71–80 of 107 posts
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"Loud speaker" surprises me. Are you sure they don't use semiconductors for amplification?
Speakers? Definitely not. The amplifier will, but not the loudspeakers. That's basically a magnet, a coil, and a paper cone.
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SpaceX is also using commodity hardware, but they duplicate it 3x with majority vote for error correction.
do you happen to have pointers evidencing this handy? IS this also true for Dragon?
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"Loud speaker" surprises me. Are you sure they don't use semiconductors for amplification?
Speakers? Definitely not. The amplifier will, but not the loudspeakers. That's basically a magnet, a coil, and a paper cone.
[1] https://www.amazon.co.uk/AmazonBasics-Computer-Speakers-Desk...
This article does a good job outlining why these systems can't just be replaced with a Raspberry Pi or an Arduino: Durability. At one point I was interested in replacing the ECU in my old '88 Suburban. The ECU is probably the only "real" bit of electronics in the whole vehicle. And yet after almost 35 years it's still doing fine. The Arduino based ECU I was looking into, as it turns out, is a great hobby project, but…
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High-order crossover filter?
Well, if we're going there, we might as well just delve into the whole Active Speaker thing and get into the amplifiers. But a basic speaker (driver) that's been around for decades is essentially a small linear motor: one moving part and very simple in operation.
All their engineering and supply structures have evolved from mass producing mechanical marvels which happen to have a few electrical and electronic E/E components, marvels and components which are hard to manufacture but simple to integrate ("plug together", essentially).
At the core, their thinking goes "Creating components is expensive. Putting components together is cheap. Also minimize prototype scrap with extensive planning and scrupulous list checking processes. If parts don't work together you didn't plan well enough."
And that leads to a culture that is the exact opposite of CI/CD, fail early, fail often, rebase or reintegrate continuously.
Thus in the automotive SPICE and six sigma world it takes 2-3 years to replace an ECU with another one with sufficiently similar specs.
Also, they prioritize "economies of scale" over flexibility and time to market.
For example a "gateway controller", a router and switch, routing and switching between ethernet and CAN, with some spare CPU cycles for centralized functions? 2-3 years. Now let's say you need 3 million of these devices per year (Volkswagen group, Toyota, Stellantis each make ~10 million vehicles y/y), and you'll produce cars with that same device for 5 years? Then cost savings of 10$ per device are equal to 150 Mio bucks. As a supplier you'll happily put 20 people on saving those 10 bucks on the "bill of materials" --- not adding cool features, no, saving some RAM, CPU, ... the boring and non-innovative side of "economies of scale"
Now the device is cheaper but maxed out. So your OEM won't ship new functions. the OEM is also later to market. And the OEM can't replace the part as easily because the spare would have to be as damn dirt cheap as the original. Not alone would you have to redo all these micro optimizations --- the savings from the previous design wouldn't materialize against the lower volume any more.
And that is, in a nutshell, imnsho, why automotive asks for more of the old parts instead of switching to a new board design with a next-gen CPU...
To summarize: automotive deals time to market and flexibility for "economies of scale" and "automotive grade quality processes".
Contrast that to an OEM who thinks like a software CEO... the software CEO understands that the secret to high quality is in CI/CD with outstanding test and validation pipelines. You seek to change any part of your system just at marginal cost. And then you can replace some ECU within 6 months.
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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.
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. Yo…
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 pur…
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SpaceX is also using commodity hardware, but they duplicate it 3x with majority vote for error correction.
do you happen to have pointers evidencing this handy? IS this also true for Dragon?
What devices are left that are fairly normal (that normal people might interact with in a given week), mechanical or electromechanical, have at least modest complexity, and have no microchips? Locks? Guns? What else? EDIT: perhaps an extra requirement that it's fairly durable, i.e. easily lasts ten years of normal use. EDIT2: maybe it should also fit the requirement that it's a current model in production and that yo…
I'm still mesmerized by microwave ovens. Sure, all of them now come with a chip, but that part is guaranteed 100% shit (I mean who the fuck designs these unergonomic monsters anyway!?) But the magnetron in them is complex, has to be machined to a high precision, yet they are a pretty old piece of completely analog technology.
https://www.lg.com/us/cooking-appliances/lg-LMC0975ST-counte...