[ LAUNCH AND RECOVERY ] • [ WINCHES ] • [ SUB-SEA TOOLS & COMPONENTS ] [ SHIPBOARD A-FRAMES ] • [ AUV SYSTEMS ] • [ PRESSURE VESSELS ] • [ LASER TECHNOLOGY ] • [ OFFSHORE CONTAINERS ] AUV SYSTEMS - THE OCEAN VOYAGER The Ocean Voyager AUV is a joint, internally funded, project between HBOI and Florida Atlantic University. It was developed for coastal (shallow water) missions and for testing or demonstrating new components and sensors. PHYSICAL CHARACTERISTICS The Ocean Voyager is a torpedo shaped, 21 inch diameter vehicle, consisting of 4 aluminum sections and 2 fiberglass sections. The two center aluminum sections make up the pressure hull. The remaining sections are flooded. Currently the fins extend beyond the 21 inch diameter envelope (40 inches overall). The maximum operating depth of the AUV is 500 feet, limited only by the simple, unstiffened aluminum hull. The vehicle displaces approximately 2700 lb. and weighs about 1800 lb. in air. PROPULSION The vehicle is currently propelled by a conventional brushless DC motor and nozzle and propeller assembly. This unit will be replaced by HBOI's patented high-efficiency, counter-rotating, Electric Ring Propeller (ERP). Provisions have been made for the addition of maneuvering thrusters to be added at a later date. POWER SOURCE The vehicle system power is supplied from a 48 VDC battery bank. Power for computer and sensor systems is supplied by separate 24 VDC battery supplies. OPERATING SYSTEM The vehicle's operating system is VxWorks, a high performance real-time system. On top of VxWorks, the control system architecture consists of task based distributed heterogeneous modules written in C. The Ocean Voyager's Intelligent Control System (ICS) contains modules to deal with the various tasks constituting any mission. These include a mission planner, autopilot, navigator, seeker, dead reckoner, annotated mapper, emergency handler, health monitor, and obstacle avoider. This low level control is implemented as a single module, operating at 8 Mhz. Commands are received in the form of set points for heading, depth, pitch and speed. Control is executed by a three axis fuzzy logic flight control system. COMMAND AND CONTROL The AUV main computer consists of low power, 3U-sized O+R boards on a VME bus with low power active termination. Currently there are two main processor boards, each consisting of a 16 Mhz 68020 with an FPU (upgradable to a faster 68030), 1 meg of RAM and 2 RS-232 ports. Other VME cards provide the necessary analog and digital inputs and outputs and SCSI port. An ethernet board provides communications with the UNIX workstation based development environment. COMMUNICATIONS Communications with the vehicle is supported by a serial port for a monitor, a serial communications link through RF modems or acoustic modems and an etherlink. An RF video link has been designed and built for early testing and obstacle avoidance/location verification. NAVIGATION The baseline navigation sensor suite consists of a KVH fluxgate compass for heading, Shevits inclinometers for pitch and roll, Watson rate sensors for pitch, roll and yaw rate, Precision Instruments depth sensor and Mesotech altimeter. In a parallel navigation system development effort, HBOI has through a cooperative agreement, obtained a Kearfott ring laser gyro (RLG), and an EDO Doppler speed log. HBOI is currently writing the navigation software and building the dedicated navigation computer, consisting of a VMEbus CPU 68020 with an 8 channel asynchronous serial communication module, for the addition of these high performance sensors. Interfaces for GPS and USBL acoustics are also available. PAYLOAD For potential payloads, the VME backplane and VxWorks can support multiple processors and interface cards. Hence, payload specific processing tasks can be implemented on dedicated processor cards mounted on the VME back plane or mounted externally but communicate with the main computer system over ethernet or serial links. Payload capacity varies depending upon each mission; however, adequate payload bays have been provided both wet and dry, to accommodate most missions. The vehicle is also modular allowing for shorter, longer, or multiple sections to be added. HARDWARE IN-THE-LOOP SIMULATION HBOI currently has a high fidelity, hardware-in-the-loop simulation of the Ocean Voyager which runs on a Silcon Graphics Inc. (SGI) Indigo/Elan work station. Modifications of the existing simulation is performed when a new payload or capability has been added to the vehicle. Simulated runs are then conducted to verify performance and stability.