I've heard bats are almost blind but they fly around using some type of signals in order to know where the objects are around them
Bats slam into buildings because they can't 'see' them
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Re: Bats slam into buildings because they can't 'see' them
#12Poor bats. They also get their lungs exploded by the pressure differences created near wind turbines: https://www.wind-watch.org/news/2016/09/27/wind-turbines-are...
Re: Bats slam into buildings because they can't 'see' them
#13Earlier quoted context omitted.
Vision based on visible light doesn't suffer from the problem in the same way as echolocation or lidar, since it is not dependant on observing signals emitted by the observer. I guess very smooth surfaces might act as mirrors, which will probably bring it's own set of difficulties for machines. Anecdotally, I can say my own stereo vision doesn't have big difficulties with most smooth surfaces though :)
But bats also use vision based on visible light. I haven't read the article yet, but do they explain about why the bat wouldn't see the building with its eyes?
"researchers can rule out the possibility that the bats were visually confused, because the experiments were done under infrared light, which bats can't see, and so they would have been relying entirely on echolocation."
Re: Bats slam into buildings because they can't 'see' them
#14I had read this as Bots slamming into buildings, and was looking for a discussion of lidar and stereo vision systems. But won't lidar have the same issue, with a clean glass surface? Similar with stereo vision - if there are no features at the surface to correlate.
Vision based on visible light doesn't suffer from the problem in the same way as echolocation or lidar, since it is not dependant on observing signals emitted by the observer. I guess very smooth surfaces might act as mirrors, which will probably bring it's own set of difficulties for machines. Anecdotally, I can say my own stereo vision doesn't have big difficulties with most smooth surfaces though :)
I know I have slammed into transparent surfaces because I couldn't see them.
It probably gets worse the higher you go, because there is less grassy people adding marks to them, and less "people are hitting this too much, we'd better reduce that glass size". Birds are famous for getting them wrong.
Re: Bats slam into buildings because they can't 'see' them
#15Poor bats. They also get their lungs exploded by the pressure differences created near wind turbines: https://www.wind-watch.org/news/2016/09/27/wind-turbines-are...
Meh, a 5 Mega Watt wind turbine kills less wildlife than the average outdoor cat.
Re: Bats slam into buildings because they can't 'see' them
#16That made me wonder how bats see water surfaces. Though I suppose not seeing them is less of a problem since they're not vertical :P
This is a good point. Perhaps the sound penetrates a distance into the water and you get scattering, returning a small signal.
Re: Bats slam into buildings because they can't 'see' them
#17Poor bats. They also get their lungs exploded by the pressure differences created near wind turbines: https://www.wind-watch.org/news/2016/09/27/wind-turbines-are...
Meh, a 5 Mega Watt wind turbine kills less wildlife than the average outdoor cat.
> "Meh, a 5 Mega Watt wind turbine kills less wildlife than the average outdoor cat."
Do you have some sort of data to back this up?
Re: Bats slam into buildings because they can't 'see' them
#18I had read this as Bots slamming into buildings, and was looking for a discussion of lidar and stereo vision systems. But won't lidar have the same issue, with a clean glass surface? Similar with stereo vision - if there are no features at the surface to correlate.
Yes, lidar bounces off surfaces at shallow angles to give false readings. Also, the long wavelength of IR means that lots of flattish surfaces are good mirrors. In mobile robotics, glass panelled corridors are perceived very badly.[1]
Passive depth from stereo usually has big holes where no features are detected[2]. That's why Kinect and the like project their own IR texture into the scene. Outdoors ambient IR overwhelms the projection unless you use powerful lasers.
The upshot of this is that robots are vulnerable to banging into stuff, like bats.
[1] I don't know for sure but it's likely that the right hand side of this map I found online has glass walls causing bad range data: https://i.pinimg.com/originals/e0/87/04/e08704b6dc925b575c2f...
[2] If it doesn't, it's because the holes have been filled by interpolation - guessing what is there rather than observing it directly.
Re: Bats slam into buildings because they can't 'see' them
#19That made me wonder how bats see water surfaces. Though I suppose not seeing them is less of a problem since they're not vertical :P
Real life water surfaces are probably not as smooth as glass windows. Just a guess.
Re: Bats slam into buildings because they can't 'see' them
#20Earlier quoted context omitted.
Meh, a 5 Mega Watt wind turbine kills less wildlife than the average outdoor cat.
> "Meh, a 5 Mega Watt wind turbine kills less wildlife than the average outdoor cat." Do you have some sort of data to back this up?
I imagine that Retric (https://news.ycombinator.com/item?id=15228800)
is referring to stories like https://www.washingtonpost.com/national/health-science/outdo... and https://www.nytimes.com/2014/03/22/opinion/sunday/the-evil-o... (DDG results for "outdoor cats wildlife death"), compared to, say, http://www.smithsonianmag.com/smart-news/how-many-birds-do-w... (DDG result for "wind turbine wildlife death").
This is likely unpopular (especially with cat people like me), but I'm not sure what's callous about it—unless you mean the "meh" part, in which case I'm not sure how backing it up with data makes it any less callous.