Marine Instrumentation Class HOVs, ROVs and AUVs Marine Instrumentation Class

HOV Human Occupied Vehicle Alvin Pisces IV and V Johnson Sea Link

Benfits/Limitations HOVs You are right there to see what is going on Limited by battery and air supply Quiet large and complicated to operate Usually have a dedicated support ship

UUV Unmanned Underwater Vehicle AUVs ROVs

ROVs Remotely Operated Vehicle Connected to ship with a cable Cable called either Tether Umbilical cable Fiber-optic cable with power and strength members Unlimited capabilities Wide Varity of sizes Micro (less then 3kg) Trenching more than 200hp Two mode of operation Free Swimming Garaged Large component in the Oil and Gas industry Pipeline inspection/repair Cable inspection Etc.

ROVs Scientific research Can perform tasks instrumentation is not capable of Push cores Organism collection Instrument retrieval Exact location sample collection Cheaper than a HOV

Benefits/Limitations ROV Complete control over operations For deepwater takes place of diver Can perform challenging tasks over long periods of time Continuously if needed Limitations lifting capability Requires skilled operator

AUV Autonomous Underwater Vehicle Various of sizes One-Man portable to couple of tons Powered by propeller Depth Range 0-6000m Dependent on Model

Eagle Ray AUV - NIUST

Benefits/Limitations Battery life Hours Large payload capabilities Capable of taking instrumentation with high power requirements Limits duration Most require surface support vessel

Gliders Glider through the water using only buoyancy as propulsion No external moving parts Travel Through water in Saw-tooth pattern Depth Range 0-1200m Dependent on model Multiple types Spray SeaGlider Webb Glider Wave Glider ANT Wave Glider

Underwater Glider Operation No external moving parts needed to control glider, control managed through changes in position of an internal mass This slide illustrates the cyclic saw-tooth flight profile that is achieved by pumping water ballast in and out of the vehicle. This video clip also illustrates this flight profile. One thing that is immediately apparent from the video is how slow the glider really moves. This can work against you in the presence of strong ocean currents; but it also permits one to operate acoustic arrays in the laminar flow regime with very low self noise. Energy only needed at top and bottom of each ‘yo’ to change buoyancy Wings provide forward motion during sinking and floating Slide Taken from ANT Littoral glider presentation 12

Teledyne Webb Research

Benefits/limitations Long deployments Months “real-time” data during deployment Limited payload Most are small easy to recover Communication fees are high

Power Wave Power Batteries Thermal Solar Alkaline, lithium…. Teledyne Webb Glider Use Ocean temperature change to alter the state of a wax, creating power Solar Wave Glider Power Concept

Limitations for all types Density Limited be displacement motor Currents

Challenges Positioning underwater AUV/ROV/HOV Gliders USBL Tracked by surface ship Doppler Velocity Log (DVL) Bottom Tracking Gliders Dead Reckoning Internal Navigation System (INS) Acquires new position every time it surfaces to calculated Currents

Communications ROV- Cable AUV Gliders Freewave (Radio comms) Surface Iridium (Satellite Comms) Acoustic Subsurface Gliders Freewave Iridium