OpenCPN hardware from scratch.

[GILow]

Hi all,

I am putting together my first OpenCPN system from scratch. It will be the primary navigation and instrument system for our Kelly Peterson 44, mostly doing coastal cruising but some longer ocean passages from time to time. (Backup is Navionics on tablets with gps.)

Plan is to drive two displays, one daylight-readable and moderately waterproof touchscreen for the cockpit (well sheltered) and one extra display downstairs using the TV and a cordless mouse/keyboard.

Probably a Simrad Radar, one of the current Halo models, they seem to be the most reliable these days. (Well… fewest complaints anyway.)

Depth, speed, wind temp, gps, heading etc using generic Airmar or similar N2K instruments.

So, which computer would you buy? I’m assuming something like an Intel NUC? Budget is not tight, but it’s not silly either. I don’t need a gaming PC on the boat, just something that will drive OpenCPN as smoothly and reliably as possible.

I’m happy to assemble from scratch if that’s the smart way to go, but happier to buy a good packaged system.

Ideas? Specs?

Matt

[barcoMeCasa]

Raspberry Pi 4 gets my 110% vote. 2 monitor outs, plenty fast enough, cheap enough to have a 2nd one ready to swap. Openplotter makes the setup easy & includes signalk which can do anything with data on a boat, allows you to get at inexpensive but verry accurate non nmea sensors for temperature, barometer & battery logging.
Been running Pi's for many years, openplotter software rock solid for a long time & never had a Pi failure which wasn't down to exceptional user stupidity .

I use a Pi 3 which is a bit slower but still useable & the lower power means it never gets turned off with opencpn running all the time with track enabled, very useful to keep an eye on things in the anchorage. Halo plus is excellent!

[GILow]

Originally Posted by barcoMeCasa

Raspberry Pi 4 gets my 110% vote. 2 monitor outs, plenty fast enough, cheap enough to have a 2nd one ready to swap. Openplotter makes the setup easy & includes signalk which can do anything with data on a boat, allows you to get at inexpensive but verry accurate non nmea sensors for temperature, barometer & battery logging.
Been running Pi's for many years, openplotter software rock solid for a long time & never had a Pi failure which wasn't down to exceptional user stupidity .

I use a Pi 3 which is a bit slower but still useable & the lower power means it never gets turned off with opencpn running all the time with track enabled, very useful to keep an eye on things in the anchorage. Halo plus is excellent!

Hadn’t considered Pi. Thank you for flagging it as an option.

[wholybee]

I am going to vote against the Pi. Unless you have used them and/or Linux in the past and are comfortable with them. They are a great option for makers/tinkerers/and those that do everything they can to only use opensource. They work fine, but it's going to be a lot more work to get running, and you add a whole lot more variables where stuff can go wrong. Just look at how much support there is here given to rpi and Linux. Yet, I bet there are more OCPN users on Windows and the Mac.

An intel NUC or similar tiny PC will work, but I recommend a laptop. It will be the fastest and easiest way to get it going. Buy a NMEA to USB converter (I prefer the wireless ones so they also work with a tablet) and skip SignalK. For anything 99% of what boaters want/need, OCPN will get the information fine without it. Install SignalK when you decide to replace your airmar stuff with brandless cheap stuff from ebay, or if you decide you need to control your engine from your navigation system.

One factor for me early on was ease of replacement if it fails in a remote spot. I was looking for a pi5 last week, and they seem sold out again, at least if you don't want to pay inflated prices. Now imagine getting one in Fiji or Indonesia. You can buy a brand new laptop from a store shelf almost anywhere in the world, and if you are familiar, from open box to working chart plotter is under an hour. Keep an external drive with a backup copy of the install files and all your charts, so you can get it up again very quickly.

The monitor at the cockpit is the expensive part, if you get a decent one. I would probably use Displayport to Cat5 extenders. A few of these (expensive) will also take USB for a keyboard/mouse input. Displayport and HDMI both are sensitive to long cable runs, unless you use very heavy expensive cables. The Cat 5 extenders gets around that. Or, you could run something completely separate in the cockpit (A tablet etc.) and mirror the screen with VLC or Windows Remote Desktop.

FWIW, I circumnavigated with a $300 laptop from Office Depot. I brought 2 of them figuring 2 $300 laptops would be more reliable than 1 $600 laptop. I never needed the second one. Be sure to use a bit of dielectric grease on all the connectors. I did have that problem after a couple years, that my USB connectors are now a bit flaky if the cable moves. Did I mention NMEA over wifi, and not USB?

The other advantage of a laptop is that you probably already have one. Get it setup, go sailing with it, and then if you then you find you want something else, you can switch having not wasted any money.

[GILow]

I understand your suggestion, and I've got a laptop already and I have OpenCPN on it. But I really do not like laptops for anything other than a backup roll. I want a bit of hardware that is weather-proof and solidly attached to the boat for when things go to s--t.

I do not want to be chasing a laptop all over the cockpit while trying to navigate a tight, rolly channel at night.

25 years of sys admin roles using countless Unix variants has left me comfortable enough with the idea of a Pi based solution, however the main concern I have with that platform is the graphics performance. I want this system to be reasonable sprightly and smooth when scrolling and zooming. I think I will try a Pi, it's a cheap experiment. If the performance is good enough then I've saved a lot of money, if not I haven't wasted a lot.

[wholybee]

Originally Posted by GILow

I understand your suggestion, and I've got a laptop already and I have OpenCPN on it. But I really do not like laptops for anything other than a backup roll. I want a bit of hardware that is weather-proof and solidly attached to the boat for when things go to s--t.

I do not want to be chasing a laptop all over the cockpit while trying to navigate a tight, rolly channel at night.

25 years of sys admin roles using countless Unix variants has left me comfortable enough with the idea of a Pi based solution, however the main concern I have with that platform is the graphics performance. I want this system to be reasonable sprightly and smooth when scrolling and zooming. I think I will try a Pi, it's a cheap experiment. If the performance is good enough then I've saved a lot of money, if not I haven't wasted a lot.

If you have UNIX experience then go for it. It'll be a fun project. My laptop never left the chart table. You definitely don't want it in the cockpit.

[HeywoodJ]

I've been using a Pi with OpenCPN since 2015. The current iteration is a Pi400 because it gets rid of the keyboard cable. OpenCPN with raster charts is fantastic on the Pi. Easy-peasy, done deal. Pretty much the same with long-in-the-tooth CM93. I find it not quite so snappy with new vector charts (which nearly all current charts are). It really depends on the number of cells for your locale. With a few there is no problem, but with lots of detailed cells (i.e. first world areas with lots of detailed charts) I find it acceptable but not stellar. You will see, from time to time, some lag that can get annoying. Reminds of working on computers 20 years ago.

I would do it the same way again, but understand it is definitely a moderate computing power platform. YMMV

[markrsimon]

Also take a look at the HP ProDesk 600 G5 mini (or other flavors). Small form factor and nimble. Challenge is the DC power. You need a dc-dc convertor and a resistor on the center pin.

[barcoMeCasa]

Originally Posted by wholybee

I am going to vote against the Pi. Unless you have used them and/or Linux in the past and are comfortable with them. They are a great option for makers/tinkerers/and those that do everything they can to only use opensource. They work fine, but it's going to be a lot more work to get running, and you add a whole lot more variables where stuff can go wrong. Just look at how much support there is here given to rpi and Linux. Yet, I bet there are more OCPN users on Windows and the Mac.

Have to disagree with that. Copy openplotter onto an sd card, put it in a Pi and turn it on. Menus for everything. Actually easier & quicker to get opencpn up and running than windows.
https://openplotter.readthedocs.io/e...nstalling.html

No need to know anything about Linux or tinker any more than you need to be a Windows guru to run opencpn on a laptop. , that's the whole idea. Keep a backup card just in case, not something that's possible on windows.

Look at openplotter support, virtually no issues with the stock image, it just works & will run 24/7 week after week.

Hardware is a little more involved with needing a good 5v usb c supply, cooling fan and a case, can't expect everything for $60 for a 4gig pi4 off amazon

Think a lot of people get put off by doom n gloom posts on the Web.

[barcoMeCasa]

Originally Posted by GILow

however the main concern I have with that platform is the graphics performance. I want this system to be reasonable sprightly and smooth when scrolling and zooming. I think I will try a Pi, it's a cheap experiment. If the performance is good enough then I've saved a lot of money, if not I haven't wasted a lot.

Pi4 should be fine, this is a Pi3 running over vnc, usable but bit slow & clunky, pi4 on a monitor is totally different beast , far faster.

[GILow]

Originally Posted by barcoMeCasa

Pi4 should be fine, this is a Pi3 running over vnc, usable but bit slow & clunky, pi4 on a monitor is totally different beast , far faster.

Good to know, thank you. (VNC brings back some memories… most of them painful.)

[barcoMeCasa]

Originally Posted by GILow

Good to know, thank you. (VNC brings back some memories… most of them painful.)

VNC seems fine these days, preinstalled in openplotter.

I actually have a couple of Pi 4's onboard but the Pi3 is fast enough to be plenty usable and doesn't draw much power so can can be left on all the time. Really handy for me living anchored full time as any mobile phone / tablet can have a quick look check the hook hasn't moved. Plan to fit a relay to the radar switchable over WiFi so 3am if there's an anchor chain running which sounds too close I can turn on the radar and have a quick look around on a tablet without getting out of bed

[Tupaia]

I have been using a mini PC for nav for best part of 20 years. The latest incarnation is an ASRock BeeBox. I chose one of the lower performance processors N3000 series which is more than capable of running Opencpn and other Nav software and has very very low power consumption. Teamed with a 24in low power monitor inside and a professional camera monitor in the cockpit. Wireless handheld keypad/touchpad works fine in cockpit and standard keyboard/mouse pad inside.

Tried a touch screen but found the interface not brilliant or reliability with wet hands. Have wifi multiplexor that allows most instrument data to be relayed to an android phone.

Being able to turn off monitors and leave PC running limits the power consumption.

Radar plugs in directly RJ45 but all other instruments are stand alone did not like the idea of using just transducers, loosing all information if PC goes down or even reboots at a vital point. Considered using a ruggedized windows tablet in cockpit but is expensive so jury is still out on that option.

AIS operates completely standalone meaning it can be left on when everything else is shut down giving AIS, GPS and anchor watch.

[cas206]

If you are interested in going beyond just a chart display, take a look at signalk.org, or https://github.com/SignalK/signalk-server. OpenCPN has the ability to read from a signal k server built in. I just started going down this rabbit hole. I installed Signal K server on a PI 3B+. So far I've only connected a USB GPS puck to the server to test reading it over a Wifi connected laptop with OpenCPN. That works fine.

Some sites I've come across that you might find interesting.
https://open-boat-projects.org/en/
https://bareboat-necessities.github.io/my-bareboat/

I've got a Raymarine Seatalk NG (i.e. NMEA 2000) backbone connecting the components of a wheel autopilot installed. I'm interested to get that connected to the server and see what I can do with it. With the GPS, the desire is to add course over ground as a pilot option in addition to fixed heading. Also shopping some wireless wind instruments.

I'm also shopping for a device to act as a waterproof display in the cockpit. Not found any good options yet. Options seem to be divided into brand name devices priced in the "ouch" range, or Alibaba.com

[JeffBurright]

On the display front, I've seen some people are starting to use inexpensive Android car stereo heads. I wonder how well that would do with either a native Android OpenCPN running, or used as the monitor interface for a Pi inside the cabin. I also wonder how well it could be weatherproofed.
Here is the thread: https://forums.ybw.com/threads/my-co....540255/page-6