Has the PC finally come of age? – a review of OpenCPN

Hurricane

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Most reading this will know that I’m very keen on PC navigation software. Anyway, I’ve spent some of the winter evenings re-visiting the software that I use and I thought that I’d share my findings. Some readers may see this as a boring subject but others might find this thread useful if a very low cost chart plotter is required.

On the boat, I make extensive use of the PC but it has always been “in addition” to the boat’s dedicated navigation systems – not “instead of”. During installation of my Raymarine G Series systems, I incorporated PC feeds throughout the boat. This meant that I could run PC based software alongside the professional, more robust equipment. Initially, it was just as an experiment, but over the years, I’ve become more confident. Right from the outset, passage planning and route input was done on the PC. The software systems that I use have a method of “uploading” routes/waypoints to the Raymarine systems which then handle the “in passage” navigation. The PC also has a GPS feed to it so during the passage, it can keep a good “watch” of the boat’s progress and create a graphical historical log. I often show these logs in the chartlets that I post in my little blog reports. My Raymarine kit uses Navionics and the PC uses various raster format charts so I’ve always got a comparison from different chart suppliers. The PC is controlled using a wireless keyboard and an “air mouse” – the range is 30m so one keyboard and one mouse will work throughout the boat – for the mouse and keyboard that I use see here http://www.gyration.com/index.php/us/products/in-air-micekeyboards/go-air-mouse.html#models

So, where is it all going?

PC navigation isn’t a new thing – there are loads of different systems out there. This winter, I’ve spent some time re-evaluating my PC software. At the moment, I use Memory Map which is an excellent Windows software package sold for walkers to use in the mountains. Personally, I believe that the author of the software owns a boat (why else would he incorporate AIS!!). The software is the fastest I’ve ever seen at drawing on the screen. The QCT file format that is native to Memory Map incorporates an interlace technique so it doesn’t need to read all the data when displaying larger scale charts. The result is blisteringly fast scrolling and panning. However, recent versions of Memory Map now require internet connection to register itself and its charts. Cheekily, it even requires you to register charts that you’ve scanned in yourself!! Personally, I will have nothing to do with any software to be used at sea that depends upon an internet connection so I’ve simply not upgraded. At the moment, charts are still available in BSB format and the old software reads them as it did before.

We all like to keep costs down to a minimum so, a few years ago, I looked at an Open Source application called OpenCPN (see www.opencpn.org ). Open source software development is usually carried out by a team of enthusiasts that provide all their work for free. When I looked at OpenCPN a few years ago, it was very crude but over time, it seems to me that it has matured and is now a very useable solution. A very active user community now exists (see this forum http://www.cruisersforum.com/forums/f134/ ) and in fact the latest “beta” test version was released only a few days ago – full of bugs but this shows its continual development. No software is absolutely “bug free” but there is a stable version available which works very well and is suitable for active use. OpenCPN now reads several different chart formats including the older BSB raster charts and CM93 vector charts. In fact it has a really nice feature that “quilts” charts in any format so, for example, you can seamlessly display an Admiralty raster chart alongside a vector chart on the screen at the same time.

Another great feature of OpenCPN is that it is available for Windows, most Linux systems and they have just released a version for the MAC. Maybe smart phones (Android etc) could follow – who knows?

So, this winter, I put my mind to running OpenCPN alongside my Memory Map software. My concern is that I can’t (won’t) upgrade to newer versions of Memory Map so I might need something else as technology evolves. Firstly, I needed to get my charts (my own scanned charts) from Memory Map’s QCT format into the OpenCPN format. To cut a long story short, I ended up writing a conversion utility to convert QCT files into BSB format that could then be read directly into OpenCPN. Memory Map incorporates a really neat map calibration tool so my conversion program outputs all the geo-referencing information as well thus keeping the transfer procedure accurate and to a minimum. This now makes OpenCPN a very useful tool.

You may have read a thread that I posted a couple of weeks ago on a delivery trip I did recently with John from Gibraltar to Sant Carles. The boat was new to John, so we weren’t sure how good her navigation systems would be. We both took extra navigation systems with us. I took my Windows Netbook PC fitted with a GPS dongle that I bought from Amazon for about £17 – see here http://www.amazon.co.uk/Bluenext-BN...KZOQ/ref=sr_1_1?ie=UTF8&qid=1300046948&sr=8-1 . Memory Map was installed with a set of raster charts and OpenCPN with raster and vector charts. I was interested to see how well both systems ran from a low cost PC notebook. John took his iPad with the low cost Navionics app installed.

John’s new (to him) boat has a standard ST6000 autopilot control head at the lower helm and a wired hand held controller on the flybridge. I’m sure John will eventually sort everything out but there seemed to be something intermittent with the flybridge unit so we opted to control the pilot from the lower helm. It was also very difficult to read the displays of the old monochrome RL70s so we decided to just press “Auto” and manually steer the boat using the +1 +10 -1 -10 keys rather that let the pilot read a route from the RL70s. I sat at the lower helm and by manually adjusting the autopilot, I got the boat to follow the route that the PC was indicating. In fact, navigating this way was really easy and very accurate.

This technique gave me a very good opportunity to test the difference between my “old faithful” Memory Map and OpenCPN software. It became clear quite quickly that OpenCPN is very capable and has been designed specifically to navigate a boat. The next waypoint is identified by flashing a red/yellow circle and the heading by a leading red line terminated with a small red box. Although I haven’t tried it yet, the system can be connected directly to an autopilot and made to follow routes just like any dedicated commercially available plotter. It also accepts input from an AIS receiver. There isn’t much it doesn’t have and remember, it’s free.

So what will I be doing in the longer term?
A link on the OpenCPN website takes you to another free software product called VSPE. This really neat software application for Windows allows multiple applications to access the same serial port (USB or Legacy RS232). It can also act as an IP server for the serial ports so I have installed in on Jennywren’s main computer and shared the NMEA data streams to the onboard WiFi LAN. Sounds a bit complex but this means that I can then pick up all the ships data on my Windows Notepad PC. So OpenCPN and Memory Map navigation software along with my anchor alarms and talking logging systems are available on the Windows Notepad PC. This upgrade to my system is a completely software – no extra hardware required. In fact the concept goes along with everything I’ve done on the boat. Take away the PCs and the boat operates exactly the same as any other.

Here are a few screen dumps to show some of the features. I apologise for some of them which were taken with a camera in a bouncy sea so are a little fuzzy.

The first shows the basic display with “quilting” turned on. Notice the significantly different chart formats – the left and top is displaying a vector chart whilst the lower right side of the screen shows a raster chart. Area is Palma Bay in Mallorca.

Quilt_Vector_Small.jpg



And here’s another screen dump of the same area with a second raster chart on the left – the top is still showing the vector chart.

Quilt_Raster_Small.jpg



The following screen shot is OpenCPN underway – showing vector charts. Note the next waypoint circle in red/yellow and the ships icon with the heading line and leading square graphic.

In_Use_Route_Vector_Small.jpg



In the next screen shot the route hasn’t yet been activated so there’s no next waypoint but you can, again, see the chart quilting working.

In_Use_Quilt_Small.jpg



And for those who like to see their charts “head up”, OpenCPN has an option. Personally, I prefer to have my chart plotter displaying North Up so that I don’t get confused in case I have to revert to a paper printed chart.

In_Use_Head_Up_Small.jpg



And the following is another screen shot under way – the red/yellow circle flashes and this shot was taken between the flashes so the next waypoint isn’t shown as well as the screen shot above.

In_Use_Small.jpg



more in next post.......
 
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Continued...

Whilst following a route, the system shows a “rolling road” information window. This window can be set to display route or leg information. So the following graphic shows that we will finish the route at 10:38 – Time to go to end of route is 39 mins 28 secs.

In_Use_Route_Vga.jpg


In the next shot, I’ve clicked the “Leg/Route” button to get this window showing all the information about the current leg – XTE (Cross Track Error) and time to next waypoint of 29 mins 22 secs.

In_Use_Leg_Vga.jpg



This screen dump shows OpenCPN’s AIS screen. I generated this screen at home using a cheap NASA AIS engine connected directly to a PC serial port. The “Own Ship” logo was placed manually – a GPS input would have been meaningless for this demonstration example.

AIS_Small.jpg



Finally, for a bit of fun, I’ve been playing with Google Earth images. Using a graphics editor, I’ve overlaid a Google Earth aerial photo onto a raster chart. By carefully blending layers, I was able to get this result – a permanent new chart which can be used alongside the unaltered one – no internet connection necessary. Again, no extra geo-referencing was necessary because the underlying chart was already geo-referenced.

Again, OpenCPN has quilted two charts – one on the left and the one with more detail and Google Earth image on the right.

Google1_Small.jpg



And finally, a zoomed version of the same chart. This one is particularly interesting – you can see all the navigation information (lights and depths etc) on the same chart as the Google Earth shore detail.

Google2_Small.jpg


And then, the same with our track (the purple line) when we visited Valencia last summer.

Google3_Small.jpg


As I say, maybe you will find this post a bit boring but I thought it would be interesting for some people. I have absolutely nothing to do with OpenCPN or its development but it’s been an interesting winter exercise to see how it has developed over the years.
 
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Excellent post. I have started using OpenCPN in the past year and have found it excellent. I had been using Software ON Board with CMAP Max charts but found the lack of updates to teh software frustrating with bugs never getting fixed.

After changing to OpenCPN I just loved the user interface and the night mode is the best around.

One thing I found very useful is customising the size and font of all the on screen data. I made the route information text larger and used a different font and the changed the AIS display popup for easier viewing in a rough sea.

These chart overlays looks great, very similar to the Navionics Android App where you can overlay Google Earth or Maps imagery for the land sections though requires a data connection.
 
Thank you. Excellent post, very informative!
I use Tiki navigator gold, and it uses the raymarine charts on a card reader, could I use these charts with Opencpn? Donmt want to be buying more charts! I really like the google earth overlays, they look marvellous. I'm only just starting down the pc navigation road and tiki works fine for me, but would like more and better information on my charts. I have AIS, SSB and navtex going into the computer also. I just dont have the time to work through it all. Maybe this year, but I doubt it.
 
great post.

I have been disappointed with the usual raymarine bits on Ellle an have thought about looking at PC alternatives but wasnt sure where to start. I hadnt looked at nav software for a long time but that seems to have brought me up to speed very quickly. I will definately be getting one of those mouse gizmos! and may try some of the software out. thanks again.
 
One thing I found very useful is customising the size and font of all the on screen data. I made the route information text larger and used a different font and the changed the AIS display popup for easier viewing in a rough sea.

I've never played with the font size before. Its often good to discuss software that you use with other users. It's often the way that you get to learn new features or features that you've missed.
I had a quick look at the fonts and set all the options to a larger font.

Here's the AIS picture in the Channel TSS this morning - this time with bigger fonts.

AIS2_Small.jpg


Currently using the beta test version of OpenCPN
 
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Very interesting posts, hurricane. I must admit that I'm not yet into PC navigation although I did have some PC based chart software a few years ago but which I gave up on because it was so clunky to use.
I've got some general questions about PC navigation which may sound a bit simple but I'm not a computer geek. Do you find your chart cartography better or worse than typical C Map or Navionics plotter cartography in terms of accurate detail or in other ways? You say you upload routes from your PC to the on board plotter system. How do you do that and how easy is it? Do you need to have specified the interface from the outset or can that interface be connected to any plotter?
Lastly you say you use a netbook. How do you handle issues of battery usage, vibration and protection from moisture? Do you have to charge the netbook periodically with the gennie, does it just sit at the helm station on its own or do you have some kind of cradle? Do you take it up onto the flybridge and what happens if there is spray about? What about rough sea conditions?
 
Very interesting posts, hurricane. I must admit that I'm not yet into PC navigation although I did have some PC based chart software a few years ago but which I gave up on because it was so clunky to use.
I've got some general questions about PC navigation which may sound a bit simple but I'm not a computer geek. Do you find your chart cartography better or worse than typical C Map or Navionics plotter cartography in terms of accurate detail or in other ways? You say you upload routes from your PC to the on board plotter system. How do you do that and how easy is it? Do you need to have specified the interface from the outset or can that interface be connected to any plotter?
Lastly you say you use a netbook. How do you handle issues of battery usage, vibration and protection from moisture? Do you have to charge the netbook periodically with the gennie, does it just sit at the helm station on its own or do you have some kind of cradle? Do you take it up onto the flybridge and what happens if there is spray about? What about rough sea conditions?

Lots of questions there, Mike

Charts
The beauty of PC nav software is that you are not tied to any particulat chart supplier. OpenCPN is very good in this respect because it handles CMAP vector charts and BSB raster charts.
I like to have complete control over my charts - to the extent that I like to have the ability of scanning my own. For example, this is an extract of a chart of the Columbrete Islands that I bought locally. I then scanned it in and georeferenced it using Memory Map's calibration facility. Then using my own conversion utility, I exported the chart to OpenCPN.
The point I make is that the charts are as good or as bad as you want - you have the choice.

Columbretes_Small.jpg


Uploading
Uploading routes is fairly simple. My experience is with Raymarine but most (if not all) plotters have a NMEA interface which feeds GPS data out. I use the same channel to send the data back. You can safely connect a PC's RS232 to the plotter but my on board system is a little more sophisticated, using one of these http://www.actisense.com/HTML/Products/Gateways/USB to NMEA 0183 Gateway/index.php which provides protection and converts NMEA into a USB for the PC.
At the moment, I use Memory Map to "upload" but I dont see why OpenCPN couldnt be used in a similar way. Once set up, I create a route by simply clicking and "rubber banding" with a mouse - then I "right click" the route and a sub menu appears with a menu item "Send to GPS" - the Raymarine system needs to be set up to "listen" first but the whole thing is done in a matter of seconds.
Similarly, you can create and store a "database" of favourite waypoints on the PC and upload them to the plotter. For example, I often delete my plotter waypoint list and re-upload whenever I want. A sort of backup.

Netbook
Actually, the netbook itself isnt very good for everyday navigation - the screen isnt bright enough and the whole thing isnt robust enough. My point is that a PC in some form is a really great planning tool which can be integrated into the system and provide very good additional information.
On my recent trip with John, I had the Notebook PC on the seat beside me at the lower helm. I have a 12v cigarette lighter style power supply which kept it running all the time. However, the Notebook PC I bought has a 10 hour battery life. Once at anchor, the same software can be used as an anchor alarm - I keep mine beside the bed for peace of mind at anchor.
 
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Fantastic Thread full of great information. I have been using OpenCPN with CM93 charts but have memory map and have .qct charts. Could you please tell me how to get hold of your .QCT to .BSB convertor tool.
 
Excellent - I see you are using the Dashboard plugin as well.

Yes I am, I've got a small touch screen monitor for under my sprayhood and am using it as a "chartplotter" also.

Thanks for your enjoyable review by the way, I have been using opencpn for a fair while now and am particularly pleased with the open development model.

A few of my suggestions have made it to the finished programme, if you have any suggestions just post them on the forums linked by Hurricane above, or directly into the feature tracker here :)
 
Yes I am, I've got a small touch screen monitor for under my sprayhood and am using it as a "chartplotter" also.

Thanks for your enjoyable review by the way, I have been using opencpn for a fair while now and am particularly pleased with the open development model.

A few of my suggestions have made it to the finished programme, if you have any suggestions just post them on the forums linked by Hurricane above, or directly into the feature tracker here :)

I would be interested to hear what monitor you are using - is it any good in sunlight etc...
 
Its quite a cheap VGA monitor that runs directly off 12 volts, its not great in daylight - under sprayhood in shade its not too bad (otherwise retreat to nav station). I am looking around for a suitable replacement.

I have seen positive reports about toughbook monitors, which are apparently used in US police vehicles and thus widely and cheaply available:

http://cgi.ebay.com/Panasonic-CF-VD...929?pt=LH_DefaultDomain_0&hash=item588cd45dc9

Other than that, daylight compatible, waterproof, 12 volt monitors cost an absolute fortune!
 
Very interesting stuff Hurricane. It's interesting because the software appears to be very comprehensive and powerful whereas traditionally PC navigation software has been lacking.

However, I would most definitely not want a PC based system as my primary navigation system. They are just not reliable or rugged enough for use on a boat especially if long or night passages are planned in potentially rough weather.
 
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