News This Raspberry Pi Boat Computer is for Sailors

[Admin]

This DIY Raspberry Pi computer project has everything you need for a day out on the water.

This Raspberry Pi Boat Computer is for Sailors : Read more

 

[robotboy321]

This Raspberry Pi Boat Computer is for Sailors

A boat computer for sailors? Are they sure it's not intended for those who travel by horse?

 

[derekullo]

A boat computer for sailors? Are they sure it's not intended for those who travel by horse?

Powering a Raspberry Pi with a boat ... Easy

Powering a Raspberry Pi with a horse ... Now we are talking

A horse is theoretically able to make enough power to power a Raspberry Pi.

https://www.britannica.com/science/horsepower
The electrical equivalent of one horsepower is 746 watts in the International System of Units

A just learned this today but a single horse can make more than 1 horsepower ... 15 peak horsepower to be exact
https://energyeducation.ca/encyclopedia/Horsepower
Let's use 4 horsepower which I imagine would be a comfortable stride

746 watts per horsepower * 4 horsepower = 2984 watts per horse

The Raspberry Pi uses 7.6 watts at full load
https://www.tomshardware.com/reviews/raspberry-pi-4-b,6193.html

7.6 watts / 2984 watts = 0.00254% of the horse's comfortable capacity

Even with horse to electricity conversion through some mechanism attached to one of the horse's legs, which would probably cut the horsepower by 1/4 if you only use1 leg, not being 100% efficient we only need much less than 1% of the horse's energy output.

 

[derekullo]

You could power a Raspberry Pi and a Wifi adapter to send an email from a horse.

Horse powered email FTW.

 

[Darkbreeze]

The "E" in that E-mail, must stand for Equestrian.

 

[bit_user]

I would not trust a Pi for anything mission-critical. Get a proper industrial or marine PC.

The one positive about this project would be if it's cheap enough that you could easily get two. However, there could be some batch failure that makes them both unreliable. However, I hear that mariners are wise to such issues, and often get backup systems that are an entirely different brand than their primary.

 

[GeoffreyMH]

I would not trust a Pi for anything mission-critical. Get a proper industrial or marine PC.

The one positive about this project would be if it's cheap enough that you could easily get two. However, there could be some batch failure that makes them both unreliable. However, I hear that mariners are wise to such issues, and often get backup systems that are an entirely different brand than their primary.

Having twice been struck by lightning (once mid-Atlantic, once at anchor in Belize) I notice that nature isn't picky about what brand or make of electronics equipment it destroys. Both times it destroyed both our Raymarine autopilots (yes, so much for backups!). Now I rely on my windvane (Monitor) self steering.

Monitor offer a relatively low-cost autopilot (£800) that drives their self steering for those times when you are motoring in no wind. Meanwhile, I have written my own autopilot that runs very nicely on a £17 Raspberry Pi 3A and uses a £20 12v stepper motor instead of a linear actuator. I certainly wouldn't bother with a "marine computer" - a Pi 4 in an Argon 1 case will do everything you want. And it is tiny enough to fit in your oven or a small cake tin when there is lightning about. Loads of open-source software on the web for chartplotting, autopilots, etc (eg Open CPN, pypilot and so on) and LibreOffice leaves Microsoft Office for dead.

 

[bit_user]

Thanks for the reply. It's great to hear from someone with actual experience, which I clearly lack.

Having twice been struck by lightning (once mid-Atlantic, once at anchor in Belize) I notice that nature isn't picky about what brand or make of electronics equipment it destroys. Both times it destroyed both our Raymarine autopilots (yes, so much for backups!). Now I rely on my windvane (Monitor) self steering.

I gather the point about having a backup of a different brand was in case there's a bug or internal defect in the device. As you point out, it's not going to protect you from lightning.

I certainly wouldn't bother with a "marine computer" - a Pi 4 in an Argon 1 case will do everything you want. And it is tiny enough to fit in your oven or a small cake tin when there is lightning about. Loads of open-source software on the web for chartplotting, autopilots, etc (eg Open CPN, pypilot and so on) and LibreOffice leaves Microsoft Office for dead.

My concern about using Pi hardware is that it was built primarily to hit a low price point, and not to prioritize robustness or reliability. The first thing you want to look for is ECC memory, but industrial boards will also use higher quality components, PCBs, etc.

In conclusion, I'll just say that if it were my ass on the line, I would go the industrial PC route and not rely on a Pi. Also, beware that flash drives and SSDs have data retention issues, if you leave them unplugged for too long. So, I would chose my storage wisely. Some filesystems, like BTRFS, even have a checksum. So, you can simply check it before launching, to verify that your data is 100% intact.

 

[GeoffreyMH]

Thanks for the reply. It's great to hear from someone with actual experience, which I clearly lack.


I gather the point about having a backup of a different brand was in case there's a bug or internal defect in the device. As you point out, it's not going to protect you from lightning.


My concern about using Pi hardware is that it was built primarily to hit a low price point, and not to prioritize robustness or reliability. The first thing you want to look for is ECC memory, but industrial boards will also use higher quality components, PCBs, etc.

In conclusion, I'll just say that if it were my ass on the line, I would go the industrial PC route and not rely on a Pi. Also, beware that flash drives and SSDs have data retention issues, if you leave them unplugged for too long. So, I would chose my storage wisely. Some filesystems, like BTRFS, even have a checksum. So, you can simply check it before launching, to verify that your data is 100% intact.

The Raspberry Pi was not built to hit a low price point but to educate peope to use computers and electronics-driven equipment. There is now a vast knowledge base on the Pi to support anyone who wants to learn.

Sure, your ass is really on the line when you use any kind of electronics on the boat. Lightning strike is far more common than people tell you - in Florida, for example, 20% of boats get hit a year. Especially vulnerable is the modern diesel engine with electronic not mechanical fuel injection, or the smart (microprocessor-cotrolled) relays that replace a 1-2-Both switch for battery charging.

And then there is the cost. The key sensors of an autopilot (gyroscope, accelerometer and magnetometer) are packaged in the Raspberry Pi Sense Hat for £30 from Amazon. It was tested in space flight. While the B&G "marine" Halcyon Gyro Stabilized Compass Pack costs $1,796. Think of it, the requirements to stabilise a £20 drone are far more rigorous than those to steer a relatively slow-moving sailboat.

Then there is the obsolesence, a huge factor for electronics-intensive power boats. Who is going to service and maintain ten year old systems, and at what cost? Hence the marine electronics engineers's quip: "if it ain't broke, change it out any way". A self-sufficient sailor in the world of electronics needs to be more than able to backup micro SD cards.

Of course such problems go far beyond boats to afflict our modern cars, bikes, etc. A good friend who is a long-distance motor-biker tells of an acquaintance whose fancy new BMW packed up in Kurdistan (fortunately the only one of the 'stans with a BMW dealer). So he put his bike on the back of a pickup and drove the 1400 miles to the nearby dealer... only to find once the diagnostic computer was plugged into his engine that it was an intermitent fault on a light bulb that had immobilised his bike. Swearing to be never caught this way again, he spent £7,000 on a laptop plus all the software to go with it to take on his next trip with him. Needless to say, three weeks into that trip the valuable laptop was stolen.

Live by the sword, and you die by the sword. True. But the Raspberry Pi is a wonderfully cheap and mind-sized little sword!

 

[bit_user]

The Raspberry Pi was not built to hit a low price point

Yes, it definitely was. The Pi's creator has previously stated that price was everything. They tried to pack in as many features and as much functionality as they could, and still have an entry price of $35. But, at the end of the day, that price was non-negotiable.

It was not built for reliability or robustness. The overheating problems are evidence of that. The Pi v3 could even be driven to malfunction, under stressful workloads.

but to educate peope to use computers and electronics-driven equipment.

Yeah, that's the motive. But that same motive drove them towards maintaining a low price point.

There is now a vast knowledge base on the Pi to support anyone who wants to learn.

Which I'm sure is going to be a great source of comfort, when you're stranded in rough seas, with a Pi that keeps crashing or won't boot.

Look, do whatever you want. I was just explaining my concerns, what I'd use, and why. The cost of an industrial PC is probably insignificant, by comparison with boat maintenance, operating, and storage costs.

And then there is the cost. The key sensors of an autopilot (gyroscope, accelerometer and magnetometer) are packaged in the Raspberry Pi Sense Hat for £30 from Amazon.

Is there no USB peripheral available with those sensors?

 

[mikanesh]

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Hi bit_user & Geoff,

i read with great interest this debate as a newbie wannabe sailor looking into setting up my own centralized nav system for our soon to be bought cat.
So thank you to you both.

This being said, with the lack of practical experience that i have i'm totally failing to understand you bit_user.

Do you really rely on electronics and proprietary systems for your safety ?

In my understanding this thing is for comfort, to make it easy for the wife & mate to help with navigation during a crossing while i'm sleeping.
it's easy& cheap to backup & it's possible to fix any failure anywhere whenever one component fails (save the topnotch radar antenna obv), you can vacuum bag spare SBC & cards backup, to store in foam coated metallic box. Again it's your own, it's cheap & easy : exactly the opposite of what you propose.

Me inexperienced sailor but software developer for my safety, when thinking about us getting caught by mistake in an unexpected storm i want for my family mechanical backup for autopilot, winds, atm pressure and i want handheld (above) marine grade vhf & gps that can last ages without recharge whatever happens.

Never ever i would consider putting the safety of my family in any PC, even marine grade (industrial grade is way far below, no industry are working in salty environment) and moreover when the software is proprietary.

As a software developer i will cut cost on all the comfort items especially if it helps making them my own & easily & cheaply maintainable or replaceable.
But never i will cut cost on the backup safety stuff (that i hope i will never need but that i believe we all need), whatever the fancy or not, cheap or expensive, nav system we install.

 

[bit_user]

This being said, with the lack of practical experience that i have i'm totally failing to understand you bit_user.

My point is simple: if there's a piece of equipment you depend on, then use one that's built with robustness as an objective. There's a whole world of different industrial and embedded computing products that are designed with features to improve reliability, longevity, and provide some level of fault-tolerance. That's what I'd use - not a Pi, which was built primarily to provide a low-cost platform for students and tinkerers.

Do you really rely on electronics and proprietary systems for your safety ?

I have no hands-on experience with these types of systems, if that's what you're asking.

And other than basically satisfying my Sailing merit badge requirements, I have no sailing experience.

In my understanding this thing is for comfort, to make it easy for the wife & mate to help with navigation during a crossing while i'm sleeping.
it's easy& cheap to backup & it's possible to fix any failure anywhere whenever one component fails (save the topnotch radar antenna obv), you can vacuum bag spare SBC & cards backup, to store in foam coated metallic box. Again it's your own, it's cheap & easy : exactly the opposite of what you propose.

Maybe I have a very distorted view of boating, but it doesn't seem to me like a basic, industrial PC would be very expensive, either. Maybe we're talking in the ballpark of $500 instead of $50. If that's a deal-breaker, then get two Pi's with two memory cards and you'll probably be fine.

Whatever you decide to do, I wish you the best. I have no stakes in this - just offering my opinion.
: )

 

[GeoffreyMH]

HI mikanesh and bit_user

IMHO there is an important practical issue about our increasing reliance on electronics not just in boats but also in modern cars – who is going to service it? If the electronics that delivers a large part of the car or boat’s functionality (and that represents a large part of its cost) is likely to become hopelessly obsolete in 10 years then so is the car or boat.

This is particularly important for a boat if you sail it to more exotic, less-developmed corners of the globe where you might not find the sophisticated electronics skills you need.

I have a friend with a large, expensive twenty-year-old Nordhavn motor yacht equiped with fancy electronics who faced huge interfacing problems (and cost) as laptop technology and Windows software evolved. This is one of the reasons those boats depreciate so fast.

I raised the issue with another acquaintance who fits sophisticated electronics on expensive ribs and he said he always advised the customers NOT to update their software: if it is all working don’t touch it!

The system is the boat + the owner. If you do get into trouble mid-ocean with complex highly-interfaced electronics then you will certainly wish you had followed the KISS principle (Keep It Simple Stupid!).

For example, watch the documentary Red Dot on the Ocean which tells the story of Matt Rutherford who was the first person to complete a solo, non-stop circumnavigation of the Americas via the Northwest passage and Cape Horn. By the end of the trip every system on his boat was broken, except one of his three GPS’s. He had kept it simple and was lucky!

So my advice to a long distance sailor is to have many, cheap, stand-alone SBC devices that you understand and can maintain yourself rather than elaborate electronics that very few people can service.