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Re:Tesla shares 48V architecture with other automakers to mo... by hinkley on Thursday December 07, 2023 @05:09PM (#38562504)
Tesla didn’t invent 48 volts either. The EV and hybrid electric world were talking about 48 volts when Musk still worked at PayPal, if not earlier.

One of the examples pulled out at that time was that you could shave a couple pounds of copper off the alternator by running it at 4x the voltage. Much thinner wires.

Re:Tesla shares 48V architecture with other automakers to mo... by jsight on Thursday December 07, 2023 @06:02PM (#38562999)
Tesla's greatest innovation is simply leadership. Everyone knew castings were the way to go, but noone did it. Now people like Volvo are doing them, and I expect a lot of others to do it as well.

Everyone knew that 48V would be a big benefit, but noone did it.

TBH, in a few years, we may be saying similar things about drive-by-wire without a mechanical backup. But it is too early to say definitively.

Re:Tesla shares 48V architecture with other automakers to mo... by Turskarama on Thursday December 07, 2023 @08:13PM (#38564144)
The mechanical backup for a drive-by-wire system is different to all those other things in that it's a critical safety issue. If _anything at all_ happens to the electronics while driving then it's important that you can stop the vehicle safely. That mandates manual brakes and steering, even if they're barely effective at all without power it's a lot better than nothing.
Re:Tesla shares 48V architecture with other automakers to mo... by dreamcompiler on Thursday December 07, 2023 @08:30PM (#38564271)
The cybertruck has two separate steering motors for redundancy. Passenger jets have been doing "x-by-wire" for decades. Properly engineered it's as reliable as mechanical linkage.
Re:Tesla shares 48V architecture with other automakers to mo... by Turskarama on Thursday December 07, 2023 @09:32PM (#38564699)
Two motors is great and all, but that only provides motor redundancy and won't help if something happens to the electrical system.

Planes are fly by wire but that's because they literally have to be, no amount of gym time will let you move the rudder on a 737 by hand.

Re:Tesla shares 48V architecture with other automakers to mo... by masklinn on Friday December 08, 2023 @12:32AM (#38565771)
The 737 is not fly by wire.
Re:Tesla shares 48V architecture with other automakers to mo... by Turskarama on Friday December 08, 2023 @12:53AM (#38565864)
Ok fair enough, it is hydraulic assisted instead but for the point I'm trying to make it's essentially the same thing in so far as it requires power.
Re:Tesla shares 48V architecture with other automakers to mo... by jsight on Thursday December 07, 2023 @10:52PM (#38565237)
I tend to agree, TBH. People bring up fly-by-wire, but even that is simpler. AFAIK, those systems aren't variable ratio the way CT is. CT literally will have different steering ratios depending on the speed, so one steering wheel angle will have different effects on the actual steering angle depending upon the speed.

How will that work in the real world? Could there be bugs? Will people get used to it or will it lead to mistakes?

I'm looking forward to getting a chance to try it, TBH.

Re:Tesla shares 48V architecture with other automakers to mo... by hinkley on Friday December 08, 2023 @04:20AM (#38566970)
I hear it’s kind of a pain in the ass to do a front end alignment on the drive by wire systems.
Re:Tesla shares 48V architecture with other automakers to mo... by p_l on Thursday December 07, 2023 @06:11PM (#38563069)
What everyone was waiting for was for Italians to make the huge casting press so that castings could be done in mass production at automaker margins.
Re:Tesla shares 48V architecture with other automakers to mo... by jsight on Thursday December 07, 2023 @10:45PM (#38565186)
Despite Tesla's boastings, large casting machines have existed before. Automotive use is the new part.
Re:Tesla shares 48V architecture with other automakers to mo... by p_l on Friday December 08, 2023 @04:15AM (#38566941)
Essentially it was question casting of this size being automated at car maker scale. Bigger castings were integrated before on assembly lines, but at higher costs and complexity before Italians made the large mostly automated caster that Tesla called GigaPress (iirc) - it's essentially COTS factory equipment.
Re:Tesla shares 48V architecture with other automakers to mo... by panick21_ on Saturday December 09, 2023 @07:37PM (#38587773)
What's actually new and interesting here is the combination of size and speed. Sure casting existed, but for it to be the backbone of a super fast production line like that of a Model Y, they needed to do a lot of work.

Larger parts were often dipped into liquid, because air cooling resulted the part bending.

Tesla internal materials team worked on new alloys to improve this, while working in coordination with the machine manufacture to get up the cycle times.

And they are continuing to work with them. Tesla is using newer more advanced cooling systems in Texas then they did in the California factory. Because cooling is one of the limiting factors in Cycling these machines.

Re:Tesla shares 48V architecture with other automakers to mo... by panick21_ on Saturday December 09, 2023 @07:36PM (#38587768)
Except it was Tesla that went to the Italian casting press manufacturer and the made it a project together. Tesla asked for the biggest they had and asked for bigger and basically bought 5 years of machines, allowing them to do the necessary investment. And Tesla also used its own internal materials team to develop alloys to optimize the process to make it practical for high volume production lines like Model Y.
Re:Tesla shares 48V architecture with other automakers to mo... by CharlesW on Thursday December 07, 2023 @06:25PM (#38563209)
> Everyone knew castings were the way to go…

The jury's still out on whether gigacasting is courageous, or just moves costs from production (which will not be passed to consumers) to repairs (which will).

> Everyone knew that 48V would be a big benefit, but noone did it.

Audi did in 2016 with the SQ7 TDI, no?

Re:Tesla shares 48V architecture with other automakers to mo... by bagels on Thursday December 07, 2023 @07:27PM (#38563822)
Car A costs $5k less to manufacture than car B because it uses castings. Car A would be wiser to build because you can get better margins, or lower prices. It'll take a lot longer for buyers to catch on to the fact that the car costs a lot more to repair.
Re:Tesla shares 48V architecture with other automakers to mo... by biaachmonkie on Thursday December 07, 2023 @08:58PM (#38564471)
The question is really if the castings result in more cars being written off as total loss. Any collision severe enough to damage them would likely be severe enough to also total out a car without them as well.
Re:Tesla shares 48V architecture with other automakers to mo... by jsight on Thursday December 07, 2023 @10:49PM (#38565217)
TBH, the repairability concerns seem to be overstated so far. There are still conventional crash structures in front of and behind them. It takes a lot to damage the casting beyond repair.

You are right, though. The jury is still out in that they haven't really been used in the real world for long.

> Audi did in 2016 with the SQ7 TDI, no?

I didn't know about that one, but it was still a dual architecture. Going full 48V is a bit different, assuming Tesla really did that.

Re:Tesla shares 48V architecture with other automakers to mo... by hinkley on Friday December 08, 2023 @12:41PM (#38571760)
Clearly no MGB fans at Tesla. The unibody is cool unless you live somewhere with snow, and then rust doesn’t just make your car ugly, it makes it unsafe. And expensive to fix.

Which is why I was always more of a Triumph fan.

Re:Tesla shares 48V architecture with other automakers to mo... by phkahler on Thursday December 07, 2023 @10:31PM (#38565114)
>> Tesla's greatest innovation is simply leadership.

Totally correct. We were making 48v power steering systems 20 years ago for OEM development projects. They simply don't have the will/commitment/leadership to bring change like that to market.

Elon sets a direction and people go that way. I can imagine someone at GM listing all the obstacles as a reason they can't change, and Elon looking at them and saying "no, you're the obstacle" or something like that.

Re:Tesla shares 48V architecture with other automakers to mo... by DennisP on Thursday December 07, 2023 @07:40PM (#38563909)
Sure, people have been talking about 48 volts for the past 30 years. Somehow most automakers didn't actually manage to do it though.

Sandy Munro just did an interview with Musk, who said they hadn't done anything revolutionary, they just built the car up to general 21st century standards.

Re:Tesla shares 48V architecture with other automakers to mo... by dreamcompiler on Thursday December 07, 2023 @08:31PM (#38564279)
Re:Tesla shares 48V architecture with other automakers to mo... by grecy on Thursday December 07, 2023 @08:23PM (#38564214)
> The EV and hybrid electric world were talking about 48 volts when Musk still worked at PayPal, if not earlier.

You are confounding the two electrical systems in an EV or hybrid (or mild hybrid).

One is used to drive the wheels - these are very commonly 48V in a mild hybrid and something like 200V or 400V or 800V in an EV. This is only used to power the wheels - nothing else.

The other electrical system is used to power literally everything else. The infotainment system, heated seats, power windows, lights, powered seats, electric power steering, electric assist brakes, etc. This has always been 12V in every car ever ^ (ICE/hybrid/EV) (including every Tesla).

The Cybertruck is the first vehicle ever to move the 12V system to a 48V system.

^ Before about 1955 it was 6v. The move to 12v then was the last time it has changed.

Re:Tesla shares 48V architecture with other automakers to mo... by hinkley on Friday December 08, 2023 @04:29AM (#38567023)
I’m talking about the same thing. Pumps and compressors and electronics systems.
Re:Tesla shares 48V architecture with other automakers to mo... by grecy on Friday December 08, 2023 @05:22AM (#38567350)
You're talking about some of the things that would be on the accessory belt (serpentine belt) on an ICE, that need to keep spinning even when the ICE is off (power steering, A/C, etc.). That is a slightly more fancy engine start/stop.

You are not talking about high current devices like heated and cooled seats, defrosters, infotainment and audio amps, power windows, power seats, lights, etc. etc.