Investor Engineering Discussions

[JRP3]

That efficiency is only at a particular operating region though. Expanding the zone would give more improvement.

Only if it were in the normal operating region of the vehicle. Meaning expanding the efficiency range to RPMs not normally seen would have little impact on real world range.

 

[JRP3]

In electrical motor design the armature and rotor always designed with the minimum air gap that is practical for efficiency reasons. If that air gap can be reduced by a carbon sleeve that limits expansion there should be efficiency gains through the entire rpm/torque range of the motor but the gains would taper off as rotor speeds increased because this is the realm that rotor expansion would have reduced the air gap anyway.

One thing I'm not clear on is how replacing some of the air gap distance with carbon fiber does anything other than preventing expansion at higher speeds. Say you have rotor diameter X and air gap distance of Y, you add Y/2 worth of carbon fiber leaving Y/2 air gap but the active rotor material size is still the same distance away from the stator. It could be as you say that the CF allows tighter low speed tolerances that more than make up the difference in thickness of the CF. Or it could be magnetically doped CF. Might also allow the magnets to be installed closer to the edge of the rotor.

 

[mongo]

One thing I'm not clear on is how replacing some of the air gap distance with carbon fiber does anything other than preventing expansion at higher speeds. Say you have rotor diameter X and air gap distance of Y, you add Y/2 worth of carbon fiber leaving Y/2 air gap but the active rotor material size is still the same distance away from the stator. It could be as you say that the CF allows tighter low speed tolerances that more than make up the difference in thickness of the CF. Or it could be magnetically doped CF. Might also allow the magnets to be installed closer to the edge of the rotor.

Replacing with CF reduces rotor expansion at higher RPM. CF allows for smaller air gap which probably results in smaller rotor to stator distance even including the CF thickness.

 

[mongo]

https://twitter.com/x/status/1404128430585618433

Main advantage of this is a much stronger EM field compared with a rotor that is held together by metal (usually high strength steel). Other advantage is that rotor can go to higher RPM, as carbon sleeve (mostly) stops copper rotor from expanding due to radial acceleration.

 

[JRP3]

Sandy likes the front MachE motor more than the rear and talks about some of the differences between wound wire and hairpin windings

 

[mongo]

AI day. WOW. I watched the entire presentation and will watch it again. 1,000,000,000,,000,000,000 calculations/second is not comprehensible. Some good points made here. Firefighting robots with boring tunnel equipment might help fight the current barrage of wildfires with some sparked by ICE vehicle's catalytic converters.
I still can't figure out how they can get billions of transistors on a tiny surface area.
The heat issue might be solved it they put DOJO in outer-space -270 degrees C. Satellites(SpaceX) with DOJO communicating with Teslas and semis might be quite amazing.
Basic income is coming but what will people do with all their spare time. Art, music, farming, etc.
SP is funny.

Space is 'cold' but more critcally, it's a vacuum. You don't get convective or conductive cooling like you would with cold air or fluid. Instead, it is all radiative cooling which is proportional to the object's temperature raised to the fouth power. For the 15kW dissipation per module at a normal chip temperature, it would need huge radiators.

 

[winfield100]

Space is 'cold' but more critcally, it's a vacuum. You don't get convective or conductive cooling like you would with cold air or fluid. Instead, it is all radiative cooling which is proportional to the object's temperature raised to the fouth power. For the 15kW dissipation per module at a normal chip temperature, it would need huge radiators.

perfect for a Stirling engine!

 

[JRP3]

Rich does a bit of exploratory disassembly on a new Raven. Finds some unfinished items and some oil leaks but is impressed overall.
Starts around the 4 min mark

 

[CorneliusXX]

It sounds like Gali has heard a more recent rumour than the Q1 earnings call that Tesla is still having problems with the 4680 calender rolls still getting dented over time as part of the DBE process. Berlin and Austin both to start production with 2170s.

Some good news is that some 4680s have already gone into energy products - so the new cell is getting real world testing.

 

[mongo]

It sounds like Gali has heard a more recent rumour than the Q1 earnings call that Tesla is still having problems with the 4680 calender rolls still getting dented over time as part of the DBE process. Berlin and Austin both to start production with 2170s.

Some good news is that some 4680s have already gone into energy products - so the new cell is getting real world testing.

Did you mean more recent than the Q2 earnings call from a month ago?
Tesla (TSLA) Q2 2021 Earnings Call Transcript | The Motley Fool

Elon Musk -- Chief Executive Officer


Really, this is not -- we'll definitely make the 4680 reliable enough for vehicles, and we, I think, are at the point where, in limited volume, it is reliable enough for vehicles. Again, going back to limited production is easy, prototype production is easy but high-volume production is hard. There are a number of challenges in transitioning from sort of small-scale production to a large volume production. And not to get too much into the weeds of things, but right now, we have a challenge with basically what's called calendaring, or basically squashing the cathode material to a particular height.

So it just goes through these rollers and gets squashed like pizza dough, basically, but very hard pizza dough. And it's causing -- it's denting the calendar rolls. This is not something that happened when the calendar rolls were smaller, but it is happening when the calendar rolls were bigger. So it's just like -- we were like, OK, we weren't expecting that.
Andrew Baglino -- Senior Vice President, Powertrain and Energy Engineering

Yeah. It's not like a science problem, it's an engineering problem.

Elon Musk -- Chief Executive Officer

Yeah.
Andrew Baglino -- Senior Vice President, Powertrain and Energy Engineering

It's not a question of if. It's a question of when.

Elon Musk -- Chief Executive Officer

Yeah.
Andrew Baglino -- Senior Vice President, Powertrain and Energy Engineering

And the team is 100% focused on resolving these limiting processes as quickly as possible.

Elon Musk -- Chief Executive Officer

Exactly.
Andrew Baglino -- Senior Vice President, Powertrain and Energy Engineering

On the reliability side, as Elon mentioned, we have successfully validated performance and the lifetime durability of the 4680 cells produced in Kato, and we're continuing ongoing verification of that reliability. We're actually accruing over one million equivalent miles on our cells that we produce every month. In our testing activities, the focus on that is very clear. We want high-quality cells for all of our customers.


And yeah, we're just focused on the unlucky limiting steps in the facility. And with the engineers focused on those few steps remaining, we're going to break through as fast as possible.
Elon Musk -- Chief Executive Officer

Meantime, we have a massive amount of equipment on order and arriving, for the high-volume cell production in Austin and Berlin. But obviously, given what we've learned with the pilot plant, which is in Fremont, which is really quite a big plant by most standards, we will have to modify a bunch of that equipment. So it won't be able to start immediately. But it seems like -- Andrew, correct me if I'm wrong, but we think, most likely, we will hit an annualized rate of 100-gigawatt hours a year, sometime next year.
Andrew Baglino -- Senior Vice President, Powertrain and Energy Engineering


We'll have all the equipment installed to accomplish 100-gigawatt hours, and it's possible that by the end of the year, we will be at an annualized rate of 100-gigawatt hours by the end of the year.
Elon Musk -- Chief Executive Officer

Yeah, I mean my guess is more likely than not, above 50% of reaching 100-gigawatt hours a year by the end of next year on the annualized rate, something like that.
Andrew Baglino -- Senior Vice President, Powertrain and Energy Engineering


Yup.
Elon Musk -- Chief Executive Officer

It could shift by a little bit, but as Drew mentioned, nothing fundamental, just a lot of work.
Andrew Baglino -- Senior Vice President, Powertrain and Energy Engineering


Yeah. And even to the large roller question, Elon, right. Like on the anode side, the large rollers work great, no concerns. And so we're just learning as we go.

And the nice thing about having that facility on a fast-track like we had it, and we talked about it at battery day, was really de-risking the big factories here. And, yes, we've done and we've learned a lot. And with each successive iteration, the ramp-up and the equipment installation will be faster and more safe.

 

[MC3OZ]

It is hard to tell if Galli has any solid new info.

At Austin cell production might be lacking raw materials Peidmont Lithium? was held up on their mine approval.
Is the 4680 production ramp behind schedule? Probably.

 

[JRP3]

Chinese battery maker says it's ready to produce cobalt-free EV power packs at scale

A Chinese company called SVOLT claims it’s ready to start producing a cobalt-free battery at scale.

finance.yahoo.com

 

[mongo]

Level 2 ("hands off"): The automated system takes full control of the vehicle: accelerating, braking, and steering. The driver must monitor the driving and be prepared to intervene immediately at any time if the automated system fails to respond properly.

Wikipedia is wrong by addition, Level 2 is not by definition "hands off". That would be level 3 (although this term is not used in J3016). Further, one cannot intervene immediately if hands are off the wheel.

The SAE view on intervention:

It should be noted, however, that crash avoidance features, including intervention-type active safety systems, may be included in vehicles equipped with driving automation systems at any level. For automated driving system (ADS) features (i.e., Levels 3 to 5) that perform the complete DDT, crash mitigation and avoidance capability is part of ADS functionality (see also 8.13).

Level 2 could include emergency vehicle avoidance, but it is not required.

So I think NHTSA is looking to see whether the claims about what people say Tesla tells drivers about capabilities is accurate. (ie is Tesla advertising current existence of features it does not have (in a reliable state)).

 

[Artful Dodger]

Wikipedia is wrong by addition, Level 2 is not by definition "hands off". That would be level 3 (although this term is not used in J3016). Further, one cannot intervene immediately if hands are off the wheel.

The SAE view on intervention:

Level 2 could include emergency vehicle avoidance, but it is not required.

So I think NHTSA is looking to see whether the claims about what people say Tesla tells drivers about capabilities is accurate. (ie is Tesla advertising current existence of features it does not have (in a reliable state)).

You're certainly right** about wikipedia not being authoritative on SAE self-driving levels, and I did consider diving into what the NHTSA actually uses for regulations, but my main concern with the whole process lies outside the regulations. Nontheless, here's the NHTSA definition of Level 2:

Level 2

An advanced driver assistance system (ADAS) on the vehicle can itself actually control both steering and braking/accelerating simultaneously under some circumstances. The human driver must continue to pay full attention (“monitor the driving environment”) at all times and perform the rest of the driving task.

Seeing the NHTSA apply their regulations in an uneven way (where established auto-majors are given a pass, or no scrutiny at all, while Tesla is being singled out for scrutiny, mostly because of constant, slanted media converage) does not pass the sniff test. It is all too likely that the political process has subverted the regulatory process for the financial gains of Tesla competitors and opponents.

Seems NHTSA doesn't think Autopilot is Level 2 because certain of the Press pretend ignorance of what that means? Or that there is no difference between Autopilot and FSD? Or that levels of autonomous driving capability don't matter whenever Wall $treet needs a break?

I'd like to see any evidence that the NHTSA has pursued this level of reporting from any other manufacturer. To me, this has all the appearance of a vendetta, wrapped in a witch-hunt, covering up a campaign against Tesla, with the purpose of limiting the progress they are making.

Worse of all, the NHTSA does not appear to have the greater "Public Safety" in mind, or their 11-page letter to Tesla would have mentioned how the mountains of data they seek could be used to demonstrate the relative safety of autopilot vs human drivers. Instead, the data they seek seems designed to provide for a fishing expedition. This should go to court, IMO.

Meanwhile, NHTSA has chosen to investigate a particular scenario (avoiding emergency vehicles) where Tesla Autopilot is being scrutinized for capabilities that are NOT part of its feature set. This effort can't end well, but it will play out in the public stage for months and years to come, which may be the larger goal (to faciliate the propagation of FUD).

**Thanks again for your steady vigilance on regulatory and procedural matters. This is really the nuts'n'bolts that governs progress in technology, and I want to give you credit you for your continued steady efforts.

Much appreciated.

 

[mongo]

You're certainly right** about wikipedia not being authoritative on SAE self-driving levels, and I did consider diving into what the NHTSA actually uses for regulations, but my main concern with the whole process lies outside the regulations. Nontheless, here's the NHTSA definition of Level 2:



Seeing the NHTSA apply their regulations in an uneven way (where established auto-majors are given a pass, or no scrutiny at all, while Tesla is being singled out for scrutiny, mostly because of constant, slanted media converage) does not pass the sniff test. It is all too likely that the political process has subverted the regulatory process for the financial gains of Tesla competitors and opponents.

Seems NHTSA doesn't think Autopilot is Level 2 because certain of the Press pretend ignorance of what that means? Or that there is no difference between Autopilot and FSD? Or that levels of autonomous driving capability don't matter whenever Wall $treet needs a break?

I'd like to see any evidence that the NHTSA has pursued this level of reporting from any other manufacturer. To me, this has all the appearance of a vendetta, wrapped in a witch-hunt, covering up a campaign against Tesla, with the purpose of limiting the progress they are making.

Worse of all, the NHTSA does not appear to have the greater "Public Safety" in mind, or their 11-page letter to Tesla would have mentioned how the mountains of data they seek could be used to demonstrate the relative safety of autopilot vs human drivers. Instead, the data they seek seems designed to provide for a fishing expedition. This should go to court, IMO.

Meanwhile, NHTSA has chosen to investigate a particular scenario (avoiding emergency vehicles) where Tesla Autopilot is being scrutinized for capabilities that are NOT part of its feature set. This effort can't end well, but it will play out in the public stage for months and years to come, which may be the larger goal (to faciliate the propagation of FUD).

**Thanks again for your steady vigilance on regulatory and procedural matters. This is really the nuts'n'bolts that governs progress in technology, and I want to give you credit you for your continued steady efforts.

Much appreciated.

I may be overly optimistic here, but the preliminary investigation could be a good thing, if NHTSA finds (and reports publicly) that Tesla is not misleading customers and that Autopilot increases safety (couod even set the bar for performance). At this point, they are only in the information gathering stage, so it seems too soon to glean intentions.

The full spec is available for free (surprising for SAE) from ANSI. (I only skimmed it at this point)

 

[mongo]

So tesla actually package their own PCB in house? We are not talking about design here, we are talking about tesla getting the chip from samsung or whoever and then prints them onto a PCB in house vs outsourcing it to China like in this video?

Ah, I see what you mean, no, Tesla doesn't do that, but to keep this thread on subject (at least kinda), Tesla does all the work above the chip to hand off to a fab which **just** manufactures the board, Tesla owns all the rest.

Your confusion is understandable, I made sure to reread the post before my response to ensure that was not was written:

Tesla does not make their own boards except the FSD board (and even then they don't exactly make the board..they just made the board design and the third party fabs everything). Everything else is third party like the infotainment board, and all the micro controller board.

This statement specifically says that only the FSD board was designed in house, and then fabed by third party. Thus implying all others are designed out of house. The last line directly states the other boards are non-Tesla designed.

My Tier 1 former employer did PCB assembly inhouse, but not raw PCBs. Cost benefit is not there.

This thread is good for engineering stuffs.

 

[MC3OZ]

This statement specifically says that only the FSD board was designed in house, and then fabed by third party.

This stuff can be done by fairly small companies...

A worked for a very small company that designed boards... (mainly outsourced to a guy who used to design Nokia phones.)

Boards when then baked by a company, not sure what size... but not overly large... (This was back in the 1980s, boards baked in an oven are probably an older generation of tech..)

Then we sourced all components, and outsourced a run at a factory with pick-and-place robots.. from the deception I was given, it seemed that that factory that put the components on the boards, had around 30-50 employees.

This pick-and-place robot factory was in Australia with a white male Australian boss and a workforce of mostly Chinese women, my boss mentioned when a woman needed to go on maternity leave, the factory workers arranged a replacement,,,

All of this was in the 1980s in Australia, and I think mostly done by very small companies...

We didn't design any chips, standard chips, could do what we needed...

I was on the software side ... not intimately involved with the hardware.

Whether Tesla will do all this stuff, depends only of whether they need to, for any reason, if they need to do it, it can be done...

 

[mongo]

OT: Ouch! All elements heavier than iron are made in stars. Iron is the heaviest element to be made by fusion exothermally

Elon was correct in that Iron is the last element (heaviest) made in a star (versus by a star (encompassing post star life cycle)) in any significant quantities. Four heavier elements do form though: Ask Ethan: Can Normal Stars Make Elements Heavier (And Less Stable) Than Iron?

Elements higher than Hydrogen up to and including iron (*excluding lithium, beryllium and boron) are created in stars by fusion, but iron creation is endothermic [per Futurism article which may be incorrect, regardless iron is too stable too fuse], and the end of the line for a star's core. What Happens When Stars Produce Iron?
Stellar Death
Heavier elements are generated when stars go out (no longer a star) and generate nova or supernova.
How to Make an Element

*Lithium, beryllium and boron are created by cosmic ray spallation of heavier elements. Cosmic ray spallation - Wikipedia

 

[JustMe]

Elon was correct in that Iron is the last element (heaviest) made in a star (versus by a star (encompassing post star life cycle)) in any significant quantities. Four heavier elements do form though: Ask Ethan: Can Normal Stars Make Elements Heavier (And Less Stable) Than Iron?

Elements higher than Hydrogen up to and including iron (*excluding lithium, beryllium and boron) are created in stars by fusion, but iron creation is endothermic, and the end of the line for a star's core. What Happens When Stars Produce Iron?
Stellar Death
Heavier elements are generated when stars go out (no longer a star) and generate nova or supernova.
How to Make an Element

*Lithium, beryllium and boron are created by cosmic ray spallation of heavier elements. Cosmic ray spallation - Wikipedia

This is not correct. “Iron creation” is not endothermic, it is exothermic. However fusion of elements heavier than iron is endothermic. Elements heavier than iron are also made in stars by neutron capture in the red giant phase. S-process

“Synthesis of the Elements in Stars”
E. Margaret Burbidge, G. R. Burbidge, William A. Fowler, and F. Hoyle
Rev. Mod. Phys. 29, 547 – 1 October 1957

 

[mongo]

This is not correct. “Iron creation” is not endothermic, it is exothermic. However fusion of elements heavier than iron is endothermic. Elements heavier than iron are also made by neutron capture in the red giant phase. S-process

“Synthesis of the Elements in Stars”
E. Margaret Burbidge, G. R. Burbidge, William A. Fowler, and F. Hoyle
Rev. Mod. Phys. 29, 547 – 1 October 1957

Yeah, I edited the endothermic part while you were writing.
Is it correct to say that iron is the end of the road for the average star's progression even if the s-process does result in other elements (mostly in AGB stars that are seeded with iron)?