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Computers That Thrive in Salty, Humid Environments?
To start us out, frostman asks: "A friend of mine is living on a sailboat, and would like to set up a nifty computer system. It doesn't need to be too powerful, but it should be small, rugged, fairly quiet, and cheap. He has a standard PII/400 mid-tower system he can gut for parts (400Mhz would probably be enough). He wants to do normal internet stuff, watch DVD's, listen to MP3's (with good speakers)... and he needs it to run on 12 volts when he's sailing. Any suggestions from the hardware gurus on Slashdot?"
websensei continues with this query: "I am about to become a full-time live-aboard on my sailboat. I'm in the process of selling all my machines and plan to spend about $2000 on a new laptop for the boat. I'll use it for work and play (movies, gaming, TV via USB TV tuner?) etc. Please share any advice/experiences relating to computing on boats or other harsh/damp environs."
And last, but not least, Alioth asks about fishes, not boats: "How about computers in fish factories? Not only do we have to contend with the room being jetwashed, but the atmosphere is very salty. I've been looking at stainless steel enclosures - what's their salt water resistance like, not just the stainless parts, but the parts that fasten the stainless parts together, not to mention being able to keep the computer cool as well (meaning it's got to vent somewhere)?"
In the factory, I'd look for something along these lines: http://www.industrial-computer-enclosure.co.uk/wat erproof_computer/waterproof_computer.htm
-- Mark Lyon http://www.marklyon.org
Kontron Mobile Computing. Manufacturers of rugged portable systems. www.kontron.com seems to be the overall companies homepage. Follow the KMC link. Their Revolution, an upcoming product, looks especially nice. Their 8000 series is designed for crazy environments.
My friend lived on his boat for 2 years and used a Dell Laptop with no salt-water related problems. He treated it like he stole it too, not being very careful or anything.
M@
Krispy Cream is people
There are tons of regular computers onboard sea vessels, the way they get around problems is to make the environment where the computers are NOT like a boat. Air conditioning, for managing humidity and temperature goes a long way to keeping electronics happy. If you want something that can get salt water splashed on it, you're talking something different.
Plastic is an obvious answer. It's resistant to water, salt, heat, etc.. Underwater camera housings are made out of plastic and work very well. For cooling, you can do a heatpipe arrangement with aluminum heatsinks on the inside and out.
The USGS has built entire PC's that are made to reside underwater for days logging data - they put them in watertight aluminum boxes and bind the heatsinks to the sides. Works great.
Check out TNAC if you need computers which are resistant to harsh environmental situations. The computers are built into the displays for a single, tough unit, are available in pretty decent speeds (PII & PIII), and have good onboard components (USB, 10/100 ethernet, etc.) They also only use 5W in standby, which is good for houseboats, etc.
P.S. No, I don't work for them.
I used an older Sony Viao laptop (I think it is like a Pentium 150 or 200), and threw a bit more RAM in it. I then went out and picked up a universal 12V adapter, which can not only power the laptop but will charge cellphones and all sorts of things.
If the laptop is cheap enough, having it die doesn't matter as much.
The only other tip I would offer is to try to avoid a touchpad, as the one on my Viao really doesn't like wet hands. I would go for one of those nipple things or maybe a trackball (do they still even ship with those anymore?)
There is some real nice PC navigation software, like Visual Navigation Suite, which hasn't crashed on me once and supports just about all the electronic chart formats out there right now.
You might want to check out rec.boats.electronics, as they have a bunch of useful information there as well.
Twostep
There are 10 different types of people in this world... those who understand binary, and those who don't.
Ripped from the specs:
"The GoBook MAX exceeds military specs for drop, water resistance, dust and vibration. The GoBook MAX thrives in the most severe environments imaginable. Freezing cold. Searing heat. Pouring rain. Intrinsically safe,(Class 1, Division 2, Group D) the GoBook MAX enables operators to safely work in HazMat environments; on flightlines, near hazardous chemicals or explosive materials. With Itronix' innovative CRMA(TM) wireless communications, radios can be swapped or upgraded within each unit. Backed by a limited lifetime warranty and comprehensive services package, the Itronix GoBook MAX sets a new standard for ultra-rugged, wireless computing."
Specs
Website
MaximumPC review
"TK-421, why aren't you at your post?"
Just being around salt water will cause excessive corrosion of exposed metal parts. I can remember a situation where the metal contacts between the daughterboards and backplane of a system were getting corroded and causing problems, and that was inside an enclosure.
Putting a PC inside of a completely sealed enclosure is not always a good thing because you need to cool it down, and this is usually done with fans, so unless you also want to install an air conditioner in the side of the enclosure, you might want to find a ruggedized PC.
There are some very sturdy ruggedized laptops out there which can apparently be dunked in the ocean, pulled out and keep going, but I think they might be cost prohibitive for you.
Recently at a trade show I saw some industrial PCs that you could literally hose down with a garden hose and they would keep running. However, you're probably looking at $5000 even for a base model of one of those. Just look up "industrial PC" on the internet if you're interested.
Perhaps your best bet is to search the internet for oceanographic research groups. These guys go out to sea with tonnes of electronic equipment for months/years at a time, and they seem to make out alright, probably on restrictive budgets. If you write a nice email to one of these people, they might be kind enough to offer you some real advice.
"I have never let my schooling interfere with my education." - Mark Twain
For example, there is a special RF emissions curve that you need to meet to be sure that you are not preventing your radios from hearing weak emergency calls. Also, power on ships is VERY problematic. Just what does "Ground" really mean on a ship? I saw 100 V potiental between Ground and Neutral on a US carrier. And you do not want to know what all of this does to RF shielding. While RF may be no big deal on shore, remember that you are using radar and all kinds of radio communications on board ship. One thing that kept surprising me was the levels of ESD on board. I assumed that the moist marine air and metal decks would kill any ESD, but I had to keephaving to over building ESD protection for our keyboard. The other kicker is that the ship has to be kept in electrical "balance" with the sea to keep the metal from coroding into the sea.
Another area of the spec that surprised us was vibration. The shake and vibe spec on IEC-945 is a bear to pass. We started with a standard industrial chassis resting on shock mounts in the base of our console. We put that on the shake table and it killed the PC dead. The vibration was so bad that it caused the fingers of the backplane connectors to cut through the daughter cards. I was seeing fiber glass poking through the gold fingers when I did a post mortum. As an EE I learned that intuative answers are not good enough for the "real-world" mechanicals and that you need to hire a shake and vibe ME to make it work. (As an asside I had a friend who had his 36 ft sail boat out in the ocean and hit a standing wave that rattled his boat so hard that it shattered his ceraic head. Gotta wonder what the impulse was on that hit)
There are also a host of other issues such as fungus that will grow inside warm enclosures and choke-off ventalation
You should be able to buy IEC 945 PCs if that's all you need (HP used to sell some). If you really need this hardware to survive buy real IEC 945 hardware if you can live without it (and I do mean live) then go buy some laptop and assume that it is disposable. You'll pay through the nose for this level of hardware, but it will be cheaper and much quicker than doing it yourself.
-s
In the auto industry we have a thing called a conformal coating. Once the component is assembled its dipped in a kind of goo. That coats its components and protects it. However, this renders the components non-changeable so all-in-one boards would fair much better. Plus I doubt these heat factories would like the coating that much either.
Also, google produces many results for "rugged(ized) computers" if you want to buy something particularly hardcore straight out of the box.
Barnacles
If you've never seen them, they're little critters that attach to everything, and grow, with very hard shells. All oceangoing ships have to be dry-docked every so often and have the barnacles (and other ocean critters) sandblasted, ground, dissolved, and photo-flashed off the hull. This is done to improve speed and fuel efficiency. If you get into the 3rd world, sometimes you can see boats that have a good foot of ocean critter crust attached to the hull.
Now imagine your PC water cooling hose becoming slowly clogged with critters. Plus you'd likely suction up something else, like kelp or seaweed.
If you just want to embed a metal plate in the hull, and weld a heat transfer unit to it on the inside of the boat, that'd work nicely. A closed-loop water cooler. That'd allow you to use other fluids, like adding some glycol, so that the thing didn't freeze up, expand, and break, if you didn't use the computer some icy day.
The current (july/august 2002) issue of Latitudes & Attitudes magazine has an in-depth article (sorry, no direct link) on selecting desktop computers for use on boats. The author makes a pretty good case for using a desktop system instead of a laptop (easier to upgrade, easier to service, less expensive, etc.). His choice was a Shuttle SV 25 with a big LCD monitor for watching DVDs and a good sound card for listening to MP3s. This guy is cruising (as opposed to living at a dock) so power consumption and the availability of parts and service overseas were factors in his choices. The article is very detailed with lots of suggestions and well worth checking out if you are planing on installing a computer on a boat.
This issue also contains the news that you no longer need to go to all the way Caracas for LASIK surgery in Venezuela. I know I feel better knowing that!
I don't know about just any type of computer. You'd think that things are fairly resistant to salt water and what not, but then once you're out over the salt water for a while it gets ugly. I've worked on a drilling platform in the Gulf of Mexico and things just don't stay intact for very long. Up on the rig floor it didn't take very much time at all to ruin a good set of tools just from the salt water eating them up. Keep in mind that the floor of the platform is roughly 75-100 feet off of the water and this guy will be on the water. You'd need a bit more than just a good case that keeps water out and doesn't rust to give the computer a life of more than 1 month.
In any case, the stupid box has an internal heater -- Like anybody out there is going to need a heater for a P3. A couple of P4s can make a pretty good (but damned expensive) space heater!
More seriously, though.. these boxes are made for food processing (inc. freezer buildings) environments -- although there aren't many computer components that would mind being kept at -35c (disk drives come to mind as possible exceptions).
For a marine envirnemt, Possibly more valuable would be a closed-loop cooling system (like is often used by over-clockers.
Off the top of my head, you might try and hunt down a marine refrigerator.. Drill holes for the cables, then grout around them with silicon.
An external (scsi?) CD/DVD drive in it's own enclosure (smaller, easer to get to , not as likely to need cooling).
An LCD display is probably the best idea (smaller, cooler, less power).
As for power, you can use 24/12V->110V power inverters by people like StatPower (or whoever bought them). They range from 50W units that are good for laptops to gargantuan (KiloWatt range) monsters. A 250W unit is about the size of a 5" drive, but gets reasonably hot by itself.
Companies do make units specifically for marine operations.
That having been said, though... You may want to look for power supplies specifically for marine operations.. You're already starting with 12 or 24VDC. No real need to punch up to 110AC and then back down again.. All you really need are some medium-amperage voltage regulators (especially if you're starting at 24V). A two-stage regulator (24V->16V, 16V->12/5V) should give you the cleanest power you could ask for.and FAR simpler too. You could probably arrange to have the PS cooled by a sea-water sluice. (less heat to worry about inside the CPU enclosure). There are probably all sorts of people capable of building on for you (if absolutely necessary).
Gotta run now.. off to the beach :-)
Free Software: Like love, it grows best when given away.
A sail boat is quite a different environment from a power-driven ship. Jack Ganssle is an engineer and programmer with a serious sailing hobby, and he tells all sorts of stories of saiboat autopilots failing due to saltwater corrosion. I remember but cannot fine one article concerning long a single-handed race, where he had several spare autopilots and all of them failed. Since he was alone, the autopilot was critical. He kept repairing them, but his big question was, how would anyone who wasn't an electronic engineer or tech cope?
And these things are built for saltwater, unlike off-the-shelf computers. OTOH, the autopilot would be on deck next to the tiller, so exposed to saltwater spray pretty much 24x7. The cabin would be a little more protected - there might be condensation dripping from the ceiling, but it shouldn't be salty... Still, if it's mission critical (like how you get your weather reports), it's going to be hard keeping that computer going.