SEA-LOG A Sustainably Energized, Adaptive, Littoral Ocean Grid

We propose a distributed underwater sensor grid for covert and persistent monitoring and environmental characterization of ocean physical properties, ambient noise, and the seabed in littoral regions. Each node consists of a single-point, catenary moored sub-surface float that harvests wave energy, providing power for sensors, data processing, communication, and horizontal and vertical mobility, enabling the float to avoid hazards and accidental detection. This concept embodies several revolutionary advances: a silent inductive generator to convert sub-surface wave energy to electric power; vertical mobility using a simpler buoyancy engine than existing gliders and drifters; horizontal mobility using synthetic jet or ionic polymer actuators; and using noise from passing ships to characterize seafloor properties.