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  • Capt. Eric

Back to the Future

With our old obsolete GPS units that couldn't be upgraded anymore it was time for a serious refresh of the electronics in our pilothouse. The old GPS had reached their end of life as their almanac was out of date and could not be refreshed via firmware. This meant that they could not predict (calculate) the position of upcoming satellites. So, they'd take a very long time to receive a GPS signal, and would lose it fairly easily, often at the most inconvenient moment. Going under a bridge would trigger satellite loss, and it could take a whole 30 minutes to re-acquire enough satellites to get a good fix again.

So on the "while we're at it" principle we had a number of electronic upgrades done:

-2 brand new Furuno GPS units. These can also store and receive waypoints and routes from other units and computers around the boat.

-A NMEA 0183 (the navigation network) to ethernet bridge so any machine on our intranet can now receive and decode the navigation information.

-A new 360 TV antenna connected to an ethernet tuner. Similar to the navigation network, this means the TV signal is now available to any client, be it computer or Android machine, on the ship's intranet.

-An auto-start unit for the generator. It detects the state of charge and/or voltage and status of the batteries and starts or stops the generator automatically. The unit is made to work with our existing Magnum inverter and charger, its battery monitoring kit, temperature sensor and remote control. That means it can be set to do real clever things like start on high inverter demand, so that starting the microwave for example can trigger a quick run of the generator to assist in producing electricity for the temporary high demand.

Or, more simply, charge the batteries when they are low and stop when they are full.

The unit can consider quiet times (times at which the generator will not run), and calculate when it needs to run to comply with quiet time yet still leave the batteries charged.

-New chart for the existing Furuno video chart plotter.

-New Raymarine wind instrument connected to the navigation network via a NMEA 2000 to 0183 interface. Having a "new" NMEA 2000 interface means we can now more easily integrate additional sensors and NMEA 2000 instruments on the network.

That being said, I remain old school and tend to prefer the older 0183 standard as it is still the one in use in most commercial applications.

Some NMEA sensors such as fuel and water gauges could be neat later on though.

Receiving navigation data on a computer and tablet

After playing with and testing a number of apps and programs I settled on OpenCPN both for Android tablets and Windows computer. It's an open source chart plotter software with very powerful features and a number of really good plugins to import weather data and many other useful functions.

2 new Furuno GPS units being installed

Android tablet running OpenCPN and receiving wind. AIS and depth data

I repurposed an old 2009 Sony laptop by installing a special version of Android, then OpenCPN and presto, it connected to the network and provides me an additional 12" screen chart plotter. "Free" chart plotter!!

OpenCPN is also running on the desk's computer, which means during navigation we can see our position, route, AIS targets and more on the larger monitor there. Di loves that as she can be in the galley or salon and still know where we are!

OpenCPN running at Enfin's desk, visible from the galley and salon

Enfin just jumped into the future, and with my habit of having backup solutions, I now have 3 chart plotters running different charts on bridge. Routes are sent to both GPS, and one is chosen as the main navigation unit, with the other one being ready to take over if needed.

The autopilot can then receive NAV (automated navigation information) from the chosen GPS or via a switch on the console, any of the OpenCPN machines.

There's something weird, eery and magical seeing Enfin negotiate a river turn all by itself following a per-determined route. Of course one can't trust the route fully without close monitoring. In our first try, the route went right through an anchored bulk carrier, and the autopilot would have happily taken us right through it!

The route went through the bulk carrier! Better keep an eye on things

Whether this is more or less dangerous than more traditional navigation is up for debate. I've investigated accidents where the autopilot took a ship right over a sunken jetty, and another straight into a reef. But I've also investigated accidents where an automatic course change would have saved the ship from running aground, or at least alerted the watch officer a turn was coming up.

On Enfin, the autopilot will change course less than 10 degrees by itself, but alert and scream when the course change is over 10 degrees. It's a compromise solution, and the simple answer is to remain as vigilant as without all the clever automation.

We couldn't resist testing all the new gear and functions and took the boat out for a great little cruise down to St Helens Marine Park.

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