SignalK Integrated modular system for boat automation.

Hello Guys,

I recently posted about my sailboat design project here: My custom design 62FT DS homeboat https://www.boatdesign.net/threads/my-custom-design-62ft-ds-homeboat.70120/

I also would like to talk about the electrical system and what I have been developing from scratch for my boat, which, as I also intend to sell, will help me pay for the boat construction.

I have extensive experience designing electrical systems, and I have been astounded by the poor standards for boat electrical systems.

First of all, how come not every box and device in a boat is not waterproof? The automotive industry has already solved this problem for decades, and cars are not even designed to live in salty waters!

Second, having an electrical room with all the switches is convenient; however, it creates a wire mess around the boat and adds unnecessary wiring.
I will use the automotive industry as an example again; distributed systems have a power bus and a communication bus to control modules, and those modules then distribute individual wiring to that section of the car.

Third, there is insufficient ground protection; all the boat systems I see around have very little ground protection and lightning arrestors.

And fourth: NMEA2000 is a big proprietary mess, CAN bus works great until it does not; a short or open bus can take down your entire network.

Those are my main complaints.

Based on those frustrations, I am designing the system for my boat from the ground up:

The highlights:

• Open Souce/Open Hardware devices, I want any boater to have the ability, with proper documentation, to fix their stuff in the middle of the ocean without communication.
• Modular system: Each room/ system can have its own control box which is independent from each other.
• Building blocks: Each control box can be customised with reusable building blocks, very easy to replace and affordable to have spares.
• SignalK Integration: No proprietary communication protocols anymore.
• Ethernet with PoE: Each control box has its own Ethernet cable, so if a cable fails, it does not take down the whole system. The power for the box is supplied via PoE, allowing you to have a UPS in the network rack that powers all the devices. The main power bus can go down, but you keep all the control boxes reading status all the time.
• Designed to fit IP67 waterproof boxes.
• Each control box can be independently controlled, even if your signalK server goes down you can still access via your browser the boxes and change settings, turn things on and off.

Let me show some pictures:

IP67 Box with the control box modules installed.



Waterproof box with the baseboard installed. The baseboard provides Ethernet communication and talks with the modules, the building blocks that provide the functionality. Each baseboard offers 8 slots for any combination of expansion modules.




A baseboard with different expansion modules fitted:




First boat boot with power:


There will be different expansion modules types, this one is a Relay Module, with current monitoring providing up to 15A 250VAC of capacity.



Here I have the general input modules:

They are 50V input tolerant for any 3V to 50 V sensor , The input and output general IO have 4 IO each.



A collection of different types of expansion modules, they will use Wago connectors for their reliability and ease to use:



I will post more later when I finish the tests and software.

Would you like to have this in your boat?

Cheers,
Vinicius

 

One of the drivers for this sort of system is the ability to multiplex some demand so as to maximize the utility of onboard solar and wind generation and minimize battery bank throughput. It can also manage generator autostart and generator loads. It may also have a significant effect on the weight and size of the onboard power distribution system. Refrigeration, water makers, water heater, and laundry can be controlled based on available power supply, time of day, etc. Simple stuff like automatically turning those things off while running the anchor windlass can result in significant weight and cost savings from the get go.

The biggest problem is probably the fact that most boats don't have a place to put wiring in the walls. You can run wires in the bilge or along the sheer behind a trim board, but that's about it. So there isn't a way to route wires to and from a box to different points in a cabin. This takes some of the shine off of the modular concept - it isn't really expandable or customizable in the way we usually think about these systems; and it isn't clear if we end up with any additional design freedom as far as locating equipment is concerned.

 

@Vinicius I like what you write, although I don't understand much of it. Automotive is not something that is always worth taking an example from.Saltwater is nasty place for electricity.For the beginning I need silicone cables, simple gold-plated easy to use DC connectors , waterproof rated by meters of immersion.

 

Lee: Completely agree. I looked at large numbers of youtube videos to see what was done on boats. Mosts of them scared the crapolla out of me. I live in a maritime town with freshwater and saltwater boats nearby. We oversea the Southern Ocean so our house gets a nightly dose of salt laden mist. I see how quickly that salty mist eats copper and connectors. I look at how boats around these parts are wired. It runs from obscenely bad to dangerous. House solid wire in screw terminal blocks. So yes in my little sailing boat I have joints sealed away in IP67 box's. Where I cannot I have sealed the joint with hot melt glue (please dont jump - it does keep the nasties away). I am not good enough to rest easy with control by wire on my boat so point to point is used but there is not much of it. I will add some network for avionics but never control.

 

Hi there, Automotive engineering is about as good as it gets for what we can afford. Trains and planes get very expensive stuff but use automotive grade parts. Think about how a car is built - everything is thought about and optimised for reliability, low cost and ease of manufacturing. Safety related stuff gets special attention but always price and 100% reliability get #1 spots. My 26 year old Nissan Patrol is running well and has never had an electrical "problem". Boats dont have the volume but we can adopt some automotive principals but always put our commercial connections inside water proof cases - they done cost much.

 

That is not correct. A submerged car will get all the electrics wet and ruined.

Cars don't need to have wires going for 150 feet or more.

Completely wrong. Aerospace has very different, and more stringent, regulations and standards than automotive.

 

GU ? I had GQ. I didn't notice that there was any electrics there.

 

First: Because waterproofing everything is not really required, it's really hard to do well, and even if you spend the money some systems are still reliant on proper operation. Let's take your waterproof box for example. At first look it's great, at a second look it's an amalgamation of potential problems. First it's plastic, and plastic is vapour permeable. You seal it up in nice dry atmosphere and water will migrate in do to osmotic pressure. Then it will condense and water droplets will form on your circuit board connections. That will also happen if you seal in moist air. If you use silica gel to dry the air inside, we are back to the first problem, wich you can only avoid by using a metal box with factory installed penetrations. Some devices also need heat removal, so metal is the only option.
You can do a perfect military grade factory install and after the first time someone opens the door it will still rely on some dude doing the right thing when he closes it.
So the common solution is to pot everything that has to be truly waterproof (like underwater lights) in resin, spray everything else with a protective film (there are several products) and install in a ventilated space.

Second: Distributed power systems on yachts are nothing new. Google "yacht digital switching" and you will find that Raymarine, Garmin, and a host of smaller firms sell it. If you buy a new yacht over 50ft it's probably there or available as an option.

Third: If you manage to invent a functioning lightning protection for plastic yachts your only thoughts about money will be how to spend it. Ground isn't a problem needing solving, just follow the standards.

Fourth: Unless you convince the instrument manufacturers to abandon NMEA2000 you will have to deal with it however you decide to run your network. Like it or not, that's reality for now. Users want to control the lights from their plotters, not only from their phones.