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This is the reason why an autonomous car should have radar/lidar. With those sensors such a scenario would be extremely easy to detect.
by constantcrying 2y ago
This is the reason why an autonomous car should have radar/lidar. With those sensors such a scenario would be extremely easy to detect.
- VMG 2y agoTo be fair, even the photo sensors should have been able to pick it up in this case
- bdcp 2y agoAt least pick up the CLOSED barrier.
- bell-cot 2y agoAt least for my elderly brain - in low-visibility conditions, the red flashing lights of an "active" railroad crossing signal are far more distinctive and attention-grabbing than the very thin, kinda-fog-colored gates.
- InCityDreams 2y agoI believe it to be more common in the EU to have dangly bits (metal fencing?) that hangs from the barrier to the floor. when the barrier lifts up they 'fold' vertical. This presents a proper barrier (that stops kids, cyclists, pedestrians from getting under the barrier when deployed), the 'struts' are painted red and white so they're very visible. *can't speak for absolutely everywhere, but my ride to work there are two sets of tracks I pass that have barriers that are designed to stop the stupid. Oh, I guess self-driving vehicles, too, now.
- IshKebab 2y agoI dunno if lidar would have helped here much since it was so foggy (unless fog is transparent to IR or something?). Radar would, but radar is also a bit crap - in particular angular resolution is very very poor.
- anonimonkey 2y agoFog (small water droplets suspended in air) is transparent to light but it can reflect it if the wavelength of light is smaller than the water droplet diameter. Since there are so many droplets it scatters light making lidar useless. The usual diameter of fog droplets is in the micrometer range, but is highly variable. So microwave/milimeterwave lidar could theoretically work.
- modeless 2y agoRadar would probably not, in this case. At the point where it crossed the road the train was not moving toward or away from the car, so radar would have to filter it out as a stationary object (stationary objects have to be aggressively filtered with radar to avoid false positives from metal signs or stopped cars near the road). Even if it somehow was detected as a moving object, sometimes trains stop in crossings, at which point it would definitely be a stationary object and radar would be useless.
- soco 2y agoCorrect me if I'm wrong but one shouldn't crash their car into stationary objects either, right? Or I'm missing the point of your comment maybe?
- IshKebab 2y agoYou are correct. The point is radar in cars has really bad angular resolution so it can't distinguish stuff that's directly in front of you (like a stopped train on a crossing) from stuff that's just to the side (like signs). Since both signals appear identical to the radar, and you don't want your car to emergency brake every time you go past a sign, cars filter basically ignore stationary objects detected by radar. That isn't what you want, but it's a limit of current commercially viable radar technology.
- dzhiurgis 2y agoA better rail crossing design would have helped. At such fog even human will miss this. Put a barrier further away, brighter lights, etc.
- belter 2y agoLidar can't handle fog or snow. It's a research area for improvements: https://www.cts.umn.edu/news/2023/april/lidar https://www.cts.umn.edu/news/2023/april/lidar
- krapht 2y agoHumans can't handle fog or snow either.
- penjelly 2y agowatch the video, a person can easily see the train, gate and lights before they disengage. Also a person would have heard the crossing noises, and the train horn.