James Patten

Ocean-science mission needs: real-time AUV data for command, control, and model inputs [West Florida Shelf]

Predictive models for tides, hydrodynamics, and bio-optical properties affecting the visibility and buoyancy of coastal waters are needed to evaluate the safety of personnel and equipment engaged in maritime operations under potentially hazardous conditions. Predicted currents can be markedly different for two-layer systems affected by terrestrial runoff than for well-mixed conditions because the layering decouples the surface and bottom Ekman layers and rectifies the current response to oscillatory upwelling- and downwelling-favorable winds. Standard ocean models (e.g. Princeton Ocean Model) require initial and boundary data on the physical and optical properties of the multilayered water column to provide accurate simulations of heat budgets and circulation. Two observational systems are designed to measure vertically structured conditions on the West Florida Shelf (WFS): a tethered buoy network and an autonomous underwater vehicle (AUV). The AUV is described with a focus on the observational systems that challenge or limit the communications command and control network for various types of measurement programs. These include vertical oscillatory missions on shelf transects to observe the optical and hydrographic properties of the water column, and bottom-following missions for measuring the bottom albedo. Models of light propagation, absorption, and conversion to heat as well as determination of the buoyancy terms for physical models require these measurements.

Sensor development: progress towards systems for AUVs/UUVs MTS Oceans 2000

The oceanographic community is seeing new and substantial advances in the development of underwater vehicles. The future is near when we will witness networked fleets that will acquire synoptic data over wide areas. The potential of multiple, concurrent AUV/UUV deployments promises the ocean research community with increased data accuracy, the elimination of spatial and temporal aliasing, and more efficient and cost-effective means of data dissemination. To complement these advances in AUV/UUV technology, we will need continued development of new and more sophisticated sensor systems, to expand our understanding of the oceans processes. The University of South Floridas Center for Ocean Technology specializes in developing sensor systems to meet the ever-increasing need of oceanographers to collect high-resolution data relating to the chemical, biological and physical processes of the ocean. This paper presents up-to-date information about three of those instruments.

Design and initial results of high-resolution Shadowed Image Particle Profiling and Evaluation Recorder

Previous oceanographic imaging systems have relied on analog video or film recording methods to capture images of microscopic marine particles. Video system resolution is limited by the two-dimensional detector array used. High-resolution images are attainable, but typically with reduced imaging area. Recording to analog videotape has the added problem of introducing noise into the data. Unless the frame rate or instrument tow speed can be varied, particles are either missed or repetitively imaged, thereby making particle density calculations difficult or inaccurate. These methods also have the disadvantage of requiring time-consuming postprocessing of the data before the images can be analyzed on a computer. We have developed an imaging system based on high-speed digital line scan cameras to address the above shortcomings. The system is built around the 96 mm/spl times/96mm sampling tube of the University of South Floridas High Resolution Sampler (HRS) towed.