Collating and Displaying NMEA2000/Seatalk Data on Laptop or Tablet

Slowboat35

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I have a nice Raymarine based network with the usual (i50) speed/depth/wind, radar, AIS and chartplotter but of course the instrument displays are all in the cockpit. Most data is available at the chart table but is seems to me the best solution would be to display all the data on one screen at once, perhaps a tablet or laptop, or even a RaspberyPi and screen.
Of particular irritation is the seeming inability of the Raymarine gear to display boat speed and SOG simultaneously.

Is there a practical and inexpensive way of replicating the instrument displays on a remote screen? I'm not talking about Raymarine's misnamed Raycontrol (because it doesn't control anything) or the other bluetooth app that replicates the chartplotter down below because that too can't display all the data at once, and in any case the numbers ar so tiny they're hard for tired eyes to see.

I notice that some of the AIS transponders now have a USB iterface - will that carry the data I need? Would a special programme be needed to display it?

Electroinic whizzz-kids, go easy, I'm not a techncal computer person at all!
 
I know how I’d go about making something like this on a modern Arduino, but that’s a bit beyond “not a technical computer person” - I assume you’re looking for something off the shelf.

Maretron make software which “trawler” (big slow mobo) people often use in their wheelhouses, to show all the data from an extensive N2k system. N2kView is the name, but I don’t think it’s cheap.

For that matter, Maretron also make N2k display hardware - not sure if one of their offerings meets your needs?

Pete
 
A raspberry pi running openplotter can do that, with a canbus/usb adaptor to get at the n2k data. Then view it all on a monitor or any laptop/mobile phone/ tablet. Also record it all to a database and view the graphs. Easy to install & not much different to a mobile phone to configure. The Pi will run without a monitor, set it up with a tablet or laptop pver wifi then the data gets shown as a web page.
 
I know how I’d go about making something like this on a modern Arduino, but that’s a bit beyond “not a technical computer person” - I assume you’re looking for something off the shelf.

Maretron make software which “trawler” (big slow mobo) people often use in their wheelhouses, to show all the data from an extensive N2k system. N2kView is the name, but I don’t think it’s cheap.

For that matter, Maretron also make N2k display hardware - not sure if one of their offerings meets your needs?

Pete
No! Deffo not off the shelf. I can't afford that sort of thing. I'm thinking of buildng components at raspberry pi sort of level - but programming is beyond me.
 
Angus, sounds wonderful and probably just what I'm after but I'm in the Baldrick class here;
"I would do Sir but I don't know what you're saying".

Seems to me there's a huge hole in the market here.

Instrument displays are an exhorbitant and utterly unjustifiable £2-400 just to display one single dedicated function (ie the speed screen can't display depth info for instance - that's utterly - indefensibly nuts and a total ripoff!) - you need three or four different ones! It's no different from needing a dedicated TV set for each channel!

Thre is no reason whatsoever (apart from the cabal of the maufacturers) why one single display shouldn't show any or all of the parameters for £150 or so. Look at the complexity of an android phone - probably with the simplest of wireless interfaces you could use one of these as a multifuction display to show anyhting or everything and a £40 phone is ten thousand times more complex that a poxy Raymarine £300 single-function display unit.

So why doesn't someone come up with a device to collate all the network's data and send it, instead of to four separate £300 displays, wirelessly and selectably to an ipad/screen/pc/raspberry-pi or similar?
Costapenny -

You'd clean up selling a device like that!

What I'm after is a way to display all the Seatalk data I already have but extract it from the closed system and display it in a selectable manner on a standard pc/laptop/tablet screen. Just how hard should/could that be?

I think there's an opportunity for someone here.
 
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It's all about economies of scale. A phone manufacturer might make a million devices a month, a marine electronics manufacturer a few thousand a year. There are some costly development steps that have to be shared over vastly fewer sales - hardware design, software development, industrial design, plastic moulds, component sourcing, production setup, certification for each market, literature authoring, packaging, website/support, dealer training & of course all the other non-productive hangers-on that slurp up money in all companies like marketing, sales, IT, HR, bean counters, etc.
 
Angus, certainly that's the conventional reflex driven response.

But I don't swallow it. I'm not asing for a newly designed mobile phone.

The big cost is in developing the hardware as you say - mobile phones with a hundred times the processing power that took men to the moon now cost £40, all I'm asking for is a simple interface that will connect Raymarines (and others') Holy data into one of these cheap devices and display it in any manner the customer wants.

There is surely only a very minor hardware issue to wire the data in to the 'device' (even simpler to wifi/bluetooth it) and then write a programme to display it? That doesn't take great industrial effort - it takes a smart electronics student a bit of time and initiative!

That's so simple isn't it?

What would it require? Off the shelf probably a basic 'pi, a power source and a screen. £60 at retail prices. Plus a bit of software. But this would knock the spots of three or four far more limited commercial displays at £300 each....

Isn't this a huge opportunty for someone?
 
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What would it require? Off the shelf probably a basic 'pi, a power source and a screen. £60 at retail prices. Plus a bit of software. But this would knock the spots of three or four far more limited commercial displays at £300 each....
But as GHA says, I think you’ll find a pi and OpenCPN does exactly that
 
Oh dear. If it's as impossibly impenetrable and user unfriendly as open CPN there's little hope indeed.
The hours I've spent unable even to load a chart onto that abomination of a programme with it's uselessly unworkable 'instructions', let alone get any use out of it.
Perhaps DR is the answer after all.
 
Is it Seatalk you’re after displaying, or SeatalkNG? I assumed the latter because you also mentioned NMEA2000, and because I believe the i50 devices are NG / 2K (same thing).

Maretron are known for selling versatile generic N2k displays, though I have no experience of them myself.

Pete
 
...and then write a programme to display it? That doesn't take great industrial effort - it takes a smart electronics student a bit of time and initiative!

That's so simple isn't it?

You have already said that you are not a programmer, but you make it sound so simple, even an inexperienced unqualified student could do it if bribed with beer. You wouldn't expect a civil engineering student to design a bridge for you on the cheap. Software engineering is no different.

Software development to a professional standard is expensive, very expensive, & is not simple. Students can't & don't do it for the marine instruments we have on our boats.

I have worked developing software for a major manufacturer of marine instruments. One of the products I worked on, a display head, the cost of the software development alone was £80 per device sold. That's just one component in my list in my previous post.

If companies were able to produce marine instruments at a quarter of the price they are sold at now, some company would.

If you want to invest some money & start up a company to make a NMEA2000 to Bluetooth bridge I'll do the software development for you for £75k. I know a few hardware engineers who'll do the board design & get it through CE certification for a similar price (US certification will cost more if you want to sell it there). You'll need a license from NMEA as well. Best be sitting down when you get a quote for that.
 
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Take a look at Yacht Devices for getting your N2K data out via Bluetooth, WiFi etc.
Then you can use a mobile phone app.
I also struggled to get comfortable with opencpn. Not sure why as I bought a new laptop recently, installed it again, found some charts and then linked it to my B&G WiFi. Now have all instrument data including AIS available.
Just bought a Raspberry Pi to experiment further
Wondering if I should go with openPlotter or just Opencpn?
 
Some of the NMEA2000 display apps rely on proprietary interface But take a look on PlayStore for the free NKE app. Looks good and seems to work with any WiFi device. The least you'll need is an NMEA2000 to WiFi adapter - around £150. If you have a tablet already, that's still a lot less than a display.
 
Sorry, should have said in first reply - I think what you are looking for does already exist in almost plug and play form for not excessive cost. Unless you are a keen Pi/Arduino type, that's the path of least resistance. But maybe someone has done a DIY N2K-wifi gateway for less?
 
Yacht Devices as mentioned by Ningaloo seems to have something that works without too much technical nous required. Not overly cheap though.
NMEA to WiFi: NMEA 2000 Wi-Fi Gateway
Not tried it myself. Creating my own Raspberry Pi version for ‘fun’
With a raspberry Pi just add a canbus/usb adaptor -everything exists already in signalk/openplotter to do whatever you want with the data.
 
Oh dear. If it's as impossibly impenetrable and user unfriendly as open CPN there's little hope indeed.
The hours I've spent unable even to load a chart onto that abomination of a programme with it's uselessly unworkable 'instructions', let alone get any use out of it.
Perhaps DR is the answer after all.

With respect, if you cannot work openCPN, you're likely going to need an off the shelf solution.

You complain the Raycontrol doesn't control anything, it does. It fully controls compatible MFDs via wifi. Can be a bit clunky, but it does work.

You complain that your displays only show one thing. That's because you bought displays that, wait for it, only display one thing. An i70 will display any data from the N2K network. Garmin GMi 10s/20s will do the same.

I have Garmin GMis and they will show any data from the network. They will display data in various styles and can scroll through multiple screens. As for SOG and STW, those an be displayed simultaneously too.

No huge opportunities here, it's already been done. In fact, the Garmin displays have been around for at least 10 years. Might be worth keeping an eye open on Ebay or wherever for a secondhand display.
 
With a raspberry Pi just add a canbus/usb adaptor -everything exists already in signalk/openplotter to do whatever you want with the data.
It’s more an intellectual exercise for me. It’s running on a Raspberry Pi Zero which doesn’t have the grunt for openplotter, but doesn’t draw much power either. Currently receives and logs data. Just building a web interface exactly how I want it.

+1 for GMI20. Really like mine.
 
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