That’s an old story.
It actually takes quite a rapid acceleration burst to keep the hand off the dashboard.
Very few sports cars can do it. The reason the Tesla could do it was the instantaneous pull of the electric motor.
Short of a top-fuel dragster, even granny can touch the dashboard of an accelerating high-performance car. The fastest street cars accelerate at just beyond 1 G, which pretty much anyone can do if they can lift their arms in bed.
The key to the story is that the passenger is surprised. By the time they realize they need to make an extra effort (a few seconds later), the car is already at 60 mph or whatever.
I’m sure Shelby managed the effort with a bit of verbal patter, misdirection, and distraction. With an electric, that comes for free. It’s not just the torque, but the fact that it comes on instantaneously and with no warning. There’s no launch mode, no revving the engine before you drop the clutch, etc.
And at any rate, the point of the story isn’t that no one’s done it before; it’s that they did it in an EV. Gas racecars have existed forever, so no one’s surprised at their existence. But most people had still been thinking of EVs as golf carts and slow weirdmobiles before that point.
what they’re referring to is the launch of the car and not the acceleration down the track. The first second when the car moves from zero to whatever. I’ve been in street cars that pin you to the seat off the line. A Tesla with 2 motors has the advantage of all wheel drive and a lot of torque.
The sky’s the limit on future sports cars because it will be very easy to install (2) 750 hp motors at a fraction of the cost of the exotic sports cars of today.
There’s no difference. Even at a standstill, peak acceleration is limited by tires and other factors. It’s not much more than 1 G even on the fastest street cars. Dragsters achieve more by having tires that are more like glue than rubber (and absurd amounts of power).
If you tell your passenger to put their finger on the dashboard, and push on the dash as hard as they can stand, they will have no problem keeping it there on a launch. “Pinning” only comes from the surprise of the launch, and to some extent the finite time it takes the muscles to tense up from a relaxed position.
We liked our toys in my youth. We had cars that would pull the front end off the ground. the pinning comes from not sitting back in he seat. You WILL get slammed back into the seat. It’s like trying to do a sit up with someone sitting on your chest.
No; it’s like doing a fairly normal sit-up.
I’m not saying you don’t get slammed back in your seat. I’m just saying that the level of peak acceleration isn’t the issue. In fact, it’s the change in acceleration: the aptly-named jerk.
Jerk feels unpleasant because it means you have to transition your muscles from an untensed to tensed state (or vice-versa). It happens even for very low accelerations. You get bounced around because this tensing takes time, and in a fast enough car you may have accelerated to the desired speed in the meantime.
Jerk happens on braking, too. Have you noticed that some drivers can brake smoothly and some can’t? The difference is usually that smooth drivers know to let up on the brake pedal just as they’re coming to a halt. This limits the peak jerk by smoothing out the transition between a finite deceleration and zero deceleration (i.e., the car has come to a stop).
Exact same thing. Watch people’s heads. If they bounce forward when you come to a stop, you aren’t limiting jerk.
Gas cars tend to limit jerk on acceleration through the action of their clutch or torque converter. With enough power, though, you can still get to pretty high levels. And of course an EV can reach “infinite” jerk (of course, it’s still limited by tire flex, axle twist, and other effects, but it’s very high nevertheless).
No doubt. Manufacturing is a modern wonder. Unless your house and furniture consists solely of hand-hewn wood with tools made from meteorite iron, probably everything within arms reach took an unbelievable chain of manufacturing technology to make its way to you. The most visible thing on my desk is–a 10-pack of laser diodes that I bought for $5. Every aspect of them, from the crystalline semiconductor material to the fiberglass PCB to the metal casing is a marvel. And they’re just these crappy things that cost 50 cents, and are no more than a subcomponent of a subcomponent of a subcomponent for a typical product.
As for parallelism, what you say is certainly true. The line is itself also a parallel operation, being broken into equal-time stages that are worked on simultaneously (in the computer industry, this is called pipelining). There are many types of parallelization that work at multiple levels–what you’re describing is a kind of unit-level parallelization.
It’s not surprising that some types of parallelization would be more or less effective for final assembly, and it’s interesting to think about the reasons. Some of the weighting factors may change over time, so it’s possible that different styles will become more optimal at some future point.
or maybe- just maybe- everyone builds cars the same way because after 100+ years of building cars, they’ve found the best way to do it?
That’s ridiculous. There have been multiple revolutions in manufacturing over that time, among them the Japanese revolution started by Deming. Detroit had to be dragged kicking and screaming into the modern era. The NUMMI plant itself was a collaboration designed to teach GM how to not build pieces of shit.
I see no reason to believe the modern era is anything special; that we just happen to have hit on the optimal way to manufacture cars until the end of time. Technology changes. The environment changes. Attitudes change. The only constant is resistance to change.
That’s not to say that anyone has hit on the next big revolution yet. Will 3D printing make an impact past the design stage? No one can say yet. Extremely powerful computer vision is another factor. Or applying deep learning/AI to robot or even plant control. There are lots of new possibilities and simply claiming that the current way is the best way because it evolved over a century (not really accurate in the first place) is nonsense.
3D printed parts are already underway:
https://www.3dprintingmedia.network/automotive-3d-printing-production-coming-2018/
But surely you have to agree that the evidence so far suggests quite strongly that Tesla is not creating a new, more efficient way to build cars.
3D printed parts are definitely a thing at the small scale. SpaceX prints rocket engine parts in Inconel (a superalloy). Tesla is probably using it for their main contactor on ludicrous mode cars. However, it’s still too slow to replace stamping and machining–for the moment. Could be that it’ll always be too slow; could be that it ends up being used for a small number of specialized and hard-to-machine parts; could be that it virtually takes over some types of manufacturing. Hard to say right now, but it’ll be interesting to watch.
They have certainly not yet created a new, more efficient way of making cars, and I don’t think I ever claimed otherwise. There is some evidence that the Model Y will make a big step in that direction–specifically regarding the wiring harness, which they intend to reduce in length by a factor of 10. We’ll see if they can pull it off.
The Model 3 was a big step forward in manufacturability–for Tesla. Which puts it, probably, roughly on par with existing manufacturers. Obviously, they’re still working the kinks out, but they’re already doing better than the Roadster/S/X at this stage.
Contrary to jz’s suggestion, I don’t think the existing manufacturers are holding still, either. So Tesla will have to not just beat their own target, but where the others will be a few years from now. Regardless, I think they’ll have something to contribute to the industry, even if it isn’t quite a revolution.
that is not what I said. and you know that is not what I said.
Except he’s right, by today’s measurables. It took time for everyone to get here, but from 10,000 feet, we build cars the same way. Particular processes to build components are different, but in the end, if you walk into any final assembly shop from Tesla, Ford, Audi, Great Wall Motors, you’ll be right at home. Final assembly is the great integration area, and modern logistics pretty much dictates that we all work the same. This isn’t automotive science, but logistics science.
The innovations that distinguish us are what people typically think of as the boring bits, or the parallelized bits that we mentioned up-thread. When normal people want to see a car being built, they want to see tires being installed, seats attached, doors hung, etc. In most people’s minds, that’s “building” the car. In the areas where we differ, there’s a lot of engineering investment. A lot of this effort is one-upmanship, but also cost cutting, durability, warranty cost reduction, and other efforts that are meant to give the customer a better product. Everyone hangs the door the same, but Audi might laser weld the inner and outer panels together in order to avoid hem flange corrosion. This is pretty innovative, but in the end, it’s just a door being hung onto the body. The way the car is assembled is more or less identical to FCA’s process.
We really have to move the conversation away from manufacturing cars to manufacturing car components if we want to distinguish anyone, and even there, process-wise, there are a lot more similarities than differences.
Short of precipitating finished products out of a white room filled with an exotic gas consisting of self-assembling molecules, there’s not a whole lot of room for groundbreaking improvement in the assembly process.
what rustled my jimmies about that comment was claiming I said everyone is standing still. Which isn’t what I said. Advancements in design and manufacturing techniques are continually happening. it’s just that when someone comes up with something new, barring any patents or other protected IP it pretty quickly starts spreading through the industry. for ex; several years ago VW was making noises about how their modular MQB and MLB will reduce engineering cost and complexity. Now other automakers (cough) are following suit.
meanwhile, it was only last year when Elon had the brilliant idea to base the Model Y on the existing Model 3 platform instead of doing yet another one from scratch.
Tesla is opening a new showroom and service facility a few miles from my house. The article says “may open” but also that they’ve signed a 10 year lease. This will make service convenient, if I ever get my car. My reservation is listed as “late 2018” and the Tesla facility is listed as “near future.” I wonder which will happen first.
Go back and look at post #788. Dr. Strangelove made a rather generic comment about how different manufacturing processes may become optimal at a later point, given technological advances.
Kinda difficult to argue with that unless you’ve concluded that the major auto manufacturers have already achieved perfection, and there is no further room for improvement for anyone, beyond polishing that last 1%. And with that context its difficult to read your response of
otherwise. Maybe that’s not what you meant, but that’s certainly how it came across.
Thanks, YamatoTwinkie. I certainly didn’t see any other way to read the comment.
I agree with Balthisar in that short of nanomanufacturing or whatever, we aren’t going to be seeing extreme changes at the 10k foot level. But that’s a pretty high bar to reach. Again going back to the Japanese revolution, that wasn’t even a change in the factory, aside from perhaps some ergonomic improvements here and there. You could not have spotted a difference from photographs of two factories. It was a change in management style, which nevertheless had an outsized effect on the quality of the products produced.
Most improvements in manufacturing are of this nature–something that you couldn’t even see unless you were looking closely. One of Ford’s big innovations was having interchangeable parts (as applied to automotive). That is, all the parts were machined precisely enough that they didn’t have to be either paired with a particular machine or basically hammered into place. If you were watching, the only thing you’d notice between the two factories is that one of them seems to require a lot less effort fitting the pieces together. They’re much more productive but the reasons why are sorta hidden.
To my eyes, one ongoing lesson is that to reduce waste, you must first identify it. And that gets kinda tricky because if you’ve been doing something for long enough, it can be hard to distinguish wasteful steps from necessary parts of the process. A station which is idle because a sunroof-less car is passing through–or only takes 15 seconds instead of the allowed 25 because it had 6-speaker sound instead of 12–is a waste. That doesn’t mean that the waste can be captured with the current level of technology, but it means it’s at least on the table.
I do actually expect deep learning to make significant improvements in robot control. For instance, in one video I saw a while back a robot was installing a dashboard. The dash is long and had to be fed in from one door opening, which meant there was a long moment arm for the dash+robot. So there was a lot of bounce in its movements, and after every step the robot paused a bit to let things settle. It was reminiscent of an elderly person moving around–they lack the confidence and control to blend movements together, the way a normal person would. A robot that could self-optimize with a learning system, using sensor feedback, could have much more fluid movements and no need to pause at every step or even divide the procedure into individual steps.
This isn’t necessarily revolutionary in itself, but it does change the relative cost and performance of robots vs. humans. So at some point, it does become advantageous to have a “lights out” factory, which is pretty revolutionary. If and when this will happen I’ve no idea, but these are the kinds of weighting factors I’m talking about.
FWIW, I thought jz’s comment and intent was perfectly clear and pretty much impossible to argue with.