i've been reading about seafloor mining for years.

much of the proposed commercial interest in mining centers on the ocean floor collection of dispersed small spheres called manganese nodules.

these nodules are dense concentrated highly valuable ore, but dispersed over massive areas of ocean. how do you collect these most efficiently with the smallest expenditure of energy?

i propose a model where a 'mothership' sits on the ocean floor and runs and 'elevator' conveyor belt to the surface to pull up the aggregated collected nodules .

the issue here is , how do you collect all the nodules over dispersed areas? you need highly efficient drones that scour the sea floor, pick up the nodules and return them to the mother base. the drones need power refilled when they run out. instead of travelling a full mile or two straight up through the water column, they can refuel themesleves through a system at the mother base. the mother base elevator cable also acts as a transmission mechanism for a form of energy ( electricty or pressurized air or electromagnetic energy or hydrocarbon fuel ) ----which delivers the energy supply to the motherbase ( where it is stored in an energy storage device, and converted from one form of supplied energy to the form of stored energy ).

this model provides for a network of seafloor scouring drone nodule scavengers that do not have to return to the surface every time they are 'full' by hitting their weight limit of modules, or every time they run out of energy.

the difficulty of scouring the coean floor requires extensive AUTONOMOUS navigation and planning for energy supply management. this supply management changes due to many ambient conditions and travelling repeatedly up and down the water column to some series of energy providing boat or surface stations is not only energy intensive but requires floating platforms all over the place that all have to deal with waves and periodically stormy conditions.

the elevator station that also serves as an energy conduit will obviously connect to a central surface station , but that station can be run efficient like a floating oil platform that perhaps has massive fuel supplies or ---perhaps even a set of wind power plants that float on the water surface and provide an energy source that is transmitted through the elevator cable.
-- teslaberry, Feb 03 2014

So what's the mothership for? why don't the drones recharge directly from the elevator cable/conveyor belt?
-- erenjay, Feb 03 2014


The mothership is for the Evil Criminal Mastermind to run his Evil Criminal Empire from, via the fleet of innocent looking shrimp fishing boats which appear to fish in the area but in reality transport vast quantities of manganese nodules to the underworld manganese market. Whatever you do, don't touch that red button...
-- Harry Mudd, Feb 03 2014


mothership moors the elevator to the seabed, and docks drones while they charge, fixes broken drones , and relays infomratoin up and down the water column .

also, very importantly, if you have a surface power providing system, for example a giant ocean windmill it will not only be powering the elevator, but will send electricity down to the mother ship, where the electricity can be stored in whatever form is most stable, and then used by the drones as needed.

the mother ship will also be processing the nodules in whatever way makes them most concentrated and easiest for transport up a mile or more of water.

when you lifting that kind of weight through the water column, best to pakcage and process your product as efficiently as possible. that takes energy and equipment---all aboard the mothers ship. prehaps it's easiest if its a nuclear powered submarine and the drones all fit in and are depoloyed through the torpedo tubes?
-- teslaberry, Feb 03 2014


Why not just have nuclear powered drones that hoard all the manganese marbles into one place for collection?
-- erenjay, Feb 03 2014


Hey, [Harry Mudd] is back! Greeting!
-- MaxwellBuchanan, Feb 03 2014


Please double check the difficulty of building a 4- 6km conveyor belt/elevator, in order to reach the high concentration area on the abyssal plain.

It probably makes more sense to deploy each independent craft with a series of inflatable pouches and a tank of compressed air. The pouch is filled with sufficient mass, and then inflated from the tank. The air movement while inflating can also run a turbine to provide additional power to the craft. The pouch floats to the surface, where a GPS equipped homing beacon is activated, so it can be picked up by a surface ship.

Periodically, the surface ship repacks a new cartridge of pouches and an air tank, and drops them to the bottom, where the autonomous unit picks it up and continues on it's way.
-- MechE, Feb 04 2014


Alternatively, the last pouch is simply oversized, and the unit resurfaces itself with it, whereupon it is recovered, reloaded, and resunk.
-- MechE, Feb 04 2014


//Alternatively, the last pouch is simply oversized, and the unit resurfaces itself with it, whereupon it is recovered, reloaded, and resunk.//

[MechE] I like your first idea better. It seems like it could take a couple hours to reach the surface using just boyancy and another couple to sink back to the bottom, so just drop the resupply a couple hours before it is needed so the drone can keep working on the bottom continuously. Of course the last package can contain the air tank and bag dispenser to be refilled. And don't forget to send down more fuel as well.

Does sonar work well for communication at that depth? You'll need sonar beacons on the resupply package for the drones to find them as well. Sonar will be low bandwidth and delayed, but should allow for tracking the drone location and commanding it to go in the right general direction. High res photos or other data collected can be sent to the surface in flash memory in the GPS homing beacon modules.

Hmm, this doesn't sound that hard except maybe the actual semi-autonomous mineral collection part. What's the method for finding those?
-- scad mientist, Feb 04 2014


The latter is a simpler rover design, the former is more productive.

One of the major problems is with international regulation, not the actual technology.
-- MechE, Feb 04 2014


Can the drones go wakkawakkawakka as they eat up the nodules?
-- bungston, Feb 04 2014


mech E i like your idea, but i think the surface vessel that is the mother surface ship should not go around transporting these little devices separately without an elevator.

the mother ship should deploy the elevator underneath it which delivers the crab style drones that scour an radial area completely over time --- picking up all nodules from the full area circle around the center where the elevator it, and once the area is scoured, the elevator hauls the crab drones up to the top to the mothership. and the elevator is hauled up as well. the mother ship moves another 10 miles and then sets up .

repairs of the drones can be done on hte surface mothership. crabs that are broken so badly they cannot walk along the seaflor to return to the elevator base station------must be towed by healthy fucntioning crabs to the elevator. so the crabs have built in rescure cability ---which might be possible using echo location sonar units embedded at the base elevator bottom anchor----allowing it to see where the crabs are. i don't think it would be easy for the crabs to send information wirelessly at that depth to the elevator base station though.
-- teslaberry, Mar 06 2014


mech E i like your idea, but i think the surface vessel that is the mother surface ship should not go around transporting these little devices separately without an elevator.

the mother ship should deploy the elevator underneath it which delivers the crab style drones that scour an radial area completely over time --- picking up all nodules from the full area circle around the center where the elevator it, and once the area is scoured, the elevator hauls the crab drones up to the top to the mothership. and the elevator is hauled up as well. the mother ship moves another 10 miles and then sets up .

repairs of the drones can be done on hte surface mothership. crabs that are broken so badly they cannot walk along the seaflor to return to the elevator base station------must be towed by healthy fucntioning crabs to the elevator. so the crabs have built in rescure cability ---which might be possible using echo location sonar units embedded at the base elevator bottom anchor----allowing it to see where the crabs are. i don't think it would be easy for the crabs to send information wirelessly at that depth to the elevator base station though.
-- teslaberry, Mar 06 2014


mech E i like your idea, but i think the surface vessel that is the mother surface ship should not go around transporting these little devices separately without an elevator.

the mother ship should deploy the elevator underneath it which delivers the crab style drones that scour an radial area completely over time --- picking up all nodules from the full area circle around the center where the elevator it, and once the area is scoured, the elevator hauls the crab drones up to the top to the mothership. and the elevator is hauled up as well. the mother ship moves another 10 miles and then sets up .

repairs of the drones can be done on hte surface mothership. crabs that are broken so badly they cannot walk along the seaflor to return to the elevator base station------must be towed by healthy fucntioning crabs to the elevator. so the crabs have built in rescure cability ---which might be possible using echo location sonar units embedded at the base elevator bottom anchor----allowing it to see where the crabs are. i don't think it would be easy for the crabs to send information wirelessly at that depth to the elevator base station though.
-- teslaberry, Mar 06 2014



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