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Changes to Models S and X allow them to travel longer without larger batteries

tesla.com

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Re: Changes to Models S and X allow them to travel longer without larger batteries

#321

Earlier quoted context omitted.

They break at much much lower rates, because they have many fewer parts. EVs don't have the pistons, valves, belts, fans, compressors, alternators, spark plugs, etc that gasoline engines have. There's probably order of magnitude fewer parts to break. Having seen the interior of an automatic gearbox, the surprising thing to me is that conventional automobiles are as reliable as they are.

I have had just as many issues with things braking unrelated to the engine. Eg washer fluid bottle leaking, air conditioning, disk breaks needing replacing, tire sensors breaking, tires going bald, etc. Out of the engine related problems, the cam belt and clutch are the things that's caused issues in the last 5 years across my various cars.

Those are far easier to handle than, for example, changing a timing belt on a gasoline engine. Faster too...

You need less qualified people, less time, less parts, less often for repairs that a handy person can often do themselves and save on labor and parts. Significant sources of income are therefore shrunk for dealerships.

Re: Changes to Models S and X allow them to travel longer without larger batteries

#322

Earlier quoted context omitted.

Is it any worse than what other manufacturers deal with? The 2019 Honda Accord shares some parts with the 2018 Honda Accord which shares some parts with the 2017 model... when something breaks in my Honda the first question is "do they still make/use this part or did they change it in newer models?"

A former Tesla employee, who worked on their IT infrastructure and whose NDA has expired, has revealed the technical shit show going on behind the scenes at Tesla. (I'm a Tesla fanboy as well, but this is scary). https://twitter.com/atomicthumbs/status/1032939617404645376

If someone wants to copy-paste some parts instead of pictures, here's the link to all his posts in that thread.

https://forums.somethingawful.com/showthread.php?threadid=38...

Re: Changes to Models S and X allow them to travel longer without larger batteries

#323
I'm wondering what types of range extension methods could be easily added to an EV. Scenario: I'm going to drive 900km/560mi and it's -10 outside (I do this multiple times per year). I want a cosy room temperature inside the cabin.

- How can I ensure I waste as little range as possible on heating, so that I don't risk having to make e.g. 2 stops instead of one?

- More critically, if I get stuck in traffic for several hours because of an accident, I need some way to ensure I don't freeze to death in my EV as I'm standing still and the battery runs out.

It seems these two things should be solvable with a single solution: a plug-in space heater to be used in emergencies and for maximizing cold weather range. The space heater could be e.g. a kerosene burner or similar. But for best effect it should of course "plug in" to the car vents.

Is this a thing? Or is heating the passenger compartment such a trivial use of energy anyway if the car is insulated, that it doesn't make a difference? In a concrete scenario: If I drive a model 3 and have 100km battery left, and I have 20km to my planned charging stop half way through my journey. Suddenly traffic stands still because of an accident and it's freezing outside. How long will the "100km" charge maintain the 30K temperature difference while still having 20km left?

Re: Changes to Models S and X allow them to travel longer without larger batteries

#324

Earlier quoted context omitted.

Not to me. I judge Tesla on the same metrics as any other car company. The Model S is getting long in the tooth.

Really? So many models live forever. Do you think the "Mustang" is long in the tooth?

For what it’s worth, the Mustang had a somewhat significant refresh in 2011 (totally new engine design, but not considered a new generation), then another refresh around 2014 (mostly exterior body changes IIRC).

Re: Changes to Models S and X allow them to travel longer without larger batteries

#325
post #260

Earlier quoted context omitted.

> EVs don't need the large established dealership base and their included maintenance facilities I never understood that. Why does power source matter in the context of dealership base and maintenance? EVs still break.

They break at much much lower rates, because they have many fewer parts. EVs don't have the pistons, valves, belts, fans, compressors, alternators, spark plugs, etc that gasoline engines have. There's probably order of magnitude fewer parts to break. Having seen the interior of an automatic gearbox, the surprising thing to me is that conventional automobiles are as reliable as they are.

But the number of required service stations is also a function of how many customers you have and how they are distributed gographically, not only of how often they visit a station?

Surely you don't want people to drive 200km to the nearest service station, no matter if that's once a year or once every 3 years? Maybe that's the difference - customers expect EVs to be bleeding edge, so the service can be a hassle, and you can still get away with it?

Re: Changes to Models S and X allow them to travel longer without larger batteries

#326
post #128
post #82

Earlier quoted context omitted.

Range and acceleration mostly go hand in hand. Much of the constraint on acceleration is how much power you can pull from the battery pack, and that gets better with larger batteries. It’s not like a normal car where high acceleration means a big, inefficient engine.

Agreed, that was why I noted the efficiency model for an electric engine is superior to ICE. I'd just rather "normal"-ish acceleration in traffic with range improvements over high max acceleration. I'm sure you could also reduce engine weight if you don't have to rely on extreme acceleration.

The motor is pretty small. The benefit from making it weaker would be tiny, if any.

Re: Changes to Models S and X allow them to travel longer without larger batteries

#327
post #269

Earlier quoted context omitted.

If you believe that they are doing false advertising around FSD, could they also be doing false advertising about this?

Unlikely about battery capacity and range. Tesla have consistently delivered in that side of things. The core of their car business is solid. Their problem on the production side is not surprising. Missing deadlines and production targets is business as usual for "startups" (between quotes because they are massive, however still very much a new and small player in that field) "We will deliver million of widget in 2 y…

Independent researchers have already proven Musk to be 100% right about LIDAR.

Pseudo-LiDAR from Visual Depth Estimation: Bridging the Gap in 3D Object Detection for Autonomous Driving https://arxiv.org/abs/1812.07179

3D object detection is an essential task in autonomous driving. Recent techniques excel with highly accurate detection rates, provided the 3D input data is obtained from precise but expensive LiDAR technology. Approaches based on cheaper monocular or stereo imagery data have, until now, resulted in drastically lower accuracies --- a gap that is commonly attributed to poor image-based depth estimation. However, in this paper we argue that data representation (rather than its quality) accounts for the majority of the difference. Taking the inner workings of convolutional neural networks into consideration, we propose to convert image-based depth maps to pseudo-LiDAR representations --- essentially mimicking LiDAR signal. With this representation we can apply different existing LiDAR-based detection algorithms. On the popular KITTI benchmark, our approach achieves impressive improvements over the existing state-of-the-art in image-based performance --- raising the detection accuracy of objects within 30m range from the previous state-of-the-art of 22% to an unprecedented 74%. At the time of submission our algorithm holds the highest entry on the KITTI 3D object detection leaderboard for stereo image based approaches.

Karpathy was also pointing to:

Depth from Videos in the Wild: Unsupervised Monocular Depth Learning from Unknown Cameras https://arxiv.org/abs/1904.04998

We present a novel method for simultaneous learning of depth, egomotion, object motion, and camera intrinsics from monocular videos, using only consistency across neighboring video frames as supervision signal. Similarly to prior work, our method learns by applying differentiable warping to frames and comparing the result to adjacent ones, but it provides several improvements: We address occlusions geometrically and differentiably, directly using the depth maps as predicted during training. We introduce randomized layer normalization, a novel powerful regularizer, and we account for object motion relative to the scene. To the best of our knowledge, our work is the first to learn the camera intrinsic parameters, including lens distortion, from video in an unsupervised manner, thereby allowing us to extract accurate depth and motion from arbitrary videos of unknown origin at scale. We evaluate our results on the Cityscapes, KITTI and EuRoC datasets, establishing new state of the art on depth prediction and odometry, and demonstrate qualitatively that depth prediction can be learned from a collection of YouTube videos.

Tesla has also advantage of having radars and is able to do supervised learning of depth estimates for moving objects from video.

I was also skeptical of Tesla self-driving capability, because they had some stupid ideas, like ignoring radar data based on GPS tagging from fleet behavior. But lack of LIDAR will not be the issue. Not even close.

It seems like they are focusing on building proper pipeline for training neural networks. The question is whether neural networks as a technology can handle self driving. Reasoning based on "human brain can do it, so artificial neural networks can do it" is wrong. Natural neural networks and artificial neural networks, besides name share only very, very rough low level conceptual ideas. Moreover, our ANN architectures are probably missing most of what brains do on high level. So, I think this is still an open question - can ANN do it? If not, then nobody will have full self driving capability widely deployed any time soon. Because, even tough neural networks are not perfect, everything else is super brittle in comparison.

LIDAR and hires maps are technologies that give working short-term solution, are sort of local minimum. LIDAR is super expensive and already proven to be not necessary. While, hires maps are super brittle and too capital intensive to be widely deployed.

But if neural networks are sufficient Tesla will leave everyone in dust. There will be literally no competition. They do not need to learn electric cars manufacturing in order to deploy their technology widely, they are doing that already. They will not need to backtrack on LIDAR and hires maps solutions. Also, their decision to deploy self driving hardware to every car means that they have access to stupidly big amount of real world data from all varieties of environments all around the world.

BTW - Extrapolating based what Tesla was doing before Karpathy joined is probably misguided. I was afraid that he will get lost in a big corporation, but he seems to be doing great job there. In my opinion technology that build with his supervision will be significantly better than what Tesla was doing before. But Karpathy is not a magician.

So, Tesla has the biggest potential and the big question is: Are neural networks sufficient for self driving?

Re: Changes to Models S and X allow them to travel longer without larger batteries

#328
post #308

Compare to the Audi e-Tron, which has a fairly massive 95kWH battery but only scores 204 miles of EPA range. They claim they're only using 88% of the battery capacity so that charging is faster and battery longevity is preserved, but thats a really weird engineering decision that belies the fact they have made a terribly inefficient (and perhaps rapidly degrading?) battery pack/drivetrain. Meanwhile the base Model S,…

A rising tide lifts all boats. I'm just happy there are an increasing number of EVs coming on the market. And people will have their reasons for choosing one or another, so it doesn't have to be that one car is objectively best across the board and therefore gets 100% of the sales. I'm very happy with my Model 3 but what I really want to see is acceptance of electric cars as a viable and sensible option for a lot of…

Of course. I'm not trying to play a game of 'my EV is better than that EV' (nb I drive a Leaf). I'm pointing out that many people underestimated the lead Tesla has in EV technology. This year we've seen major, and esteemed, automakers put things into production that are clearly years behind what Tesla can do. I'm glad they are joining in, but I'm just trying to set the record straight.

FWIW the Kia Niro EV (and the Hyundai Kona Electric which is based on the same platform) are very serious competitors for the Model 3. Kia and Hyundai seem to have got the EV tech figured out. But alas they can't hardly manufacture any of them. So thats Tesla's other advantage - a whopping huge battery factory.

Re: Changes to Models S and X allow them to travel longer without larger batteries

#329

Earlier quoted context omitted.

Service intervals are very limited. Let me use my Model 3 as an example, I only need tire rotations until 25,000 miles. At that point I need the cabin and HVAC air filters replaced, then 25k later I do it again. Not only will dealership service centers be impacted, oil change shops will have little work if any as the number of petrol cars wind down, general service shops face the same issue as the numbers decline. No…

That's not super different from long lasting oil? Some Petrol cars do 30'000km without and service?

They can and will with the correct supplies and parts (and handling).

There is a reason that some oils are far more expensive than others. Oil change shops have an incentive to make you come back soon, so you will be told there is no need for the more expensive oil. The composition of the oil and the quality of the engine and its parts will of course influence the build up of slug.

Re: Changes to Models S and X allow them to travel longer without larger batteries

#330
post #260

Earlier quoted context omitted.

> EVs don't need the large established dealership base and their included maintenance facilities I never understood that. Why does power source matter in the context of dealership base and maintenance? EVs still break.

They break at much much lower rates, because they have many fewer parts. EVs don't have the pistons, valves, belts, fans, compressors, alternators, spark plugs, etc that gasoline engines have. There's probably order of magnitude fewer parts to break. Having seen the interior of an automatic gearbox, the surprising thing to me is that conventional automobiles are as reliable as they are.

I hate to break it to you but very few vehicles are going to the dealer for engine/trans related work. Dealerships mostly only see vehicles that are new enough to be under warranty or recently out of it and major power-train stuff doesn't often break in that time period. It's stuff like steering and suspension wear items, the occasional window motor, trunk latches that won't pop, HVAC and stuff like that they make most of their money doing. EVs would probably actually net more money for dealers more money because they wouldn't take a loss on fixing random leaks under warranty (they get paid but book times are often unrealistic).
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