14 ms·

I strongly believe LIDAR is the way to go and that Elon's vision-only move was extremely "short-sighted" (heheh). There are many reasons but that drives it home

• jillesvangurp 1y ago
  Lidar is great for object detection. But it's not great for interpreting the objects. It will stop you crashing into a traffic light. But it won't be able to tell the color of the light. It won't see the stripes on the road. It won't be able to tell signs apart. It won't enable AIs to make sense of the complex traffic situations. And those complex traffic situations are the main challenge for autonomous driving. Getting the AIs to do the right things before they get themselves into trouble is key. Lidar is not a silver bullet. It helps a little bit, but not a whole lot. It's great when the car has to respond quickly to get it out of a situation that it shouldn't have been in to begin with. Avoiding that requires seeing and understanding and planning accordingly.
  • deleted 1y ago
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  • HPsquared 1y ago
    It's an extra sensor you'd add into the mix, you'd still have cameras. Like the radar sensors. I think the reason Teslas don't have it, is because the sensor hardware was expensive a few years back. I assume they are much cheaper now.
    • ndsipa_pomu 1y ago
      Tesla have also backed themselves into a corner by declaring that older models are hardware capable of FSD, so they can't easily add LIDAR to new models without being liable for upgrading/refunding previously sold models.
      • b112 1y ago
        I thought they had it on some models already, then removed it on models after? edit: no, it was ultrasonic sensors. But this was likely object detection, and now it's gone.
      • gizajob 1y ago
        New for 2027 - ABSOLUTE Self Driving Pro Max!
  • michaelt 1y ago
    I think you might be under-estimating the importance of not hitting things. If you look at the statistics on fatal car accidents, 85%+ involve collisions with stationary objects or other road users. Nobody's suggesting getting rid of machine vision or ML - just that if you've got an ML+vision system that gets in 1 serious accident per 200,000 miles, adding LIDAR could improve that to 1 serious accident per 2,000,000 miles.
    • ModernMech 1y ago
      Because LIDAR can detect the object at the beginning of the perception pipeline, whereas camera can only detect the object after an expensive and time consuming ML inference process. By the time the camera even knows there's an object (if it does at all) the LIDAR would have had the car hitting its brakes. When you're traveling 60 MPH, milliseconds matter.
• zpeti 1y ago
  If a human brain can tell the difference between sun glare and an object, machine learning certainly can. It’s already better at X-rays and radiology in many cases. Everything you are talking about is just a matter of sufficient learning data and training.
  • audunw 1y ago
    1. A human has a lot more options to deal with things like sun glare. We can move our head, use shade, etc. And when it comes to certain aspects around dynamic range the human eyes are still better than cameras. And most of all, if we loose nearly all vision we are intelligent enough to simulate the behaviour of most objects around us to react safe for the next few seconds. 2. Human intelligence is much deeper than machine vision. We can predict a lot of things that machine visions have no hope to achieve without some kind of incredibly advanced multi-modal model which is probably many years out. The most important thing is that Tesla/Elon absolutely had no way to know, and no reason to believe (other than as a way to rationalise a dangerously risky bet) that machine vision would be able to solve all these issues in time to make good on their promise.
    • mcv 1y ago
      Not only do we have options to deal with it, we understand that it's a vision artefact, and not something real. We understand objects don't vanish or appear out of nowhere. We understand the glare isn't reality but is obstructing our view of reality. We immediately understand we're therefore dealing with incomplete information and compensate for that. Including looking for other ways to look around the instruction or fill in the gaps. Without even thinking about it, often.
  • deleted 1y ago
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  • jihadjihad 1y ago
    This comment is a perfect illustration of the hubris of this technology in general.
  • threatofrain 1y ago
• torginus 1y ago
  The mistakes you describe are the issues of the AI system controlling the car, not of the cameras themselves. If you were watching the camera feed and teleoperating the vehicle, no way you'd phantom brake at a sudden bit of glare.
  • nosianu 1y ago
    OP says nothing else??? > this tells me volumes about what's going on in the computer vision system Emphasis: > computer vision system
  • petee 1y ago
    Going from cameras to the human model, every morning on my way to work humans suddenly slam their brakes for the sun in their eyes: if you can't see, you can't see. I think it's another good example why cameras are not enough alone.
• moralestapia 1y ago
  >Elon's vision-only move was extremely "short-sighted" It wasn't Elon's but Karpathy's.
  • amelius 1y ago
    I suspect so too, but is it factual?
  • pinkmuffinere 1y ago
    For decisions of this scale (ie, tens of years of development time, committing multiple products to a single unproven technology), the CEO really should be involved. Maybe they’ll just decide to take the recommendation of the SMEs, but it’s hard for me to imagine Elon had no say in it.
  • Fricken 1y ago
    Sterling Anderson was the first autopilot director, and he was fired for insisting on Lidar. Elon sued Sterling Anderson, then hired the bootlick Karpathy to help him grease chumps.
    • mcv 1y ago
      But why is Elon so opposed to Lidar? I don't get it.
      • Fricken 1y ago
        At that time Lidar was too expensive and ugly to be putting in every car. Robust Lidar for SAE level 4 autonomous vehicles is still not cheap and still pretty ugly.
        • polishdude20 1y ago
          But that's what's needed. Tesla could have developed an effective and cheap lidar if they decided millions of their cars needed it.
• amelius 1y ago
  Your comparison to hallucination is spot on. LLMs have shown the general public how AI can be plain wrong and shouldn't be trusted for everything. Maybe this influences how they, and regulators, will think about self driving cars.
  • b112 1y ago
    Well I wish this was true. But loads of DEVs on here will claim LLMs are infallible. And the general public?! No way. Most are completely unaware of the foibles of LLMs.
    • BoiledCabbage 1y ago
      > Well I wish this was true. But loads of DEVs on here will claim LLMs are infallible. No the don't. You're making a straw man rather than trying to put forth an actual argument in support of your view. If you feel can't support your point, then don't try to make it.
      • greenchair 1y ago
        It's done in a roundabout way. Usually with a variation of "you had a bad experience because you are using the tool incorrectly, get good at prompting".
        • Eisenstein 1y ago
          That's a response to 'I don't get good results with LLMs and therefore conclude that getting good results with them is not possible'. I have never seen anyone claim that they make no mistakes if you prompt them correctly.
      • b112 1y ago
        A straw man? An actual argument? I responded to this parent comment: "LLMs have shown the general public how AI can be plain wrong and shouldn't be trusted for everything." You take issue with my response of: "loads of DEVs on here will claim LLMs are infallible" You're not really making sense. I'm not straw-manning anything, as I'm directly discussing the statement made. What exactly are you presuming I'm throwing a straw man over? It's entirely valid to say "there are loads of supposed experts that don't see this point, and you're expecting the general public to?". That's clearly my statement. You may disagree, but that doesn't make it a strawman. Nor does it make it a poorly phrased argument on my part. Do pay better attention please. And your entire last sentence is way over the line. We're not on reddit.
• CjHuber 1y ago
  Just imagine Tesla would have subventioned passive LIDAR on every car they ship to collect data. Wow that dataset would be crazy, and would even improve their vision models by having ground truth to train on. He’s such a moron
  • deleted 1y ago
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  • wombat-man 1y ago
    I think LIDAR was and maybe still is way more expensive. Initially running 75k. Now they're more around 10k which is better.
    • kibwen 1y ago
      This is off by orders of magnitude. BYD is buying LIDAR units for their cars for $140.
      • onlyrealcuzzo 1y ago
        That's likely closer to reality now, but that's not counting the cost for R&D to add it to the car, any additional costs that come with it besides the LIDAR hardware, plus the added cost to install it. All of that combined is probably closer to $1k than to $140. And, again, that's - what - 10 years after Tesla originally made the decision to go vision only. It wasn't a terrible idea at the time, but they should've pivoted at some point. They could've had a massive lead in data if they pivoted as late as 3 years ago, when the total cost would probably be under $2.5k, and that could've led to a positive feedback loop, cause they'd probably have a system better than Waymo by now. Instead, they've got a pile of garbage, and no path to improve it substantially.
        • terribleperson 1y ago
          I can't be sure, but I doubt Tesla is spending less than $140 on their cameras. High fidelity, high frame rate color cameras aren't actually cheap...
• chippiewill 1y ago
  As someone who worked in this space, you are absolutely right, but also kind of wrong - at least in my opinion. The cold hard truth is that LIDARs are a crutch, they're not strictly necessary. We know this because humans can drive without a LIDAR, however they are a super useful crutch. They give you super high positional accuracy (something that's not always easy to estimate in a vision-only system). Radars are also a super useful crutch because they give really good radial velocity. (Little anecdote, when we finally got the Radars working properly at work it made a massive difference to the ability for our car to follow other cars, ACC, in a comfortable way). Yes machine learning vision systems hallucinate, but so do humans. The trick for Tesla would be to get it good enough to where it hallucinates less than humans do (they're nowhere near yet - human's don't hallucinate very often). It's also worth adding that last I checked the state of the art for object detection is early fusion where you chuck the LIDAR and Radar point clouds into a neural net with the camera input so it's not like you'd necessarily have the classical methods guardrails with the Lidar anyway. Anyway, I don't think Tesla were wrong to not use LIDAR - they had good reasons to not go down that route. They were excessively expensive and the old style spinning LIDARs were not robust. You could not have sold them on a production car in 2018. Vision systems were improving a lot back then so the idea you could have a FSD on vision alone was plausible.
  • goalieca 1y ago
    > The cold hard truth is that LIDARs are a crutch, they're not strictly necessary. We know this because humans can drive without a LIDAR, however they are a super useful crutch. Crutch for what? AI does not have human intelligence yet and let’s stop pretending it does. There is no shame in that as the word crutch implies.
    • lazide 1y ago
      I think they meant crutch for the AI so they could pretend for investors that AGI is right around the corner haha
    • spot5010 1y ago
      I've never understood the argument against lidars (except cost, but even that you can argue can come down). If a sensor provides additional data, why not use it? Sure, humans can drive withot lidars, but why limit the AI to using human-like sensors? Why even call it a crutch? IMO It's an advantage over human sensors.
• gcanyon 1y ago
  The wiper system has nothing to do with self-driving -- it's based on total internal reflection in the glass: https://www.youtube.com/watch?v=TLm7Q92xMjQ https://www.youtube.com/watch?v=TLm7Q92xMjQ
  • sean_bright 1y ago
    Teslas do not use the rain sensors discussed in this video, they use cameras to detect rain.
    • gcanyon 1y ago
      Oh good lord, why? This is a solved problem, why would they waste their time on it. Wait, I think I know the answer: Elon's famous (at SpaceX) for saying the most reliable part is no part. So maybe this is a consequence of that. In any case, thanks, TIL!
  • vel0city 1y ago
    That's how every non-Tesla works. Tesla's don't do this method which is why their auto wipers have always been so bad compared to everyone else.
    • gcanyon 1y ago
      TIL, thx!
• UltraSane 1y ago
  Camera only might work better if you used regular digital cameras along with more advanced cameras like event based cameras that send pixels as soon as they change brightness and have microsecond latency and\or Single Photon Avalanche Diode (SPAD) sensors which can detect single photons. Having the same footage from all 3 of these would enable some fascinating training options. But Tesla didn't do this.
• jqpabc123 1y ago
  Engineering reliability is primarily achieved through redundancy. There is none with Musk's "vision only" approach. Vision can fail for a multitude of reasons --- sunlight, rain, darkness, bad road markers, even glare from a dirty windshield. And when it fails, there is no backup plan -- the car is effectively driving blind. Driving is a dynamic activity that involves a lot more than just vision. Safe automated driving can use all the help it can get.
  • Someone1234 1y ago
    I agree with everything you're saying; but even outside of Tesla, I'd just like to remind people that LIDAR as a complement to vision isn't at all straightforward. Sensor fusion adds real complexity in calibration, time sync, and modeling. Both LIDAR and vision have edge cases where they fail. So you ideally want both, but then the challenge is reconciling disagreements with calibrated, and probabilistic fusion. People seem to be under the mistaken impression that vision is dirty input and LIDAR is somehow clean, when in reality both are noisy inputs with different strengths and weaknesses. I guess my point is: Yes, 100% bring in LIDAR, I believe the future is LIDAR + vision. But when you do that, early iterations can regress significantly from vision-only until the fusion is tuned and calibration is tight, because you have to resolve contradictory data. Ultimately the payoff is higher robustness in exchange for more R&D and development workload (i.e. more cost). The same reason why Tesla needed vision-only to work (cost & timeline) is the same reason why vision+LIDAR is so challenging.
    • jqpabc123 1y ago
      The same reason why Tesla needed vision-only to work (cost & timeline) But vision only hasn't worked --- not as promised, not after a decade's worth of timeline. And it probably won't any time soon either --- for valid engineering reasons. Engineering 101 --- *needing* something to work doesn't make it possible or practical.
    • ethbr1 1y ago
      The primary benefit of multiple sensor fusion from a safety standpoint isn't an absolute decrease in errors. It's the ability to detect sensor disagreements at all. With single modality sensors, you have no way of truly detecting failures in that modality, other than hacks like time-series normalizing (aka expected scenarios). If multiple sensor modalities disagree, even without sensor fusion, you can at least assume something might be awry and drop into a maximum safety operation mode. But we'd think that the budget config of the Boeing 737 MAX would have taught us that tying safety critical systems to single sources of truth is a bad idea... (in that case, critical modality / single physical sensor)
• aaron695 1y ago
  [dead]
• qoez 1y ago
  Not sure it was actually Elon's move though, I heard it was mainly a decision taken by Andrej Karpathy
  • sheepscreek 1y ago
    That's an interesting take on this. Can you share the source?
  • trashface 1y ago
    Musk said it himself: https://www.youtube.com/watch?v=HmjuEikY4ew&t=502s https://www.youtube.com/watch?v=HmjuEikY4ew&t=502s (For those who don't want to click through "LIDAR is a fool's errand, and anyone relying on LIDAR is doomed."
• weinzierl 1y ago
  I think Elon's prediction was that LIDAR was too expensive and will stay too expensive. In a sense he was right, LIDAR prices did not drop and I wonder why that is?
  • yndoendo 1y ago
    Investments into re-engineering production to bring down cost is done when there is a market large enough for said product. True self-driving is still a baby that needs to grow and cannot even compete against an adult human with 30+ years of experience. As self driving actually forms to that level the market will grown.
    • fooblaster 1y ago
      Why do all of you think prices haven't come down? I can buy an AT128 from hesai for a few hundred dollars in volume. It's higher performance than any spinning lidar I could buy in 2017.
      • weinzierl 1y ago
        Elon's bet was one LIDAR against a bunch of cameras. A few hundred dollars is still way too much when you can get the cameras for a few tens.
        • Applejinx 1y ago
          In what universe is 'a few hundred dollars is way too much' for implementing full self-driving on an autonomous vehicle that moves like, and at the speeds of and in the spaces of, an automobile? A two to four ton vehicle that can accelerate like a Ferrari and go over 100 mph, fully self-driving, and 'a few hundred dollars is way too much'. Disagree. Even as they are dialing back the claims, which may or may not affect how people use the vehicles. These things respond too quickly for flaky senses based on human sensoriums.
      • yndoendo 1y ago
        You may have interpreted that and that is not what I said. Once a product starts to sell after initial design, time is take to reduce the development cost. Try to reuse parts or replace part A with B. A machine from early 2018 can be little different than ones going out the door late 2018. _Kaizen_ was coined for this. My point of view of when mass reduction in cost will be when self-driving is cost effect secondary feature on all Toyota vehicles. I see that as the litmus test for knowing that self-driving has reached true utility. Also well designed vehicles would need a multi-sensor system to operate in self-driving mode. A human operating a car is using multi-sensor intake. Lack of multi-sensor in humans prevent them from operating a vehicle. Blind people need a secondary sensory input like walking stick. Vehicles need a multi-sensor system to prevent harming, mutilating, and killing the passengers and pedestrians.
• enslavedrobot 1y ago
  Are you referring to autopilot or FSD? Phantom braking is a solved problem since the release of V12 FSD. As soon as a vision based car is safer than a human, it's flaws don't matter because it will save lives. Supervised FSD is already safer than a human.
  • canadaduane 1y ago
    "Just git pull, and latest fixes it" is not reassuring in this context. Engineers evaluating your claims need real data, not marketing copy.
    • enslavedrobot 1y ago
      FSD is rigorously tested before release. The revisions and updates are safety tested on roads for months before they are released. Tesla also has models that are too big to run on existing production hardware that perform better than the release versions in test cars. Updates are not git pulls and no engineer would ever think that they were.
• danans 1y ago
  > And why not just use LIDAR that can literally see around corners in 3D? Based on what I've read over the years: it costs too much for a consumer vehicle, it creates unwanted "bumps" in the vehicle visual design, and the great man said it wasn't needed. Yes, those reasons are not for technology or safety. They are based on cost, marketing, and personality (of the CEO and fans of the brand).
  • fooblaster 1y ago
    Lidar is being manufactured in china in the volume of millions a year by robosense, Huawei, and hesai. Bom cost is on the order of a few hundred dollars - slightly more than automotive radar. The situation is a lot different in 2025 than in 2017.
• alex1138 1y ago
  [flagged]
  • oblio 1y ago
    > showing Jay Bhattacharya that the old regime had put him on a trends blacklist, and all the other people who got banned for no reason He's doing the exact same thing and worse to people he doesn't like.
    • alex1138 1y ago
      I think it's amazing how I can get downvoted for the smallest of things What you say is plausible, I haven't directly seen the evidence for it but I'm not inclined to completely doubt you But I think back to the time where everything surrounding covid was 'misinformation' and Musk (even if the broken clock is right twice a day) genuinely gave people a place to speak. Old Twitter would shut down people, so fast (even experts)
      • oblio 1y ago
        https://en.m.wikipedia.org/wiki/December_2022_Twitter_suspensions https://en.m.wikipedia.org/wiki/December_2022_Twitter_suspen... https://www.aljazeera.com/economy/2024/8/13/the-right-wing-lurch-of-x-under-elon-musk https://www.aljazeera.com/economy/2024/8/13/the-right-wing-l... You can find this stuff searching 2 minutes on Google. He's just a power hungry oligarch.
• beng-nl 1y ago
  I’ve always wondered about LiDAR - how can multiple units sweep a scene at the same time (as would be the case for multiple cars driving close together, all using lidar)? One unit can’t distinguish return signals between itself and other units, can it?
  • m4rtink 1y ago
    I think it can - I think it might encode something in the beam, use a slightly different wavelength or even just pulse the laser so that the returns don't overlap if timed right.
  • Tadpole9181 1y ago
    Pulse modulation. https://opg.optica.org/oe/fulltext.cfm?uri=oe-31-2-2013&id=524833 https://opg.optica.org/oe/fulltext.cfm?uri=oe-31-2-2013&id=5...
• homefree 1y ago
  I use FSD in my Model S daily to commute from SF to Palo Alto along with most of my other Bay Area driving. It does a better job currently than most people and it drives me 95% of the time now I haven't had the phantom braking. I'm in a 2025 with HW4, but it's dramatic improvement over the last couple of years (previously had a 2018 Model 3) increased my confidence that Elon was right to focus on vision. It wasn't until late last year where I found myself using it more than not, now I use it almost every drive point to point (Cupertino to SF) and it does it. I think people are generally sleeping on how good it is and the politicization means people are under valuing it for stupid reasons. I wouldn't consider a non Tesla because of this (unless it was a stick shift sports car, but that's for different reasons). Their lead is so crazy far ahead it's weird to see this reality and then see the comments on hn that are so wrong. Though I guess it's been that way for years. The position against lidar was that it traps you in a local max, that humans use vision, that roads and signs are designed for vision so you're going to have to solve that problem and when you do lidar becomes a redundant waste. The investment in lidar wastes time from training vision and may make it harder to do so. That's still the case. I love Waymo, but it's doomed to be localized to populated areas with high-res mapping - that's a great business, but it doesn't solve the general problem. If Tesla keeps jumping on the vision lever and solves it they'll win it all. There's nothing in physics that makes that impossible so I think they'll pull it off. I'd really encourage people to here with a bias to dismiss to ignore the comments and just go in real life to try it out for yourself.
  • pbhjpbhj 1y ago
    [flagged]
    • sixQuarks 1y ago
      So he does nazi salutes and is totally buddy buddy with Netanyahu. Ok
      • ksenzee 1y ago
        Those two things are now compatible. Unthinkable for those of us who were around in the 20th century, but now true.
• maxlin 1y ago
  This and that. FUD this FUD that. Tesla have communicated clearly why "adding" LiDAR isn't an improvement for a system with goals as high as their are. Remember, no vision system yet is as good as humans are with vision, so obviously there's a lot to do with vision still. Check this for a reference of how well Tesla's vision-only fares against the competition, where many have LiDAR. Keep it simple wins the game. https://www.youtube.com/watch?v=0xumyEf-WRI https://www.youtube.com/watch?v=0xumyEf-WRI
  • FireBeyond 1y ago
    Is this like the same BS as Elon on an investor call recently? One analyst asked about the reliability of Tesla’s cameras when confronting sun glare, fog, or dust. Musk claimed that the company’s vision system bypasses image processing and instead uses direct photon counting to account for “noise” like glare or dust. This... is horseshit. Photon counting is not something you can do with a regular camera or any camera installed on a Tesla. A photon counting camera doesn't produce imagery that is useful for vision. Even beyond that, it requires a closed environment so that you can you know, count them in a controlled manner, not an open outside atmosphere. It's bullshit. And Elon knows it. He just thinks that you are too stupid to know it and instead think "Oh, yeah, that makes sense, what an awesome idea, why is only Tesla doing this?" and are wowed by Elon's brilliance.
    • maxlin 1y ago
      They referred to using 10 bit / unprocessed sensor data bypassing the normal processing with that terminology. But go ahead fight some weird strawman you built. Did you even look at the video? Don't think you did.
• paradox460 1y ago
  Whats the oddest thing about the wiper tech is that we've had the tech for automated wipers since at least the 70s. As a kid my neighbor's Cadillac had it. tl;dr: you can use optics to determine if there's rain on a surface, from below, without having to use any fancy cameras or anything, just a light source and light sensor. If you're into this sort of thing, you can buy these sensors and use them as a rain sensor, either as binary "yes its rained" or as a tipping bucket replacement: https://rainsensors.com https://rainsensors.com
• debo_ 1y ago
  I upvoted this just for "short-sighted."
• cuttothechase 1y ago
  Cannot agree more on this phantom braking. I rented a Tesla a while back and drove from the bay to the death valley. On clear roads with no hazards whatsoever, the car hit the brakes at highway speeds. It scared the bejeesus out of me! Completely off put by the auto drive and derailed plans to buy a Tesla.
• JumpCrisscross 1y ago
  > maybe there are filters to disregard unlikely objects as irrelevant, which act as guardrails against random braking The filters introduce the problem of incorrectly deleting something that really is there.
• mellosouls 1y ago
  Elon's vision-only move was extremely "short-sighted" (heheh) Careful. HN takes a dim view of puns.
• fred_is_fred 1y ago
  "There are many reasons but that drives it home for me multiple times a week is that my Tesla's wipers will randomly sweep the windshield for absolutely no reason." Self-starting wipers uses some kind of current/voltage measure on the windshield right - unrelated to self-driving? It's been around longer than Tesla - or are you just saying it's another random failure?
• duxup 1y ago
  The around corners thing, when I saw demos of it seeing the vehicles the driver can't even see ... I wanted it for my non self driving car ... it's just too big of an advantage to skimp out on.
• diebeforei485 1y ago
  How does lidar see around corners?
  • xnx 1y ago
    Waymo sensor pods are mounted at the corners of the vehicle allowing it to see things that a driver can't. (E.g. when pulling out of an alley)
    • diebeforei485 1y ago
      That's not "seeing around corners", that's just sensor placement and can also be done with cameras. Tesla's side cameras on the front are in a similar location.
• teleforce 1y ago
  >why not just use LIDAR that can literally see around corners in 3D? LIDAR requires line-of-sight (LoS) hence cannot see around conner, but RADAR probably can. It's interesting to note that the all time 2nd most popular post on Tesla is 9 years ago on its full self driving hardware (just 2nd after the controversial Cybertruck) [1]. >Elon's vision-only move was extremely "short-sighted" Elon's vision was misguided because some of the technologists at the time including him seem to really truly believed that AGI is just around the corner (pun attended). Now most of the tech people gave up on AGI claim blaming on the blurry definition of AGI but for me the truly killer AGI application is always full autonomous level 5 driving with only human level sensor perceptions minus the LIDAR and RADAR. But the complexity of the goal is very complicated that I really truly believe it will not be achieved in foreseeable future. [1] All Tesla Cars Being Produced Now Have Full Self-Driving Hardware (2016 - 1090 comments): https://news.ycombinator.com/item?id=12748863 https://news.ycombinator.com/item?id=12748863