DIY Marine Onboard Network

B&G, PLEX, KODI, ODROID, tindie, OPENCPN

NERD ALERT! NERD ALERT! NERD ALERT!

We have been cruising for a full year now! After a year of cruising, you really get a chance to dial in your systems and realize which projects on that endless list are most important and which ones can wait until the next major port.

One that keeps rearing up its head is deep in that dark world of…IT.

From ship navigation systems, to where you store all of those priceless photos it a boils down to a mess of wires all a bunch of 0s and 1s. Can/should it all be linked?

Most cruisers spend lots of time far away from WiFi and even farther from our precious Netflix. Yet we all crave a bit of digital entertainment from time to time, and let’s be honest, where would we be without music on those long passages.

What we plan to do aboard Cinderella is create an onboard wifi network with a dedicated media server. The server will house all of our music, videos, TV shows, movies, and photos. Along with a dedicated media server, we will update our navigation computer and tie it to our ship instruments. The end result will be something like this.

I know, I know, it looks like a lot. But we, along with pretty much all of the boats we have met cruising already have most of the gear!

Let’s start from the top. What I called the Marine Sensor Network. The Marine Sensor Network alone can cost thousands of dollars to replace. Cinderella came with an old KVH system installed in the late 90s. The Airmar sensors still work, but all of our marine displays have since fried. One wave off the Washington coast a one year ago decided we didn’t need them.

Although it may look complicated, it’s actually quite simple. All of our instruments were designed for the NMEA 0183 standard. This standard was created in the marine industry so that different instrumentation could talk with each other. NMEA 0183 is an old standard that requires a separate channel for each input. Basically, if you wanted to interface four instruments to you computer, you would need four separate connections. It can be done, but if we use something called a multiplexer we can funnel all of the instruments through one channel to the PC.

In our situation, using a multiplexer is nice because we can also feed this NMEA information to our autopilot giving us the option to steer by the wind angle, rather than just compass direction. The NMEA multiplexer we purchased was from Quark-electric and was $144.

We purchased it while we were in Mexico, and have yet to install it. Hopefully, this project will re-ignite my drive to have ship instruments again.

Where are we so far?

We used a device called a NMEA Multiplexer to compile inputs from all of our sensors and eventually feed it to our navigation computer or what some people like to call a chartplotter. A chartplotter is basically an expensive, basic “marinized” computer that plots your boats location on a chart. Think Tom-Tom for the water. The difference between Tom-Tom and a chart plotter is usually at least crisp cool boat unit ($1000).

On Cinderella we have come to realize that marine instruments, no matter how waterproof they seem to be, aren’t. Water will eventually find it’s way inside, killing the expensive chartplotter and leaving you in a pickle. We opted instead to utilize a program called OpenCPN to handle our chartplotting needs.

OpenCPN is FREE software designed by boaters that allows you to turn any computer into a chartplotter. The perk here is that ANY computer you have onboard can now be used as a backup navigation computer after you install the application. Every computer we have onboard has it installed, though we only rely one when we are on passage. Being that it is computer based, you still have that pesky water problem to deal with.

We get around the water issue by leaving the navigation computer in the cabin at all times. As part of this ship system upgrade, we will relieve our trusty Microsoft Surface from chartplotter duty and build a custom, cheap, and watertight navigation computer.

There are, in our opinion, three basic requirements of all navigation computers. One, the computer must know where YOU are. Two, it must know where the boats around you are. Three, it must not draw too much power.

Nowadays, these basic requirements are pretty easy to satisfy. To tell the computer where we are, we have been using a cheap USB GPS dongle. We carry two in case one gets hit by water. Here is a link the the one we use on Amazon, its about $30.

To tell us where other boats are, we use an AIS receiver that receives signal from our mast mounted VHF antenna. In order to use both the VHF and AIS with a single antenna, we needed to install a splitter. Anyone who remembers the days of clunky color TVs might remember what a splitter looks like. Here is the one we have installed onboard Cinderella, it was about $70.

We really liked the Microsoft Surface for use as our navigation computer. It has a large touch screen monitor, it has a nice fold down keyboard and a neat bluetooth mouse. Unfortunately, that wave that killed our marine instruments also got to our Surface, and ever since it takes a little TLC to start it up and keep it going. It had a hard year, and it’s time we come up with something new to replace it. We are currently looking at simple 12V computers like the RasberryPi or Odroid. They are both small, low power, and can be sealed into a watertight box and stowed in a small cabinet.

Along with the computer, we will need to find a low draw 12V monitor and a simple bluetooth keyboard and mouse, but I believe the new navigation PC could be had for $200-$300.

So now we have our boat instruments connected to our navigation computer, but one major piece remains. The media! What about the music/TV shows/movies? The last piece of the upgrade is the NAS or Network Attached Storage server. What we will call the Cinderella Cloud.

The Cinderella cloud will be essentially made up of three pieces, a hard drive (where the media will live), a NAS server (means to organize the media), and a router (means to share the media with all of our devices).

We have had a small router onboard since before we left Seattle. I read a cruising blog a long time ago and decided to purchase a WiFi extender so that I could pick up WiFi at the marina from far away. Along with the WiFi extender, I purchased a 12V router to allow all of my devices to utilize that WiFi.

We plan to buy a 12V NAS server from Odroid, and pair it with a large capacity, low draw hard drive.

These hardware components don’t mean very much alone, but with the help of neat media software (Plex or Kodi), we should be able to connect to the Cindy Cloud and scroll through all of our movies, TV shows, or music at any time from any device and stream away. It will be like our own little onboard Netflix!

If everything goes to plan, we should have an entire onboard network integrating marine instruments, a navigation computer, and a media server, all for less than the cost of a standard chartplotter!