Electromagnetic Ship Docking System Debuts

Makarand writes "A system that uses electromagnets for docking ships is getting ready to be tested at a port in the Netherlands according to this article in the New Scientist. Magnetic docking systems were never used in the past as magnetic fields posed dangers to sensitive cargo like TVs and monitors. Researchers at the Delft University of Technology have developed electromagnets whose magnetic fields do not penetrate far into the ship for this special application. The magnets can be periodically switched off and on rapidly to allow ships to rise and fall with the tide."

Comments

BAD PUN ALERT

[Anonymous Coward]

Electromagnetic ship docking systems are very attractive.

Re:BAD PUN ALERT

[Anonvmous Coward]

"We can't let them replace dock workers just because they have magnetic personalities!"

Are you kidding? Most dock workers are bi-polar.

So what does the dockworkers' union think?

[MacAndrew]

Seriously, in the U.S. we just recently had a paralytic dockworkers' strike. I don't think they'd be amused by this labor-saving innovation. Not that I think people should be kicked out of jobs by robots.

Each of their mooring magnets generates a 1-tesla magnetic field. (from NS article)

WOW! That's strong. I used to work with a 1.5-T superconductor magnet, an MRI scanner, and it had a heck of a pull. Enough so that people have been injured or killed when a piece of metal got loose. It took three of us to pull off the base of an IV pole (no one inside at the time). Some of the research magnets are 4-T or more. But these are all superconductors, and act like permanent magnets. The resisitive magnets here must produce tons of heat while gobbling electricity. Surely "auto-dock" wouldn't be too hard to design., with mechanical restraints?

A solution looking for a problem

[NumberGod]

You've never going to save 40 minutes.

This is just a solution looking for a problem, and I'll predict that it'll never ever be used.

I live at a port in New Zealand (just outside Christchurch actually) and often watch the ships docking. My father used to tie them up. If I look to my left, I can see about a half-dozen ships out my window.

The majority of the 40 minutes that the article quotes, that it takes to berth the ship, is the tugs turning, and pushing the ship to the wharf. That's the thing with ships, they have a big propeller at the back, which pushes them forwards, and they can't move from side to side. They do have a rudder, but it's not designed for more than a few degrees of turning, you can't use it to dock. (I'll stay away from bow thrusters for now)

Basically the process goes like this...

A Pilot (who works for the port, and is an expert in the local navigation/conditions of the port) is taken to the ship on a small launch, and meets it several miles from the harbour.

The Pilot then commands the vessel, until it's tied up at the wharf. (s)he co-ordinates the ship, tugs, and wharf staff who, at the end of the operation drop the ropes over the bollards.

Securing the ship with the ropes takes about 5 minutes on a slow day, getting the ship alongside the wharf takes about 35 minutes. The thing with ropes is, that...

1) They're proven. They've been using them for thousands of years.
2) It's a standard system, used all over the world.
3) It's simple, never underestimate this.
4) it copes well with varing weather and tides.
5) You still need ropes to tie between the tugs and the ship.

Now, as I said before, you've going to save about 5 minutes per berthing? Your damage costs are going to far outweigh the costs of any savings.

And, what happens when the power goes out?

The ship floats away, probably onto rocks.
Backup Generators? Yeah sure, a diesel generator is going to hold a ship with 4-8000 shipping containers alongside a wharf, is bad weather, and an especially high tide, with no outages.

I'm sorry, but there's no way this would ever work.

Re:Residual magenitsm of the hull?

[cybermace5]

Ships routinely have degaussing coils run along the inside of the hull.

The earth's magnetic field tends to magnetize a ship over time. During the second world war, torpedoes and mines used magnetism as one method of detecting that a ship was near. The magnetism would also mess with the compasses, of course. Large ships, lacking degaussing coils, would routinely go back to port and dock in a way that used the earth's magnetic field to gradually cancel out the ship's magnetism.

I'm annoyed by a lot of these comments

[Fastolfe]

A lot of these uneducated comments in here are really bugging me. I see a lot of people saying this is a stupid idea, it'll be too expensive, it'll never work, etc. What is with all of the negativity?

First of all, this is an experiment. Experiments never usually make money in the short term.

Secondly, here's a quote from the article (which several posters need to actually read):

If it works, they say the system could save them around 5 million Euro a year in labour costs, and speed ships' average turnaround times by 40 minutes.

Could we please concede the possibility that someone has done a marginal amount of research into this and backed these figures up on some real numbers? Maybe it won't save them that much, or maybe the whole thing will end up costing too much. That's the point of an experiment, after all: to determine if something is going to work.

And for all of the couch port authorities inhabiting Slashdot, please remember that this is probably going to be done with the blessing (and financial support) of a large ocean port. I know that perhaps many of you think you know more about docking ships, managing large ocean-going vessels and the expenses associated with these activities than those in charge of these ports, but please take a deep breath, relax for a minute, and consider the possibility that maybe they're supporting this experiment for a reason, and that reason probably has less to do with a mad scientist trying to dupe someone into buying them a lot of expensive magnets and more to do with a convincing argument that this experiment could save them money in the long run.