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Standardizing Automotive Connectivity

tesla.com

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Re: Standardizing Automotive Connectivity

#121

Post by cyberax »

numpad0 wrote: post #105
cyberax wrote: post #102

Earlier quoted context omitted.

More robust, cheaper (far simpler wiring harness), eventually ability to do zonal assembly.

Are BMW cars less reliable, expensive, not ready for zonal assembly...? Major car components like doors or front axles are assembled in parallel to miscellaneous parts on the main body, and all .join() at the final assembly. This had been the case for past 30-50 years, possibly more, in case this needs to be said.

They can be even more reliable. And they definitely _are_ expensive.

> Major car components like doors or front axles are assembled in parallel

And doors (and tailgates) are the biggest body component that is _sometimes_ assembled independently. Then workers manually route cables through the body.

Pre-routing cables inside panels that can then just be welded together can save a lot of labor.

Re: Standardizing Automotive Connectivity

#122

Post by cyberax »

typewithrhythm wrote: post #104
cyberax wrote: post #101

Earlier quoted context omitted.

They don't need to retool all the factories at once. They could have gradually introduced 48V systems in parallel with 12V, slowly phasing in new components as they replaced the old 12V.

Converting between voltages is not a free action, and running two systems is more complicated than one... You really need some special component that is much better at 48 for it to be worth it, otherwise a delayed platform switch is better; one some competitors have moved and the suppliers exist.

Starter motor, power steering, heated seats, powerful headlights, power-hungry onboard computers.

They _all_ benefit from 48V.

Re: Standardizing Automotive Connectivity

#123

Post by maxerickson »

Animats wrote: post #55

Those look much like AMP automotive connectors. Using one kind of unkeyed connector in a car may be a bad idea. Things can be plugged in wrong during repairs. There's a lot to be said for making connectors not fit where they shouldn't. Especially in automotive, where many connectors are plugged in blind, by feel. This simplifies manufacturing at the cost of repair. If it can be plugged in wrong, it will be plugged in…

At least reverse battery protection is pretty standard these days.

Doesn't make things work when they are plugged into the wrong connector, but they should still work once the connections are straightened out.

Re: Standardizing Automotive Connectivity

#124

Post by maxerickson »

numpad0 wrote: post #112
m463 wrote: post #97

Earlier quoted context omitted.

I'll bet a hidden factor here is development and testing. They can probably develop for a car ethernet lan with a desktop pc and car "peripherals". Not that there aren't canbus cards for pcs, but still.

This sounds like the real answer. Replacing an automotive standard with Ethernet is going to reduce friction onboarding junior webdevs with MacBooks, and enable a more stable higher turnover labor intensive organization.

CAN to PC adapters are a few hundred dollars, it isn't causing much friction.

Re: Standardizing Automotive Connectivity

#125

Post by shiroiushi »

cyberax wrote: post #122
typewithrhythm wrote: post #104

Earlier quoted context omitted.

Converting between voltages is not a free action, and running two systems is more complicated than one... You really need some special component that is much better at 48 for it to be worth it, otherwise a delayed platform switch is better; one some competitors have moved and the suppliers exist.

Starter motor, power steering, heated seats, powerful headlights, power-hungry onboard computers. They _all_ benefit from 48V.

On top of all that, almost all the wiring in the car can be made thinner, because of the greatly reduced losses. This saves a bit of weight, but also a lot of cost because copper is expensive.

Re: Standardizing Automotive Connectivity

#126

Post by phlipski »

cyberax wrote: post #90
throw0101d wrote: post #71

Earlier quoted context omitted.

> Tesla really deserves some kudos for pushing the 48V architecture and the Ethernet-based communication. For the record, 42V systems were experimented with in the 1990s: * https://en.wikipedia.org/wiki/42-volt_electrical_system In the 2011 German automakers agreed to 48V as the next step after 12V: * https://en.wikipedia.org/wiki/48-volt_electrical_system BMW was the first the first with Ethernet: * https://www.marv…

This has been a real head-scratcher for me. BMW and other automakers could have vastly improved their cars by switching to 48V a decade ago, but they still keep just plodding along with 12V. I have no explanation for this.

It's a classic chicken and egg economic problem. BMW doesn't make the chips/electronics that support the 48V architecture - Bosch & Continental (with NXP/TI/Infineon/Renesas as their silicon suppliers) do and they're not going to support 48V unless ALL (or a significant majority) of the automakers will. So it's a game of chicken.

Re: Standardizing Automotive Connectivity

#127

Post by cyberax »

JoshTriplett wrote: post #106
outworlder wrote: post #22

Earlier quoted context omitted.

We can simplify the wire mess today by using more CAN bus devices. What is ethernet bringing to the picture?

CAN has desirable electrical properties (e.g. hardware-level prioritization) if you have life-critical devices and non-life-critical devices on the same network. But it's painful to deal with from a software point of view, compared to IP-based protocols, for anything that doesn't require the properties of CAN.

Industrial Ethernet (PROFINET) also has priorities and bandwidth reservation: https://en.wikipedia.org/wiki/Profinet#Technology_of_Class_C...

Re: Standardizing Automotive Connectivity

#128

Post by numpad0 »

cyberax wrote: post #122
typewithrhythm wrote: post #104

Earlier quoted context omitted.

Converting between voltages is not a free action, and running two systems is more complicated than one... You really need some special component that is much better at 48 for it to be worth it, otherwise a delayed platform switch is better; one some competitors have moved and the suppliers exist.

Starter motor, power steering, heated seats, powerful headlights, power-hungry onboard computers. They _all_ benefit from 48V.

I'm sorry but the other comment is more correct. 48V standard was originally created for mild hybrid systems for ICEs during mid-2000s as a stopgap solution to full hybrid transition. Looks like the earliest mass-production 48V-class system was a 2001 Toyota that ran at 36V.

The integrated starter generator(ISG) is usually a pancake shaped motor that replaces clutch/torque converter in ICE car, nothing like the regular starter motor.

MHV was not even real hybrid, and is no longer relevant, so was 48V, at least for a while.

Re: Standardizing Automotive Connectivity

#129

Post by maxerickson »

phlipski wrote: post #126
cyberax wrote: post #90

Earlier quoted context omitted.

This has been a real head-scratcher for me. BMW and other automakers could have vastly improved their cars by switching to 48V a decade ago, but they still keep just plodding along with 12V. I have no explanation for this.

It's a classic chicken and egg economic problem. BMW doesn't make the chips/electronics that support the 48V architecture - Bosch & Continental (with NXP/TI/Infineon/Renesas as their silicon suppliers) do and they're not going to support 48V unless ALL (or a significant majority) of the automakers will. So it's a game of chicken.

The semiconductors have been available for 20 years.

Re: Standardizing Automotive Connectivity

#130

Post by numpad0 »

cyberax wrote: post #121
numpad0 wrote: post #105

Earlier quoted context omitted.

Are BMW cars less reliable, expensive, not ready for zonal assembly...? Major car components like doors or front axles are assembled in parallel to miscellaneous parts on the main body, and all .join() at the final assembly. This had been the case for past 30-50 years, possibly more, in case this needs to be said.

They can be even more reliable. And they definitely _are_ expensive. > Major car components like doors or front axles are assembled in parallel And doors (and tailgates) are the biggest body component that is _sometimes_ assembled independently. Then workers manually route cables through the body. Pre-routing cables inside panels that can then just be welded together can save a lot of labor.

> And doors (and tailgates) are the biggest body component that is _sometimes_ assembled independently.

Sometimes? What and when on Earth is this about? Pre-WWII?

They wash and paint and dry the whole body at once _for paint consistency_, then take off doors and trunk lids and bumpers and send them into separate assembly lines. Those major parts flow parallel "threads" in sync and converge near the end, where connectors are plugged in and those major parts are bolted back in and plastic trims are pushed in to tuck everything under. Cars were basically always done that way for a long time everywhere. I think even lots of hand made supercars are like that, only except tact times are magnitudes longer.

> Then workers manually route cables through the body.

> Pre-routing cables inside panels that can then just be welded together can save a lot of labor.

What do these even mean? Are you hallucinating workers crimping cables in-situ? They just clip on harnesses and plug in couplers in "the line". Never seen under a door trim?

It sounds like you're either extremely ill-informed, or worse yet, potentially, intentionally misinformed about car manufacturing that what you see is advanced manufacturing. I think you should... look more closely into what "legacy auto" have been doing forever.

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