[POTM] dAISy - A Simple AIS Receiver

[chicken 630]

I haven't tried any other modules, but I think the one above is about as easy as it gets.

 

I have a very cheap Hope-RF module on my bench that claims to be compatible with Si446x. But patching it up was a mess as there's a lot less space. And lack of 100 mil headers make for more work to break it out. Still have to wire it to a Launchpad to test.

 

But don't hold your breath. The weather is way to nice to spend time in the lab right now

[enjoylife 0]

Your module looks fantastic! I have bought a similar one from Radargadgets: http://www.radargadgets.com/

But doesn't show very good performance. It can only see 15 boats while the other standard AIS class A receiver can get 40!   

I love this module and looking forward to buying one for play. 

[gmtii 11]

hi,

 

dAISy USB has a solid and excellent sensitivity ...with a simple 1$ DIY electrical wire copper dipole it can receive ships exceeding 553 nm. - 1000 km !!!!

 

 

Esteban.

 

[PaulTech 2]

I managed to buy modules that weren't in 2.54mm DIP config , actually 1.27mm SIL but didn't want bits of wire everywhere. I rummaged thru my boxes and found the perfect solution, 24 pin SOP adaptor boards. The pic is BEFORE soldering, looks great after soldering.

http://bit.ly/1p3sdEN

[chicken 630]

@@PaulTech good thinking

 

Btw, the image does not show for me. You can easily include images in a post by attaching them (via "More Reply Options").

[PaulTech 2]

Had to take a photo of the back as well as it had the pin desigations

[PaulTech 2]

I used the whole adaptor for each board as I had plenty and they are cheap in bulk but it should be possible to cut each in half and make two adaptors. I like the whole board as it provides more support and makes them easy to handle. Of course, if the board is too small to fit on the intact adaptor than bisection would definately be necessary.

[Lgbeno 189]

It would be really cool to see this data get pushed to data.sparkfun.com we could do some cool web interface on imp.guru. Here is a example of tracking adsb data for airplanes in Honolulu http://imp.guru/f1n

[cowlum 1]

Hi Everyone

 

This really is a great project.

I'd quite happily purchase this.

 

 

As an offshoot to this, what I'd like to see on the market is a small deivce I could plug dAISy into that alarms on detection of a signal.

i.e. a device that powers dAISy from the house batteries and is itself an audio alarm alerting signal detection.

This way I could leave it running 24/7, when a ship arrives on the horizon an alarm triggers, I power up my chart plotter, removing dAISy from the alarm/power supply and plugging it into the chart plotter.

The purpose being to save power, which is very precious in small sailboats.

 

Presumably dAISy and a powersupply/alarm would consume very little power in comparison to dAISy and a chart plotter.

 

Thanks

[chicken 630]

Thanks for checking out my little project.

 

@@Lgbeno If going the IoT route, my first goal would be to submit messages to Marine Traffic or AISHub without a PC.

 

@@cowlum Interesting idea. If it's just about detection of something in range, one could easily change the software to turn on a pin when a message was received within the last 15 minutes or so. However, I'm not sure how useful that alone is. For a more intelligent warning system, dAISy would need to interpret the messages it receives. This way it can determine whether the message is from a ship or a base station, how far away the object is and what direction it moves (would require a GPS module).

 

There are lots of possibilities when processing AIS messages in an embedded device. That's why I consider to build the complete receiver (i.e. what today is dAISy USB) in a BoosterPack or Shield form factor. Combined with an Energia/Arduino library that spits out the decoded data it would be pretty straight forward to hack together these kind of projects.

[cowlum 1]

I completely agree that detection alone is not very usefull (or fun).. and im not suggesting detection alone is what we want.

 

Many small sailboats (your target market) only have 100-200ah charged by solar to run everythnig onboard, so running a chart plotter long periods (when its actually needed) is not an option. Most sailboats I go on dont bother with chartplotter AIS because in the harbour races keeping watch for 4-8 hours is easy. When sailing longer offshore races we get tired but the boat cant afford the energy to run a common ais chart plotter long periods. So we go without.

 

It would be great if there was a device that used little power on alert mode and then fed nmea to the power hungry chart plotter.

 

I guess my comment was more about a hole in the market than anything else..

[chicken 630]

@@cowlum What criteria would you use for an alarm? Anything within reception (~5 nautical miles with a basic antenna at sea level)? Or something more specific?

 

What would you use as alarm? Piezo speaker?

 

And what is an acceptable power consumption? In its current form it draws a bit less than 20mA.

[abecedarian 330]

I don't know the feasibility of it, but on ebay there are little micro wind power generators that output 0.01 - 15v, .2A max current. Seems ideal for a sailboat?

[cowlum 1]

How much power would be acceptable? As little as possble...

A better way to answer this question is to show you the competition.

 

1)VHF unit AIS (requires additional gps to work) in receive mode ~0.8A  (~$300)

 

2)AIS receiver + chart plotter ~0.4A  (~400+)

 

3)AIS receiver + Laptop  ~LargeA  (price really varies, I have a discriminator bypass on an old VHF)

 

**Laptops are ultimately too delicate for reliable navigation at sea.

 

All options are power hungry and overkill for the usual coastal passages on small vessels.

 

You could alarm on detection of signal, Aerial and location being the determining factor. 2-5nm would be about right.

If you wanted to intergrate gps and add a level of intellegnce that may be benificial.

Or possbily strength of signal determins volume of alarm?

 

I really had not thought much further than a small box that supplies power to daisy and sets off a peizo if a ship approaches. Power saving being the name of the game.

 

If its cheap enough and works well enough, I'd purchase it.

[cowlum 1]

@@abecedarian Wind generators and solar panels work reasonably well on sailboats. But most race boats dont want the weight or wind drag and you cant always rely on the wind and/or sunny days.

 

Also, Even if you had the perfect conditions to claim and store the 0.2A you are not competing with the loss from most Nav systems.