AIS Class B Tracker Options and Tips?

[Jack Hales]

Hi all,

I’m new to the forums, and I’ve joined as I think some people on here may be able to help me with something. I’m currently doing my A-Levels and one of those is an Extended Project Qualification (EPQ). My plan for this is to investigate and research different AIS Transponder options for the school’s keelboats, and then ultimately install the chosen option and embed a map / tracker onto the school’s website.

From my preliminary research, I need to look for AIS Class B transponders. I’ve found a few online, all with varying prices and I’m not sure what would be best. On top of that, I can’t find many reviews of products either. I thought that there would be some people on this forum who have some experience in this field, so if you have any tips / suggestions for AIS Class B transponders, what to look for, what to avoid, that would be greatly appreciated.

Thanks a lot, Jack

 

[C08]

I am watching this with interest as I plan to get a AIS transponder-come on guys help the lad!

 

[laika]

Step 1 is to define what you want to achieve. AIS is not necessarily the best option if you just want to embed a tracker on your website. For AIS you'd need to install an antenna, GPS receiver and enough power to power the unit. You'd need an additional AIS receiver (onshore?) to receive and decode the signal unless you want to rely on the signal being picked up by hobbyists and relayed to an aggregation site like marinetraffic (which you'd then have to interface with to extract tracking data). You've also got a fairly valuable lump of equipment on each of your keelboats which may present security issues on a keelboat (if I understand the term "keelboat" correctly in this context).

For simply tracking, you don't need to be broadcasting your GPS data over VHF: you could dispense with the VHF part entirely and connect a GPS unit to a GSM board and send your GPS data directly over mobile Internet or via sms. Or buy a commercial GPS tracker unit. *Much* easier to install, much lower power (so you don't need massive batteries), much cheaper and small enough to conceal better. Moreover *IF* you need data in AIS format, it's then a straightforward programming exercise to convert GPS data on a receiving computer into AIS data:
AIVDM/AIVDO protocol decoding

If AIS (over VHF) is an end in its own right for pedagogical reasons, do obviously be aware of the differences between classes, including the new SOTDMA class B. Digital Yacht have a short and accessible paper on this:
https://digitalyacht.net/wp-content/uploads/2018/11/Class-B-SOTDMA-AIS-White-Paper-V1_01.pdf
I'm guessing you won't have reason to need anything more than the cheapest old style CSTDMA class B.

If you really do want to go with AIS, look for something at the cheap end of the spectrum, look at the power consumption, work out what size of battery would power it and for how long, look whether it's waterproof, think about where you'd install it and how you'd stop someone nicking it if it can't be locked away.

But a little GPS tracker sending data over mobile Internet which can be easily plotted on a website or (if necessary) assembled into AIS data on a receiving computer might be simpler/cheaper all round

 

[Spirit (of Glenans)]

The Digital Yacht range seem to be the most popular. I don't know whether this is based on functionality or price.
I'm sure you know that these devices come as a 'black box' which must be connected up to a chartplotter and other devices, thus you will also have to investigate this aspect, e.g NMEA connectivity protocols etc.

 

[laika]

I'm sure you know that these devices come as a 'black box' which must be connected up to a chartplotter and other devices, thus you will also have to investigate this aspect, e.g NMEA connectivity protocols etc.

Not unless they want to use the receiver for collision avoidance onboard, the utility of which would be questionable if I am correctly understanding what is meant by "keelboat": ie sailing boat with a keel rather than centreboard but not necessarily any accommodation, used largely for inshore daysailing. If the objective is simply broadcasting AIS data, receiving it elsewhere and plotting it on a website the AIS unit, GPS, antenna, coax and power is all that's needed. And per previous post you don't even need the AIS unit if you do it over mobile rather than VHF

 

[[70521]]

Hi all,

I’m new to the forums, and I’ve joined as I think some people on here may be able to help me with something. I’m currently doing my A-Levels and one of those is an Extended Project Qualification (EPQ). My plan for this is to investigate and research different AIS Transponder options for the school’s keelboats, and then ultimately install the chosen option and embed a map / tracker onto the school’s website.

From my preliminary research, I need to look for AIS Class B transponders. I’ve found a few online, all with varying prices and I’m not sure what would be best. On top of that, I can’t find many reviews of products either. I thought that there would be some people on this forum who have some experience in this field, so if you have any tips / suggestions for AIS Class B transponders, what to look for, what to avoid, that would be greatly appreciated.

Thanks a lot, Jack

Hello and Welcome Jack

As a grumpy old engineer I'd like to understand what you mean by "Transponder Options?"

As you state the school has keelboats, that covers a big selection of vessels. Can do define the area that the vessels will be sailing in.

Fundamentally, all Class B transponders have three basic options:

1. Off
2. On - Receiving only
3. On - Transmitting and receiving

Some may integrate with a compatible VHF DSC radio and that is about it.

Good luck with your son's EPQ, What does he plan to do following his A Levels?

 

[pvb]

Good luck with your son's EPQ, What does he plan to do following his A Levels?

I think Jack's the one doing the EPQ.

 

[prv]

Good luck with your son's EPQ, What does he plan to do

Think you've skipped a generation there. It may not always feel like it, but not everyone on this forum is an OAP

Pete

 

[LadyInBed]

But a little GPS tracker sending data over mobile Internet which can be easily plotted on a website or (if necessary) assembled into AIS data on a receiving computer might be simpler/cheaper all round

That would be the way I would go.

 

[[70521]]

Looks like I owe an apology to Jack. Sorry Jack I misread your post. Good luck with the EPQ and what are you planning to do post A Level?

 

[Spirit (of Glenans)]

Not unless they want to use the receiver for collision avoidance onboard, the utility of which would be questionable if I am correctly understanding what is meant by "keelboat": ie sailing boat with a keel rather than centreboard but not necessarily any accommodation, used largely for inshore daysailing. If the objective is simply broadcasting AIS data, receiving it elsewhere and plotting it on a website the AIS unit, GPS, antenna, coax and power is all that's needed. And per previous post you don't even need the AIS unit if you do it over mobile rather than VHF

We were typing simultaneously. Any other application of AIS, apart from the conventional arrangement, in a boat, hadn't occurred to me until I saw your post.

 

[Jack Hales]

Step 1 is to define what you want to achieve. AIS is not necessarily the best option if you just want to embed a tracker on your website. For AIS you'd need to install an antenna, GPS receiver and enough power to power the unit. You'd need an additional AIS receiver (onshore?) to receive and decode the signal unless you want to rely on the signal being picked up by hobbyists and relayed to an aggregation site like marinetraffic (which you'd then have to interface with to extract tracking data). You've also got a fairly valuable lump of equipment on each of your keelboats which may present security issues on a keelboat (if I understand the term "keelboat" correctly in this context).

For simply tracking, you don't need to be broadcasting your GPS data over VHF: you could dispense with the VHF part entirely and connect a GPS unit to a GSM board and send your GPS data directly over mobile Internet or via sms. Or buy a commercial GPS tracker unit. *Much* easier to install, much lower power (so you don't need massive batteries), much cheaper and small enough to conceal better. Moreover *IF* you need data in AIS format, it's then a straightforward programming exercise to convert GPS data on a receiving computer into AIS data:
AIVDM/AIVDO protocol decoding

If AIS (over VHF) is an end in its own right for pedagogical reasons, do obviously be aware of the differences between classes, including the new SOTDMA class B. Digital Yacht have a short and accessible paper on this:
https://digitalyacht.net/wp-content/uploads/2018/11/Class-B-SOTDMA-AIS-White-Paper-V1_01.pdf
I'm guessing you won't have reason to need anything more than the cheapest old style CSTDMA class B.

If you really do want to go with AIS, look for something at the cheap end of the spectrum, look at the power consumption, work out what size of battery would power it and for how long, look whether it's waterproof, think about where you'd install it and how you'd stop someone nicking it if it can't be locked away.

But a little GPS tracker sending data over mobile Internet which can be easily plotted on a website or (if necessary) assembled into AIS data on a receiving computer might be simpler/cheaper all round

Hello Iaika. Thank you for your long and detailed post. I wasn’t aware of options other than AIS, so thank you for raising this. I’ll now begin to look into small GPS trackers over AIS as that seems to be a much better option, as all I need to do is have the paths we’ve sailed appear on a map on the website. Adding SOG and heading may also be useful to have. I assume SOG is possible using GPS, but is heading? Do you have any suggestions for starters? Thanks a lot

 

[Jack Hales]

The Digital Yacht range seem to be the most popular. I don't know whether this is based on functionality or price.
I'm sure you know that these devices come as a 'black box' which must be connected up to a chartplotter and other devices, thus you will also have to investigate this aspect, e.g NMEA connectivity protocols etc.

I think I’ll be heading down Iaika‘s idea of just a GPS tracker now, as that’s sufficient for my needs I believe. Thanks

 

[Jack Hales]

Hello and Welcome Jack

As a grumpy old engineer I'd like to understand what you mean by "Transponder Options?"

As you state the school has keelboats, that covers a big selection of vessels. Can do define the area that the vessels will be sailing in.

Fundamentally, all Class B transponders have three basic options:

1. Off
2. On - Receiving only
3. On - Transmitting and receiving

Some may integrate with a compatible VHF DSC radio and that is about it.

Good luck with your son's EPQ, What does he plan to do following his A Levels?

Hi Sandy. As others have stated, I’m the one doing my EPQ and A-Levels. I’m not entirely sure what I’ll do after them, but I’m looking towards a career path in game design / computer science - not sure yet. But my EPQ can’t overlap with my studies, hence this topic choice, since I’ve been sailing with the school for the past couple of years and I’ve fallen in love with it, even picked up some silverware with them ?

Anyway, I’m just looking at having a tracker on the boat that plots the paths we take on a map to the school website live, with maybe other data such as SOG and heading. I had assumed AIS was the only way to go, hence my initial post, but Iaika kindly informed me that just a small GPS tracker would do the job just fine; for much less and easier installation.

The school’s keelboats are modified Etchells 22s that will be sailing around the Solent and RTI races.

Thanks

 

[Jack Hales]

Looks like I owe an apology to Jack. Sorry Jack I misread your post. Good luck with the EPQ and what are you planning to do post A Level?

Thanks. And see my other post

 

[RichardS]

Hi all,

I’m new to the forums, and I’ve joined as I think some people on here may be able to help me with something. I’m currently doing my A-Levels and one of those is an Extended Project Qualification (EPQ). My plan for this is to investigate and research different AIS Transponder options for the school’s keelboats, and then ultimately install the chosen option and embed a map / tracker onto the school’s website.

From my preliminary research, I need to look for AIS Class B transponders. I’ve found a few online, all with varying prices and I’m not sure what would be best. On top of that, I can’t find many reviews of products either. I thought that there would be some people on this forum who have some experience in this field, so if you have any tips / suggestions for AIS Class B transponders, what to look for, what to avoid, that would be greatly appreciated.

Thanks a lot, Jack

If you are wanting to research AIS transponders (actually called receivers or transceivers) in general rather than specifically for map tracking, then look at the transponders which transmit their data by wifi as well as cable (NMEA). Everything is going wifi / bluetooth these days and I find that having the remote data connectivity is invaluable.

The most respected specialist name in AIS/wifi is probably Vesper Marine but their products are definitely not the cheapest.

Richard

 

[ashtead]

Hi Jack
A neat solution would be if you could find a sponsor to help fund your devices ? Maybe in return for some stickers on the Etchells someone like Digital yacht would help with a solution ? Looks to me be educational it would be a charitable donation for a suitable corporate and lots of scope for utube opportunities in terms of advertising with you sailing in Solent.

 

[Pirx]

Jack, As it happens I have a bit of experience of managing IT projects, and one thing I discovered is that it helps to start with a list of all the ducks in the pond before starting to get them in a row.

It would be useful to know:

The boats:
Where are these keelboats? What sort of boats are they? How many of them do you want to track? What sort of sailing do they do? Do they have engines? or batteries? How long will they be away from shore facilities? Where could you mount an aerial ? Is there a watertight locker?

Then for your tracker:
What do you want to do? Just know where the boats are ? Include data on speed, course? Just create pertty pictures on the website ? Do the boats need to display data from each other?

The project:
Just you or is there help? Are there any programming skills? Hardware skills? Is there a budget for buying hardware ?

The EPQ:
Are you serious about actually installing hardware in boats? or is this going to be a paper exercise?

AIS may not be the way to go for the reasons mentioned in previous posts. You might like to have a look at: Particle IOT - they will sell you a very inexpensive, low power, easy to program processor that can communicate via the mobile 'phone system. They also sell a 'tracker' but it would be more fun to connect the processor to a GPS module and write your own software. There are many other options; I only mention Particle as I have some experience of using their kit.

 

[ashtead]

Prix -I think Jack has answered most of these questions in earlier posts given they are Etchells ?

 

[prv]

I assume SOG is possible using GPS, but is heading?

You'll get COG (provided the boat's moving) and SOG from the GPS, but if you want actual heading you'll need a compass. Doesn't have to be an expensive marine device, you should be able to get a sensor module for comfortably under a tenner which would connect directly to an Arduino. Or it wouldn't surprise me if someone was selling breakout boards with both GPS and compass sensors on them already.

Before going any further I guess we need to establish whether building the transmitters is in the scope of your project, or if you just want to buy something off the shelf and the main focus is in handling the data that comes in. Because there are quite a few GPS / GSM tracker devices out there already, but assembling one (most likely in the Arduino ecosystem, being the most accessible for beginners) is also not all that hard.

Pete