Getting AIS Details

[Land an]

Can anyone share exactly what you did to get AIS on the OpenCPN charts? I would like to learn the details on both receiving and transmitting AIS. What hardware, do dads did you buy and what settings on OpenCPN did you tweak.

[MarkJ]

Wacked the USB cable from the AIS into the computer and turned it on.

That was the difficult bit

[bcn]

Originally Posted by Land an

Can anyone share exactly what you did to get AIS on the OpenCPN charts? I would like to learn the details on both receiving and transmitting AIS. What hardware, do dads did you buy and what settings on OpenCPN did you tweak.

Receiving and transmitting AIS is done by the AIS Receiver(Rx) or Transponder (Rx/Tx) and these data are send to OpenCPN in NMEA0183 format.
OpenCPN does decode the data and renders those on the chart.
No settings to "tweak", and yes you will need some hardware to deal with AIS signals.
Have a look at the manual - OpenCPN User Manual | Official OpenCPN Homepage

[model 10]

For me , it was a right click for the real details. Like rudder angle of the target etc. etc.

[seandepagnier]

For me I use $8 digital tv receiver (r820t) and gnuradio.

[Land an]

Thanks guys. It's really just a plug and play? To receive AIS and transmit AIS?

So I just need the AIS equipment that has a USB connection? Since it will be displayed on my laptop running OpenCPN, I don't need AIS equipment that has a screen- or is there a reason to have that second AIS display also (besides just having a backup)?

Anyone want to suggest the AIS equipment for this job?

[model 10]

Looks like the ICOM unit sold by Sea Tech Systems is the best deal now. We have a different brand unit and it uses not the USB port but the serial port, I think.

[bcn]

We are using the em-trak B100 which has USB and serial. Very good performance.

And at home an em-trak R100 receiver. USB powered out of an Olimex A20 ARM system.

Hubert

[Neptune's Gear]

Actually there is more to it if you want to transmit. You need to (if you don't already) get a MMSI number from the country that the boat is registered in. It's not difficult, do a search on google for MMSI number and your country.

The physical connection , if to a PC can serial, USB, or Wifi.
There are many units available, from under $300 USD for receive only.

However, before you commit to something, consider this.
I recommend the Vesper Marine XB8000, if connecting to a PC, because;
It has all interface systems, NMEA0183, NMEA2000, WIFI, and USB.
It ALSO has multiplexing built in!! This means, what it "hears" on one port, it can repeat on another. For example, if your have older NMEA 0183 instruments, but NMEA 2000 Autopilot - the XB8000 will give you a seamless, bi directional connection for the two systems. It can also transmitt ALL the data received to up to 5 wireless devices (more if you add a wifi access point). So, you can have all your NMEA stuff on wifi connections to the laptop/smartphone/tablet (or all three) regardless of whether the source of the data is 0183 or 2000. This is a unique product, designed and made here in New Zealand.

If you want info on the Serial connections, have a look on my site HERE
AIS products listed HERE freight free to anywhere.
Cheers
Matt

[seandepagnier]

I don't recommend anyone purchase an expensive unit when they could just use this:

RTL2832U R820T DVB T USB Digital TV Tuner Receiver Support SDR F Laptop PC He | eBay

It receives from both channels at the same time because it has a 250khz wide bandwidth. This unit can also receive vhf audio channels if your main radio breaks (for weather or..) and also am/fm and with hacking can receive ssb as well. It can also turn your computer into a digital tv.

As far as multiplexing, you can run gpsd and it will repeat the signal as needed to any number of devices. I run hostapd on one machine, and all the computers (about 4 now all running opencpn) can have all the gps and ais data.

[bcn]

Originally Posted by boat_alexandra

It receives from both channels at the same time because it has a 250khz wide bandwidth. This unit can also receive vhf audio channels if your main radio breaks (for weather or..) and also am/fm and with hacking can receive ssb as well. It can also turn your computer into a digital tv.

Sean,

what antenna are you using?
Did you have an opportunity to compare with the standard AIS devices?

Hubert

[Neptune's Gear]

Sean, that is not a transponder, and does not convert NMEA2000 to or from NMEA0183, nor does it have WIFI. You are not comparing the same functions/features.
If all someone is looking for is a receiver, then that might be what some people wish to use.
This is a safety device, professional units are extensively tested and certified, at quite a cost. It is only reasonable that these devices cost more than something cobbled together with equipment not intended for this purpose.
It won't suit everyone..., but that's fine! :-)

[seandepagnier]

For a transponder you need something else, but a software radio option is theoretically possible.

This option is a receiver only, but it certainly works well. You can say my sculling oar is cobbled together from stuff I found in a dumpster, but yet I scull in and out of docks in places all over the world which are difficult to tack in. You can say this about my sailing rig for my kayak, made only from many scraps of fabric hand sewed together and bamboo, but I get on plane and have covered many miles in many places.

It can do wifi, I explained how already (run hostapd and gpsd on the computer with the dvb dongle)

I am using a standard vhf antenna from a vhf radio, I think it's about half a meter long.

As for nmea2000.. is there some reason why a small bit of software cannot convert nmea0183 into this format? If not, we must discourage anyone from using this format. Proprietary standards makes life difficult for everyone. Is there any enhancement to using this format? additional data? The standard messages are already completely adequate for plotting ships using opencpn.

[bcn]

Originally Posted by boat_alexandra

As for nmea2000.. is there some reason why a small bit of software cannot convert nmea0183 into this format? If not, we must discourage anyone from using this format. Proprietary standards makes life difficult for everyone. Is there any enhancement to using this format? additional data? The standard messages are already completely adequate for plotting ships using opencpn.

Sean,

NMEA0183 is not open neither - reverse engineered as well.
If you didn't already, have a look at https://github.com/canboat/canboat/wiki
This waits to be integrated into OpenCPN.

Integration of various modules is simpler with NMEA 2000. If you just want to listen a CAN transceiver is not expensive neither.
And more and more equipment will (only) have N2K in the future.
Different stuff if you want to send data into NMEA2000 (Autopilot for example). Then the protocol to register, address claim etc. would have to be implemented.

Hubert

[seandepagnier]

I think the issue is the fact that few people use CAN hardware with their laptops, and nmea2000 cannot work over serial.

This brings me to the next point... As developers, maybe it is time to think about defining our own open standard. nmea0183 doesn't have enough sentences for all of this, and also is rather inefficient using many bytes for what is sent. For nmea2000 it is a problem as well because we don't actually know what it can support or how to use it.

I have a 10DOF board on my raspberry pi, running autocalibration and sensor fusion algorithms to give me accurate boat motion attitude etc.. to drive my homemade autopilot. This data could be very useful for many applications, and can be used by various algorithms to learn about the boat's sailing characteristics in whatever sea states it is in. For these sensors I am big on redundant sensors for reliability but also for automatic calibration reasons and greatly reduced noise. Consider mounting accelerometers at different locations on the boat, including the top of the mast. These can over time remove non-linearities from other sensors like gyroscopes.

We also want to support things like radar, sonar data to map the bottom below and to detect debris like metal containers (I hit one 2 weeks ago slowly luckily) and tree logs, 3d ultrasonic anenometer data (from many anenometers mounted on various locations on the boat), Multiple gpses, mounted on different locations on the boat, sonar data to detect propellers from nearby vessels and whales. and possibly even digital camera data from underwater or cameras mounted on the mast panning the horizon, digital automatic gyro compensated sextants using image recognition to locate celestial bodies (as alternative to gps) or whatever etc... the list goes on and on, and obviously some of my ideas (but not all) are a bit far out for now.