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Comment by bayindirh | Hacker News Reader

From the article:

> Mobile phone SOCs integrate a substantial amount of function right onto the chip. Why hasn’t that been the case for the car?

Because your mobile phone SoC is not certified for -20/+80 degrees Celsius, copious amount of vibration, error-free operation on many environments (incl. inputs with wrong voltages, shorts, etc.), and have a lifetime of 10+ years with the same performance characteristics.

Your car is running a real-time simulation of your engine to keep itself operational, and it's a much serious business than running Android or iOS.

More information: https://media.ccc.de/v/32c3-7331-the_exhaust_emissions_scand...

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They do however use SoCs for HMI/head-units/carputers now however.

The bigger reason is just the nature of automotive development. Every part is developed by a specced or sourced by different teams and outsourced to a different Tier 1/2/3. Things are designed to be modular, so if you pick Option A for something, it might use ECU A, and if you pick Option B, they might pack a whole different ECU B. Also, every ECU is costed down to only support the intended application, so ECU A likely doesn't have the extra bandwidth to add on extra features for Option B.

Also, none of this is decided or developed at the same time, so you have all the different features and ECUs developed throughout. Some things are changed mid program. Some things carry over from previous programs, so it's usually just easier to go your own way and not work with other teams on combining features.

Every automotive OEM has a person who comes up with the brilliant and cost saving idea of combining ECUs. I know 4 such people from different OEMs but they have all failed for some of the reasons mentioned above.

SoCs in head-units would still be automotive qualified variants (temperature grade, etc).

-20 ° C - + 80 °C is for keyfobs. For ECUs in the passenger compartment is -40°C - 85 °C and for ECUs in the engine compartment is -40 °C - 105 °C.

When you buy semiconductors on digikey or whatever, there are several different 'classes' of performance. Everyone imagines milspec being the top one, and it's true, but for most people the ideal class is 'automotive'... Because precisely of what the parent said: tolerances of temperatures to 140F or more. Think of a car sitting in a baking parking lot in Phoenix, no shade.

You don't build semiconductors for that purpose by using 10nm process then adding a lot more redundancies when all you need is a simple opamp. You instead build the thing beefy and resistant to the environment.

And all the excitement over new chip plants by TSMC etc, won't do a thing for these automotive applications.

There are classes ABOVE mil-spec. These are several "Space grade" classes above mil-spec which have far wider temperature and radiation ranges.

Also... mobile phone SoC are made in much higher quantities then car chips: there are much more phones shipped then cars. Therefore R&D costs per unit are significantly lower with phone chips and you can spend more.

>> SoC is not certified for -20/+80 degrees Celsius

That is basically the operating range of the average graphics card these days. Not many people go sub-ambient with their cooling but no graphics card would complain if they did. The actual silicon is perfectly fine with such temperatures. The only real issue is the external cooling rig, a classic engineering problem that any car company shouldn't have a problem solving. A water cooler tied to the vehicle's coolant loop would easily cap the upper temperature range at water boiling points. A car engine has plenty of power available for fans or even air conditioning if necessary. Hide the controller chips somewhere in the passenger compartment and the humans will die of heat before the silicon.

I’m not talking about processor temperatures. The temperatures I’m talking about are ambient/enclosure temperatures. So, the board, and all integrated components will be at least that ambient temperature, and they’ll work without any transient errors.

Also this means, no solder joints or any other component won’t act funky.

A transient error in your GPU is a one pixel blip. In an ECU, that’s a power loss event in best case.

In low temperatures you start having issues with moisture saturating the air. Things get wet out of nowhere. There are also electrolytic capacitors which are water based so these need to be ruled out as well. Given air has at any given time a lot of water and water goes through a phase change at sub zero i find the comparison quite invalid.

That's a difference with automotive/aviation products. They will all be in sealed containers and then the actual circuitry will all be covered in plastic. There shouldn't be any exposed metal that could possibly short, even if immersed in water. Pouring buckets of water on a running engine (ie a gap in the hood closure on a rainy day) or even into the passenger compartment (ie sunroof left open) shouldn't do much of anything to a car's electrical systems.

(This is also done for fire safety reasons. Any metal that could possibly short if wet could also ignite a fire during/after a crash.)

Just as an example, a BY Audi has it's TCM (transmission) module under the us passengers side floor carpeting. It is in 'a box", but the box is in no way sealed. The metal box that is the TCM as a whole is made of metal, and maybe attempted to be sealed a bite but isn't sealed.

B6 Audis have a design problem with their sunroof drains. When they clog up, unknown to you, the water will pool in passengers footwell area. It takes a while to notice this as a person, as there is 4-6" of foam padding between the metal floor of the car, and where you rest your feet . The TCM lives between these layers, and eventually, in the lake that will form, submerging your TCM -- leaving you with yet another reason to hate your Audi.

This is early 2000's. Late 200* a8 models had I believe 30+ different "computers" living in the same over metal under foam situation.

An aside, if you ever wash the engine bay of a car with low pressure water, I'd suggest covering the blatant electronic bits with some plastic bags, and leave the car idling when you do so -- that way if/when it starts to sputter or just dies, you have a general idea of where it all went wrong.

They really are not as water tight as we all assume.

This is early 2000's. Late 200 a8 models had I believe 30+ different "computers" living in the same over metal under foam situation.*

I now have secondhand PTSD from reading this, and thinking about the Audi owners who have found out the hard way.

Dead leaves caught in your sunroof can make your transmission flake out. I'm sure the owner's manual, on page 935, instructs you to ream out the drains with a pipe-cleaner every 5,000km so that your car can shift properly. The only word I can think of for this is..."perverted".

It only took one early 2000s Audi for me to swear off German cars for the foreseeable future. I don't know that their questionable design choices are applicable to the rest of the industry's chip practices.

Story time:

Around that time they saved a few bucks by switching the thermostat housing from metal to plastic and not changing the design at all so that it could be a drop-in replacement. With that distinct lack of engineering effort, they were prone to splitting at corner-induced stress lines in the plastic.

In an ordinary car this wouldn't be an issue; thermostats fail regularly, so their housings are readily accessible -- kind of like how most cars make changing the oil filter a manageable task. In an Audi however, the process is to take the front half of the car off to expose the engine, take the front half of the engine off, and then replace the now easily spotted housing.

So anyway, I don't know of a better place for the thermostat housing to split in half (leaking coolant out faster than you can pour it in) than the middle of fucking nowhere WY. By this time mobile phones were pretty common, but I swear to God they were sharing a single 1Mbps connection across ten counties; only about every third Google search would succeed without timing out, and as a precursor to learning how to take apart my car it was quite literally faster to code up a crude strip-the-garbage proxy (paginating compressed text and nothing else to send back) and deploy that to a home server than it was to try to surf the modern web over at best a 1k connection.

In retrospect the coding wasn't necessary since speeds increased to something manageable in the wee hours of the morning when everyone else was asleep and since it was absolutely not a 1-day job, but it was a bit of a fun experience anyway.

By sealed you mean enclosed but not air tight right? Air tight sealing would require a pressure vessel for electronics which i never saw both on airplanes nor on cars.

The plastic coating though, I have seen. Such coating completely changes the thermals of the electronics making the OPs claims that a home GPU could just be strapped into a car very unlikely.

> Your car is running a real-time simulation of your engine to keep itself operational, and it's a much serious business than running Android or iOS.

Well, it takes some parameters, goes into a lookup table and decides how much timing to retard, or fuel to give, and probably has a o2 sensor, checks knocking, etc. All done on pretty barebones 80's tech.

You're right on the tables part, but these are the words of the guy who worked on BMW for 14 years, who's on the video.

And, as a person who's doing simulation coding, I tend to behave to him about that.

The relevant part starts here: https://media.ccc.de/v/32c3-7331-the_exhaust_emissions_scand...

>Your car is running a real-time simulation of your engine to keep itself operational, and it's a much serious business than running Android or iOS.

Lets not exaggerate :) ECU reads a bunch of sensors, does some mild compute, uses that to do a table lookup, interpolates and slaps the result into actuators. 8bit 10MHz is enough to accomplish this task.

These are not my words. See https://news.ycombinator.com/item?id=30875680

How does functional integration interfere with robustness?

One method of making a chip 'tougher' is to physically increase the size of the semiconductor elements (e.g. transistors, FETs). This would seem incompatible with highly-integrated ICs.

This is true. For radiation hardening for space, this is exactly what is required for anything more harsh than LEO. And as a consequence, the generation of processors and memory typically used are 10-20 years behind the current state of the art. That's simply the price of reliability in harsh environments!

The discrete components are designed, tested and verified after a long stint and their specs are frozen. It's a bit like space hardware. You verify an older CPU design can work reliably in space, and certify that processor. Then, you use the same foundation for a decade or so.

It's same with automotive industry. You have a well defined and certified stack from Delco, Bosch, Delphi, etc. and you can trust that hardware. Integration makes you return back to square one.

I remember Toyota tried unifying some control units into a single box, and 5-6 years considered realistic if not a little optimistic.

To add to that, some of these features are extremely specialized, and for each feature, 1-2 of the big players might have a huge technical advantage and economies of scale in production and in supplying. This leads to higher barrier to entry and not enough margin for other players to replicate the feature.

Funny, this sounds exactly like why microservices have an advantage over monoliths in big organizations.

SpaceX works around that by using consumer grade stuff and just replicating it 3 times. Tesla also managed to handle issues with supply shortages very well.

The old practices are just not good enough.

> SpaceX works around that by using consumer grade stuff and just replicating it 3 times

Falcons get refurbished after short flights. That reduces the emphasis on durability. Redundancy defends against random errors, reducing the need for radiation hardening. It does less against wear and tear.

> The old practices are just not good enough.

True, but also think about the path dependence of the old companies. They have withered a lot of ups and downs, they are not the innovators, they are the very slow incrementalists that despite this release a new boring model every few years dressed up as the new best thing ever. (If you have seen a car from one manufacturer you have seen them all from them for the past decades too.)

The whole car industry is a relatively high volume & low margin & medium risk business. (The unit economics is great, but any risk kills profitability, so there was a lot of consolidation and convergence.)

Basically the car industry is like the "iphone industry" except there's some actual price competition and worse fundamentals, plus Apple is relatively young (and Steve set up a pretty high pace, and expectations, plus the fundamentals of the components - eg. semi industry, radios, displays - are really moving forward, whereas internal combustion engines, and the material science of other car components are not).

it's really fantastic though, for parts availability and reliability. People don't remember how absolute shit any pre-80's vehicle is. Like, shit tier reliability from carbs, tune ups, constant work. 100k? that car is dead and done! Now the average vehicle age has been climbing and climbing. The best part is that 2005 brake caliper is probably just a slightly more refined version from the 90's

Yes, exactly, no questions there :) I remember here in the 90s (barely post-USSR Hungary) going anywhere with a typical car was almost like a choose your own adventure, where adventure meant something will randomly go wrong, and if you are lucky you have spare parts with you, or maybe you can simply find a workaround (for example when the cooling system loses all the water because the radiator suddenly bursts means you could still make progress, of course slow and stopping if the engine gets too hot). And in the early 90s nobody had mobile phones, so it involved a bit of hitchhiking to the nearest phone too!

Cars tend to fail more disastrously now, but less often. If my coil back goes I am SOL. There's a reason they tell you to keep one in the trunk. The difference to that and a cap+rotor is, a cap and rotor is about 12 bucks and can be done on the side of the road without tools, and that cap and rotor fits about 50 million 4 cylinders manufactured in the last 50 years, and tends to degrade more gracefully.

On the flip side, cars now tend to run more efficiently till they break fully and go into limp mode or won't run - a lot less tuneups and tweaking, no adjusting the valves and carb as the car ages

I've lost coil twice. Once was during driving. I lost a single cylinder, check engine light turned on. I was able to drive up to 70Km/h without my check engine light start blinking (means "you can melt your catalytic convertor, exhaust is too fuel rich, reduce throttle!").

Went to my service guy, he put down his tea on my engine, replaced it and his tea was half (~10 minutes). Also put in a new set of plug wires since my set was ~18 years old and gone hard at that point.

I went to office, lost 30-40 minutes at most.

The second one happened when the car was at park, at night. Started it in the morning, it was running off, so went to service. Same story. 70Km/h speed, 10 minute change, sans the cables this time.

Newer cars tend to use one per plug. It's just a disconnect, pop-off, push in, plug, go. 2-3 minutes at most.

yeah, this is actually something we are looking at for the Saab T5 engine series. It uses an integrated coil pack for all the cylinders, which in turn means, a failure of one is a failure of all. I know some of the tuners have switched to using more normal coil pack setups, but unfortunately the T5 system is pretty unique so its not a thing that can be easily hot swapped.

One interesting tidbit is the coil packs run a bit of current over the plug when it's not sparking to measure ionization to determine engine conditions (i think mostly knock)

> It uses an integrated coil pack for all the cylinders, which in turn means, a failure of one is a failure of all.

That’s interesting. My coil pack is also integrated, but it’s designed to fail independently. Maybe it’s the design of the coil, but not an inherent shortcoming of the system itself.

> One interesting tidbit is the coil packs run a bit of current over the plug when it's not sparking to measure ionization to determine engine conditions (i think mostly knock)

Didn’t know that. I knew that engine knock was measured with vibration sensors, crank position relative to other things and engine output measurements via load sensors (irregularity), but ionization measurement is new to me. Have any sources, so I can read more?

I think it was basically since Saab was fairly early to the coil pack game, these "Direct Ignition Cassettes" was in production in 88...

Yeah... no standard knock sensor, which is the normal way to do things, but it's much improved because a regular knock sensor on a 900 can't really tell, what cylinder is knocking (and no cylinder behaves the same, regardless of what you do), so on a distributed 900 with the Bosch systems, it'll hold boost back or (with ezk) retard knocking for a few full cycles.

With ionization it can determine -which- cylinder is knocking and adjust timing and fuel on that one specifically

Here's a good article

https://eeuroparts.com/blog/tech-corner-saab-trionic-and-ion...

That was an awesome read, thank you!

Tesla is not a car. It looks like one, it might behave a bit like one but i would not touch such a thing even with a 9 m pole. I heard too many horror stories about Tesla requirements.

If it looks like a duck (car), and moves like a duck (car), and quacks like a duck (car), then it's a duck (car) in my book.

What other thing should it have? An ICE? Then Nissan Leaf, Ford F150 electric, and BMW i series are not cars either.

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