AIS Closest Point of Approach warning

[Paul Elliott]

It's pretty nice to see my boat in your demo! (We captured those AIS files aboard VALIS.)

As for color coding, I suggest that you run your color choices by someone with red-green color deficiency. I have it, and it's quite common in men. We can usually tell the difference, but when the colors are small or dim it gets quite hard. It also affects our perception of other colors, so what looks obvious to you may be quite subtle to others. "Subtle" is not what you want.

[damianham]

Originally Posted by Paul Elliott

It's pretty nice to see my boat in your demo! (We captured those AIS files aboard VALIS.)

As for color coding, I suggest that you run your color choices by someone with red-green color deficiency. I have it, and it's quite common in men. We can usually tell the difference, but when the colors are small or dim it gets quite hard. It also affects our perception of other colors, so what looks obvious to you may be quite subtle to others. "Subtle" is not what you want.

Yeah there is not much difference in the colours of the map icons between the orange of the bow crossing and the yellow of a warning - although the difference is clear in the target list.
I could add an option to auto popup the info for a collision risk - would that be a good idea ?

[damianham]

Many thanks to everyone that contributed to this thread and helped me with the design of the AIS feature of SmartBox. I have made a video of the AIS feature in the product which you can view on the SmartBoatNetwork FaceBook group

https://www.facebook.com/groups/1996...?fref=mentions

If you could take a look any comments - especially criticism - would be most appreciated to make sure I am on the right track and not missing anything.

Also 1000 thanks to Paul Elliot for the AIS log file which made the development and testing so much easier.

[conachair]

Originally Posted by damianham

Also 1000 thanks to Paul Elliot for the AIS log file which made the development and testing so much easier.

I have a file with about 300,000 ais messages if it's any good to you?

Recorded with node-red on a raspberry pi.

[damianham]

Originally Posted by conachair

I have a file with about 300,000 ais messages if it's any good to you?

Recorded with node-red on a raspberry pi.

Yes the more data for testing the better, thanks.

[tanglewood]

Originally Posted by Dockhead

This issue drives me crazy with the AIS implementation on my plotters (B&G Zeus). I have to watch the bearing.

The best solution of this I've seen is the graphic display of the crossing geometry in OpenCPN. You can select vessels and turn it on and off. It's great and really helps you to make decisions -- an instant graphic view of what kind of situation you are dealing with.

I'm pretty sure your B&G can display relative motion vectors which will answer your question about how you will pass the other vessel.

[damianham]

Here is the context
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Originally Posted by meirriba

I have a related issue. The CPA shown by the system does not provide info if the other vessel is passing (at the CPA) in front or behind our vessel. This is an interesting info as it may help to decide how to react. Some systems have a relative bow vector that can be shown for the incoming vessel which provides visual answer to this. However, it would be nice if the CPA will be accompanied by a letter or +/- character to warn about the relative position of the impending CPA

Originally Posted by Dockhead

This issue drives me crazy with the AIS implementation on my plotters (B&G Zeus). I have to watch the bearing.

The best solution of this I've seen is the graphic display of the crossing geometry in OpenCPN. You can select vessels and turn it on and off. It's great and really helps you to make decisions -- an instant graphic view of what kind of situation you are dealing with.

Originally Posted by tanglewood

I'm pretty sure your B&G can display relative motion vectors which will answer your question about how you will pass the other vessel.

The solution I went with when you have an intersecting course with another vessel is to render vector lines from both vessels to the crossing point and the colour of the lines indicates whether it is a bow crossing (orange) or stern crossing (light blue). You can also elect to see the time difference between each vessel reaching the crossing point instead of the TCPA in the threat list entry.