous localization and mapping of AUVs: a survey

Purpose The main purpose of this paper is to investigate two key elements of localization and mapping of Autonomous Underwater Vehicle (AUV), i.e. to overview various sensors and algorithms used for underwater localization and mapping, and to make suggestions for future research. Design/methodology/approach The authors first review various sensors and algorithms used for AUVs in the terms of basic working principle, characters, their advantages and disadvantages. The statistical analysis is carried out by studying 35 AUV platforms according to the application circumstances of sensors and algorithms. Findings As real-world applications have different requirements and specifications, it is necessary to select the most appropriate one by balancing various factors such as accuracy, cost, size, etc. Although highly accurate localization and mapping in an underwater environment is very difficult, more and more accurate and robust navigation solutions will be achieved with the development of both sensors and algorithms. Research limitations/implications This paper provides an overview of the state of art underwater localisation and mapping algorithms and systems. No experiments are conducted for verification. Practical implications The paper will give readers a clear guideline to find suitable underwater localisation and mapping algorithms and systems for their practical applications in hand. Social implications There is a wide range of audiences who will benefit from reading this comprehensive survey of autonomous localisation and mapping of UAVs. Originality/value The paper will provide useful information and suggestions to research students, engineers and scientists who work in the field of autonomous underwater vehicles

Reconfigurable AUV for Intervention Missions: A Case Study on Underwater Object Recovery

Starting in January 2009, the RAUVI (Reconfigurable Autonomous Underwater Vehicle for Intervention Missions) project is a 3-year coordinated research action funded by the Spanish Ministry of Research and Innovation. In this paper, the state of progress after 2 years of continuous research is reported. As a first experimental validation of the complete system, a search and recovery problem is addressed, consisting of finding and recovering a flight data recorder placed at an unknown position at the bottom of a water tank. An overview of the techniques used to successfully solve the problem in an autonomous way is provided. The obtained results are very promising and are the first step toward the final test in shallow water at the end of 2011

ROAZ and ROAZ II Autonomous Surface Vehicle Design and Implementation

International Lifesaving Congress 2007, La Coruna, Spain, December, 2007The design and implementation of the ROAZ and ROAZ II autonomous surface vehicles (ASV) is presented. These systems were developed at Autonomous Systems Lab, ISEP/IPP – Instituto Superior de Engenharia do Porto under a research program in marine robotics. With multiple applications either in river and estuarine environments or in the sea, the system applications in search and rescue operations are addressed and were taken in consideration for the overall system design. Mechanical design issues are discussed. Hardware, software and implementation status are described along with the control and navigation system architecture. The real time vision processing system is described and results are presented in operational scenario

Research Brief

Approved for public release; distribution is unlimited