

What can be seen using an IR camera on the ocean - joshandrews
http://ubcsailbot.org/2014/12/28/using-ir-imaging-to-detect-floating-obstacles/

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jzwinck
There are racing teams with multi-million dollar budgets who would be
interested in this sort of detection technology. For example, just a couple
days ago one of the top competitors in the Sydney-Hobart abandoned the yacht
race due to hull damage from hitting...something [1].

However, testing in waves is very important, and this article shows none of
that (barely mentions it, in fact). But at least the big boats have the
advantage of being able to put a sensor 50 meters up in the air, if that
helps.

[1] [http://www.smh.com.au/sport/sailing/sydney-to-hobart-
comanch...](http://www.smh.com.au/sport/sailing/sydney-to-hobart-comanche-and-
wild-oats-xi-lead-depleted-fleet-as-perpetual-loyal-retires-with-hull-
damage-20141227-12e8vb.html)

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jonah
I'd think underwater hazard detection would be more relevant.

Another modern shipwreck: [http://www.newyorker.com/news/sporting-
scene/twenty-first-ce...](http://www.newyorker.com/news/sporting-scene/twenty-
first-century-shipwreck)

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kristoffervh
Underwater hazard detection would be very interesting to explore, but for UBC
SailBot's purpose (crossing Atlantic Ocean with surface vessel) overwater
hazard detection seems more feasible with the technologies currently out there
(radar, IR, AIS, etc). Do you have any suggestions for good technologies to
explore for (horizontal) underwater obstacle detection? We have played with
the idea of horizontal sonar, but not sure how feasible this is...

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joshvm
It seems like you could take advantage of some background subtraction.

Detecting the horizon seems trivial enough (hough transform? or a robust edge
detector). If you know where that line is then you can take series of
gradients normal to it and form an average temperature model as a function of
distance from the horizon. If you take enough of these gradients across the
image, you should be able to get a robust average.

You then use this model to predict the temperature at each pixel and take a
difference with the observed data. What should happen is you get a ton of
~zeros, a bit of noise due to waves and any non-sea object will stick out like
a sore thumb.

The rule here is that absolute measurements will kill you when it comes to
dynamic range. You're much better off taking relative measurements.

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poopchute
Interestingly, the last picture there - the one looking at the sun - was taken
at a nude beach (wreck beach)

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kristoffervh
"clothing optional" you mean... ;-)

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mangoldm
Well that's kind of boring. I was hoping I could use this to look for sharks
before going for a swim.

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kristoffervh
now that would be awesome! :-D

