Ocean-going robots that could revolutionize fishing, drilling, and science • Hacker News Board

Re: Ocean-going robots that could revolutionize fishing, drilling, and science

#91

Post by carapace » Tue, May 22, 2018, 4:55 AM UTC

Jedi72 wrote: post #85

carapace wrote: post #66

I'm so jelly! ("jealous") I've been (slowly and painfully) working my ways towards constructing a self-reproducing robo-boat swarm for a few years now, ever since learning about the Great Pacific Garbage Patch. My idea is to set up a simple artificial ecosystem of interacting bots that collect and recycle oceanic trash to create more of themselves. This permits exponential growth, making it realistic to attempt to ta…

You get an upvote for the sheer audacity of this project. Hope you make good progress, good luck.

Cheers!

It's been slow going, working mostly in my spare time, but I'm committed. I've got two boats now for hosting the initial "kernel", and some time this summer to double down. One benefit of taking so long is that neural networks et. al. have taken off in the meantime and that should solve a few problems that might otherwise have been hairy.

Re: Ocean-going robots that could revolutionize fishing, drilling, and science

#92

Post by namibj » Tue, May 22, 2018, 10:05 PM UTC

petre wrote: post #82

namibj wrote: post #64

Earlier quoted context omitted.

Apart from wind moving it to the side, it would not be a fundamental problem to fly a tethered blimp with a pair of single mode fiber and a thin aluminum wire that is driven in resonance [0] with the surface capacitance the blimp has, relative to earth, up to about 20-50 km. The breaking length of the fiber comes out at ~120 km, and you have to spare some tensile strength to hold the aluminum wire. This is not hard,…

Lightning + aluminium wire is a problem. I suspect an electrical current will form in the wire even w/o lightning because of static electricity. Also the wire is a hazard if it breaks and falls down. It will probably cut everything in its path.

Yes, probably. Maybe you'd have to fly it at a place where you don't need to worry about lightning. But that seems rather restricting. Though, for high-bandwidth applications, it might then be necessary to fly local power, and have the whole system sit over the cloud layer, at about 50km.

Regarding the damage from it when falling down, you have to remember that each fiber weighs 50g/km, and the wire is also below 1kg/km, even for rather low heights. This should not be a problem, considering the ease of breaking an optical fiber optic at any remotely sharp edge. A small bird (the size your cat can catch) could probably snap it if he hit's it with some force.

Re: Ocean-going robots that could revolutionize fishing, drilling, and science

#93

Post by scooble » Wed, May 23, 2018, 8:19 AM UTC

ganashaw wrote: post #90

scooble wrote: post #84

Earlier quoted context omitted.

How do your vessels comply with the international collision regulations? In particular, the requirement to 'at all times maintain a proper look-out by sight and hearing as well as by all available means appropriate in the prevailing circumstances and conditions'?

As it happens my full-time job is working on our COLREGS path planning and collision avoidance :) Our primary focus at the moment are the rules concerning standing on/giving way with respect to other vessels. Some of the other rules, such as the one you mention, aren't being handled at the moment. However, we do have active projects working on the vision side of things to help get us closer to full compliance.

Good to know. My primary concern, as a sailor, is a drone having no way of seeing me. Not all yachts have AIS, and radar can be notoriously unreliable in certain conditions. The drones in the article are only a touch smaller than my yacht, and quite possibly capable of sinking it in the event of a collision. And while it may be relatively straightforward to program stand on/give way behaviour, some of the other aspects of the the colregs, and good seamanship, such as responding to sound signals seem more intractable.

Re: Ocean-going robots that could revolutionize fishing, drilling, and science

#94

Post by [deleted] » Thu, May 24, 2018, 8:18 PM UTC

petre wrote: post #82

namibj wrote: post #64

Earlier quoted context omitted.

Apart from wind moving it to the side, it would not be a fundamental problem to fly a tethered blimp with a pair of single mode fiber and a thin aluminum wire that is driven in resonance [0] with the surface capacitance the blimp has, relative to earth, up to about 20-50 km. The breaking length of the fiber comes out at ~120 km, and you have to spare some tensile strength to hold the aluminum wire. This is not hard,…

Lightning + aluminium wire is a problem. I suspect an electrical current will form in the wire even w/o lightning because of static electricity. Also the wire is a hazard if it breaks and falls down. It will probably cut everything in its path.

[deleted]

Re: Ocean-going robots that could revolutionize fishing, drilling, and science

#95

Post by petre » Thu, May 24, 2018, 8:30 PM UTC

namibj wrote: post #92

petre wrote: post #82

Earlier quoted context omitted.

Lightning + aluminium wire is a problem. I suspect an electrical current will form in the wire even w/o lightning because of static electricity. Also the wire is a hazard if it breaks and falls down. It will probably cut everything in its path.

Yes, probably. Maybe you'd have to fly it at a place where you don't need to worry about lightning. But that seems rather restricting. Though, for high-bandwidth applications, it might then be necessary to fly local power, and have the whole system sit over the cloud layer, at about 50km. Regarding the damage from it when falling down, you have to remember that each fiber weighs 50g/km, and the wire is also below 1kg…

It will create a lightning discharge path regardless if you fly it over the cloud layer.

1 kg/km • 50 km • 9.8 m•s^-2 • 50 km = 24.5 MJ

10 MJ = kinetic energy of the armor-piercing round fired by the assault guns of the ISU-152 tank

I think that's just about enough energy to cut just about any living thing in half. Maybe it work if the cable was made of spider silk or Kevlar.