AUVAC

Phased Array Velocity Sensor Operational Advantages and Data Analysis

Abstract

In recent years the underwater navigation industry has expanded into more diverse and unique applications requiring a greater capability from its platform sensor set. Teledyne RD Instruments has answered the demand with a new patented Phased Array technology to be used as part of the growing Doppler Velocity Log and Acoustic Doppler Current Profiler Product Lines. This new technology derives a fundamental set of advantages over the standard Piston Array. It exhibits how the new Phased Array utilizes a single array transducer composed of multiple elements where four individual acoustic beams are electronically formed at their defined angles. In contrast the existing piston transducer technology utilizes the four individual ceramics where each beam is projected at its respective mounting angle. This yields the opportunity to increase the size of the single array while reducing the overall transducer size giving way for the characteristics which provide for operational improvement.

Achieving High Navigation Accuracy Using Inertial Navigation Systems in Autonomous Underwater Vehicles

Abstract

This paper presents a summary of the current state-of-the-art in INS-based navigation systems in AUVs manufactured by Bluefin Robotics Corporation. A detailed description of the successful integrations of the Kearfott T-24 Ring Laser Gyro and the IXSEA PHINS III Fiber Optic Gyro into recent Bluefin Robotics AUVs is presented. Both systems provide excellent navigation accuracy for high quality data acquisition. This paper provides a comprehensive assessment of the primary advantages and disadvantages of each INS, paying particular attention to navigation accuracy, power draw, physical size, and acoustic radiated noise. Additionally, a brief presentation of a recently integrated Synthetic Aperture Sonar system will be used to highlight how critical a high-performance INS is to hydrographic, mine countermeasures, and other SAS applications.

Autonomous observations of the ocean biological carbon pump.

Abstract.

Prediction of the substantial biologically mediated carbon flows in a rapidly changing and acidifying ocean requires model simulations informed by observations of key carbon cycle processes on the appropriate spatial and temporal scales. From 2000 to 2004, the National Oceanographic Partnership Program (NOPP) supported the development of the first low-cost, fully autonomous ocean profiling Carbon Explorers, which demonstrated that year-round, real-time observations of particulate organic carbon (POC) concentration and sedimentation could be achieved in the world’s ocean. NOPP also initiated the development of a particulate inorganic carbon (PIC) sensor suitable for operational deployment across all oceanographic platforms. As a result, PIC profile characterization that once required shipboard sample collection and shipboard or shore-based laboratory analysis is now possible to full ocean depth in real time using a 0.2-W sensor operating at 24 Hz. NOPP developments further spawned US Department of Energy support to develop the Carbon Flux Explorer, a free vehicle capable of following hourly variations of PIC and POC sedimentation from the near surface to kilometer depths for seasons to years and capable of relaying contemporaneous observations via satellite. We have demonstrated the feasibility of real-time, low-cost carbon observations that are of fundamental value to carbon prediction and that, when further developed, will lead to a fully enhanced global carbon observatory capable of real-time assessment of the ocean carbon sink, a needed constraint for assessment of carbon management
policies on a global scale.

A Powerful Method for Petroleum Exploration: Real-time Undersea Mass Spectrometry

A unique cycloidal mass spectrometer, called TETHYS1, has been developed to explore dissolved hydrocarbon and atmospheric gases at ocean depths to 5,000 meters.