
Tesla reveals revolutionary new wiring architecture to help robots build cars - evo_9
https://electrek.co/2019/07/22/tesla-revolutionary-wiring-architecture-robots-model-y/
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Glawen
So the idea is to make ecu in the vicinity to be responsible of the
components, and drive them through communications.

Nothing new, trucks are applying this technique already.

The big drawback is that it increases SW and systems complexity. You cannot
believe how few of the SW guys in the automotive industry have a clue about
CAN (or flexray) communications and its failures mode. Its unbelievable how
much code does not react properly on Communications failures / init / lag.

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m463
I know someone who used to work on BMWs and he said when they first came out
with the lan-based car wiring problems were almost impossible to diagnose.
Basically the shops would just swap parts until something worked. I think it's
gotten better now as things have matured.

I expect because tesla is doing it in SV, they have enough software guys
available to figure things out (and maybe frontload the diagnostics to make
servicing things easier).

That's how technology works - make cheaper and less sophisticated hardware do
more and better.

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Glawen
I don't see how this would help, because the default behaviour in a computer
software is to inform the user that an error occured, please press enter to
continue.

When you write software for a car, you always have to think about the impact
of your code in the car, and pressing enter or crashing the sw is not the safe
way to respond. So if the comms fails, you have to ask yourself what should
the thing you're writing do and what the driver would see or think.

The problem with this architecture is that when you have a physical sensor, it
is obvious when it fails and you can easily add contingencies. When you have a
sensor other CAN or whatever, you are adding new failure modes: sensor OK but
communication not reliable, or sensor info not yet received. You thus need
more code to handle those new failure modes which are tricky for the average
sw guy.

~~~
m463
This is generally how everything computerized is developed.

The hardware is simplified and the software becomes more sophisticated. In
this case, the recurring costs are minimized (simplified wiring harnesses that
are installed via automation) in favor of an increase in non-recurring costs
(more up-front engineering time).

The failure modes of these kinds of designs are by now a solved problem. The
fact that automated assembly of simpler wiring harnesses occurs might mean the
hardware reliability goes up.

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gamblor956
Tesla has finally discovered subassemblies and the concept of minimizing
wiring.

Other car companies have been using both for years...even decades, in Toyota's
case (the original pioneer behind using subassemblies in automotive design).

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lsllc
How is this different architecturally from typical structured wiring in
networking, or say the arrangement of USB controllers within a typical laptop
/ docking station?

Although I'm not thrilled by the idea of my drivers side puddle lamp having
it's own [IP] address!

~~~
jaclaz
AFAIK systems "bus based" are very similar, even for home/office electric
cabling.

In the home/office "domotic" ones there are usually two couples of wires, two
are the mains (poass-through) and two are "signal", every device is connected
to both.

The closest thing in typical networks is - I believe - PoE:
[https://en.wikipedia.org/wiki/Power_over_Ethernet](https://en.wikipedia.org/wiki/Power_over_Ethernet)

In automotive, normally the frame is 0V or "ground" and you need only a single
(big) wire with +12 V and the signal cable/wires.

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karmakaze
Tesla's big advantage is that they're not just building autos, they're
redefining how they get built. It's not about the car, it's about the machines
that make them and the interfaces between them. Effectively, the car is built
using an electromechanical design language (DSL) specialized for automated
manufacturing.

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ummm32
> ts unbelievable how much code does not react properly on Communications
> failures / init / lag.

I think this is the main reason those we do some kind of engineering work have
jobs.

Those issues are prevalent in anything built with some constraint in time
and/or money, that would be just almost everything built and in production on
Earth.

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sschueller
This is just Tesla claming they invented something like when Apple does the
same thing for something that others have been doing for a while. It's PR.

