[HN Gopher] Heat-assisted detection and ranging
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Heat-assisted detection and ranging
Author : bookofjoe
Score : 45 points
Date : 2023-08-04 19:24 UTC (3 hours ago)
(HTM) web link (www.nature.com)
(TXT) w3m dump (www.nature.com)
| wpietri wrote:
| I am very disappointed that unlike radar, lidar, and sonar, this
| "HADAR" technology is not an active-sensing technology, but just
| relies on passive IR emissions. I was imagining a car driving
| around with a big open flame at the front like something out of
| Mad Max.
| dylan604 wrote:
| Somebody is prepping for Burning Man I take it
| wpietri wrote:
| All I'm saying is that if we're going to have killer robot
| cars roaming the streets and interfering with firefighters
| [1], we might as well do it properly.
|
| [1] https://www.theguardian.com/us-news/2023/jun/23/self-
| driving...
| dylan604 wrote:
| Interfering with firefighters is a bit different from
| driving around and starting fires though, init?
| dharmab wrote:
| IR floodlights mounted to the front of trucks is a thing.
| Here's an example with photos of infrared lights used on a
| smuggling vehicle so the driver could turn the headlights off
| and drive by night vision: https://youtu.be/a8Q9Yibblbc?t=626
| Arrath wrote:
| Sounds similar to IRST (Infrared Search & Track) as used in
| combat aircraft.
| MayeulC wrote:
| I don't have access, what's the gist? Heat emission then timing
| combined with thermal imaging? AFAIK, most *AR methods are active
| and rely on timing, but the abstract mentions passive detection.
| jcims wrote:
| I can't tell what they are doing. It seems like it's merging
| visible and thermal imaging to improve segmentation and
| identification, then looking up the identified objects for
| ranging. No?
|
| The thermal images in their examples seem to be intentionally
| using a wide temperature gamut to reduce the contrast in the
| image (and make it look bad). Most thermal imaging solutions will
| automatically adjust and give you a much better result.
|
| Regardless I can see lots of benefits of integrating the two as
| basically another color channel. There's a _lot_ of information
| available.
| Roguelazer wrote:
| "Our work leads to a disruptive technology that can accelerate
| the Fourth Industrial Revolution (Industry 4.0) with HADAR-based
| autonomous navigation and human-robot social interactions."
|
| Really, though?
| cs702 wrote:
| Jeez... that reads like poorly written PR.
|
| It doesn't belong in academic work, no matter how impressive
| the authors think it may be.
| jonathankoren wrote:
| These industrial revolutions are coming faster and faster, and
| somehow feel less transformative with each unveiling. I only
| know arguably two. I have no idea what the third, let alone the
| fourth was.
| mcpackieh wrote:
| Industrial, chemical, and information.
| ben_w wrote:
| First: powered tools, mechanised factories, basic but modern
| chemical processes.
|
| Second: mass production, interchangeable parts, reliable
| steel, telegraph and other basic uses of electricity.
|
| Third: computers and everything related to them.
|
| Fourth: all the buzzwords and not much substantial at this
| time -- though when the dust settles, I won't be surprised if
| at least _a few_ currently popular things are still seen as
| relevant and not merely flash-in-the-pan cultural artefacts
| like the 18th Amendment, patent medicine, or Spiritualism.
| nine_k wrote:
| Most IR cameras work with IR as heat emission. They are useful in
| the dark, without revealing the camera.
|
| Most optical cameras work with reflected light, not direct
| emission. The source of light is usually away and at an angle;
| this allows for shadows, textures, etc.
|
| I don't see why an IR camera can't work the same way as an
| optical camera, if reflected IR is used; IR photos under e.g.
| sunlight look fine enough.
|
| Radars or lidars work with their own scanning sources of
| illumination: microwave, IR, or optical. I wonder if the HADAR
| uses its own source of IR; if it does, how different it from a
| LIDAR?
|
| (All these mysteries can be solved for $29, but I'm not yet
| curious enough.)
| edrxty wrote:
| As a note, try to avoid using IR to describe LWIR, there are
| many IR sub bands (NIR, SWIR, MWIR, LWIR) and your phone camera
| can detect at least one of them.
| _trampeltier wrote:
| All IR cameras catch also reflected IR. Thats why you have to
| know the emissivity to calculate the true temperature.
| edrxty wrote:
| Yeah go play with an LWIR camera of you really want to
| understand the spectrum. For instance, everything becomes a
| mirror, you can see yourself standing in front of surfaces
| that have better than ~5um surface finish (quite rough sheet
| metal and such) and clouds appear hot-ish because while they
| are themselves quite cold, they're reflecting LWIR from the
| ground, hence why overcast nights are much warmer.
| malaya_zemlya wrote:
| https://hal.cse.msu.edu/assets/pdfs/papers/2023-nature-heat-...
| nine_k wrote:
| Thanks! This clarifies _a lot._
|
| - They use and combine both optical and LWIR data.
|
| - They are able to split the IR signal into emissive and
| reflected, and thus measure the temperature.
|
| - Using the spectral information + some ML models, they are
| able to identify materials, and paint / augment pictures
| using this information.
|
| That's actually impressive.
| mkoryak wrote:
| For some pictures
|
| https://github.com/FanglinBao/HADAR
|
| and videos
|
| https://purdue0-my.sharepoint.com/personal/baof_purdue_edu/_...
| Animats wrote:
| Behind Microsoft paywall.
| cududa wrote:
| What? I'm not even logged in and can see it. Are you under
| the impression you need to pay for a GitHub account to view
| things hosted on it?
| robertlagrant wrote:
| You don't think they're talking about the sharepoint.com
| URL?
| [deleted]
| visviva wrote:
| To me, "ranging" means measuring the range to the target
| directly, not estimating it from other measurement types
| (bearings, for example). Can someone explain if that's what the
| authors are doing here? Is it analogous to stadiametric ranging?
| I haven't read through this in depth, but I can't figure out what
| their method is.
| edrxty wrote:
| Just because nobody made me sign an NDA for this: there are
| satellite companies using this for finding other satellites in
| eclipse. It's a pretty brilliant strategy if you want to dock
| with something and there's no usable visible light. You can make
| markings that appear clearly in LWIR by making dark parts shiny
| (see mostly empty space reflected) and light parts matte (see the
| thermal emissions of the spacecraft)
| visviva wrote:
| This is a common approach - besides being robust to lighting
| conditions, it's less sensitive to glinting.
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