5 ms·

But with two cameras a system can see that the road sign is far away.

Retric 9y ago
If that worked well they would not need a radar system. Accurate binocular vision is a hard problem we make a lot of assumptions about how the world works. Again here is a sample image. http://iowahighwayends.net/ends/June06/16/34exit263_99_halfmi.jpg http://iowahighwayends.net/ends/June06/16/34exit263_99_halfm... Notice the road bleeds into the sign, but based on experience we assume the car is not about to hit the bridge at road height. It's a single image, so we are not using binocular vision to figure this out.
- nkkollaw 9y ago
  Those signs are 4 meters above ground level. You're saying that that can't/shouldn't be taken into consideration? They're not at all in front of any car...
  - Retric 9y ago
    But how can you tell they are 4 meters above the ground level. Nothing in the image directly shows the last row of signs are that high off the road. We can say they are not close enough to be a problem yet, but all I am pointing out is it's a harder problem than your thinking about with a lot of potential false positives.
    - nkkollaw 9y ago
      I am not talking about images, and I never have. I'm talking about maps + GPS (where is the road? will it curve in 50 meters?), and radar (what's in front of the car? how far is it? is it in the middle of the street, or on the side? Is it at the same height as my car?). I don't see how these two tools together can make accellerating towards a stationary object in front of you make more sense than slowing down, or at least make some sort of sound to alert/wake up the driver. Like I said, I know it's a difficult problems and very smart people have been working on this for possibly 20 years, but it still doesn't make sense to me.
      - Retric 9y ago
        You're bringing up maps, but they don't help in this case. Consider what happens if one of those signs falls down. You need to react to what the sensors detect not what it assumes is going on. (Maps useless) Radar shows relative speeds, but can't distinguish between the road, bridge, and a stationary firetruck. It simply does not in any way help with this problem. (Radar useless) LIDAR does what your thinking of, but Tesla does not use it. (LIDAR missing) They use images, to avoid using LIDAR. So, now we have to detect stuff from images which is why I am showing you images. (immages only thing you have.)
        nkkollaw 9y ago
        Radar only works for moving objects?
        Retric 9y ago
        At highway speeds and significant range yea. This gets into signal processing, when you send out a radar pulse you get a lot of junk returns. If you are slowly backing up and just want to know if a wall is there sure that works fine. But, for more distant objects a single pulse gives ever more crap the further out it travels. If you send 2 pulses next to each other you can adjust for vector of car and ignore the repeated data to just look for stuff moving relative to the background. This results in really 'easy' automatic cruse control that ends up hitting stopped objects on the road. PS: Things would get a little better if cars had one of those rotating arrays you see on ships, but car radar is a solid state system.
- ec109685 9y ago
  It is going to have to work well for their autonomous system to actually work over time. Yes, it is a hard problem, but not insurmountable (especially when they have data from thousands of cars driving the same roads). Also, they want to deliver value today, even before they can use most of their camera feeds, so state of the art today hopefully won’t be state of the art a few years from now: https://forums.tesla.com/forum/forums/how-many-cameras-are-currently-use-my-ap2-car https://forums.tesla.com/forum/forums/how-many-cameras-are-c...

If that worked well they would not need a radar system. Accurate binocular vision is a hard problem we make a lot of assumptions about how the world works. Again here is a sample image. http://iowahighwayends.net/ends/June06/16/34exit263_99_halfmi.jpg http://iowahighwayends.net/ends/June06/16/34exit263_99_halfm... Notice the road bleeds into the sign, but based on experience we assume the car is not about to hit the bridge at road height. It's a single image, so we are not using binocular vision to figure this out.

nkkollaw 9y ago
Those signs are 4 meters above ground level. You're saying that that can't/shouldn't be taken into consideration? They're not at all in front of any car...
- Retric 9y ago
  But how can you tell they are 4 meters above the ground level. Nothing in the image directly shows the last row of signs are that high off the road. We can say they are not close enough to be a problem yet, but all I am pointing out is it's a harder problem than your thinking about with a lot of potential false positives.
  - nkkollaw 9y ago
    I am not talking about images, and I never have. I'm talking about maps + GPS (where is the road? will it curve in 50 meters?), and radar (what's in front of the car? how far is it? is it in the middle of the street, or on the side? Is it at the same height as my car?). I don't see how these two tools together can make accellerating towards a stationary object in front of you make more sense than slowing down, or at least make some sort of sound to alert/wake up the driver. Like I said, I know it's a difficult problems and very smart people have been working on this for possibly 20 years, but it still doesn't make sense to me.
    - Retric 9y ago
      You're bringing up maps, but they don't help in this case. Consider what happens if one of those signs falls down. You need to react to what the sensors detect not what it assumes is going on. (Maps useless) Radar shows relative speeds, but can't distinguish between the road, bridge, and a stationary firetruck. It simply does not in any way help with this problem. (Radar useless) LIDAR does what your thinking of, but Tesla does not use it. (LIDAR missing) They use images, to avoid using LIDAR. So, now we have to detect stuff from images which is why I am showing you images. (immages only thing you have.)
      - nkkollaw 9y ago
        Radar only works for moving objects?
        Retric 9y ago
        At highway speeds and significant range yea. This gets into signal processing, when you send out a radar pulse you get a lot of junk returns. If you are slowly backing up and just want to know if a wall is there sure that works fine. But, for more distant objects a single pulse gives ever more crap the further out it travels. If you send 2 pulses next to each other you can adjust for vector of car and ignore the repeated data to just look for stuff moving relative to the background. This results in really 'easy' automatic cruse control that ends up hitting stopped objects on the road. PS: Things would get a little better if cars had one of those rotating arrays you see on ships, but car radar is a solid state system.
ec109685 9y ago
It is going to have to work well for their autonomous system to actually work over time. Yes, it is a hard problem, but not insurmountable (especially when they have data from thousands of cars driving the same roads). Also, they want to deliver value today, even before they can use most of their camera feeds, so state of the art today hopefully won’t be state of the art a few years from now: https://forums.tesla.com/forum/forums/how-many-cameras-are-currently-use-my-ap2-car https://forums.tesla.com/forum/forums/how-many-cameras-are-c...