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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
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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
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 partsneeded to control glider,control managed throughchanges in position of aninternal mass 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
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 • Alkaline, lithium…. • Thermal • 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 • 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 • Freewave (Radio comms) • Surface • Iridium (Satellite Comms) • Surface • Acoustic • Subsurface • Gliders • Freewave • Surface • Iridium • Surface