Roadster #1 on its way plus more

[TEG]

With PRNDx, Tesla might have to devise some sort of "parking lock" mechanism for the trans. When in "P" does it put some "pin" in the transmission gear so the car is "safe" parked on hills even without the handbrake applied?

I never realized that the 1 speed triggers a regulation for PRNDx. That kind of sucks (in a way) because it does present a bit of a different image for the car (being more like an auto).

My Lexus has an auto trans, but they did all they could to make it seem more like a manual. It has a Ferrari style chrome ball shift knob and has gear up/down buttons on the steering wheel for picking a gear (although it still always retains the choice to automatically use different gears from the one I selected... It just lets me give it a 'suggestion').

It will be interesting to see how Tesla handles the PRNDx requirement in terms of shifter/selector location, appearance and such.

 

[malcolm]

An Automatic Sports Car??

I never realized that the 1 speed triggers a regulation for PRNDx. That kind of sucks (in a way) because it does present a bit of a different image for the car (being more like an auto).

Oh Lord, yes.

Tesla have worked so hard to cultivate that sports car pedigree only to be forced to adopt an extremely un-sporty central console feature.

Less of a problem for Whitestar, but presumably they cannot justify continuing the two-speed transmission development programme for the Roadster alone, unless Elon is offended by the presence of PRNDx and is prepared to fund it.

 

[doug]

With PRNDx, Tesla might have to devise some sort of "parking lock" mechanism for the trans. When in "P" does it put some "pin" in the transmission gear so the car is "safe" parked on hills even without the handbrake applied?

That's a good question. I've seen plenty of people that only drive automatics and have no idea what the hand brake is for.

 

[Dogtown]

.. If you are willing to give up the rumble

What does it matter if it is more like an automatic? For decades car companies have been trying to get an auto that will out perform a manual transmission. One gear pretty much fixes that. I just hope they do it right and don't just leave the big stick in the middle. I have always thought the center consol was the weakest part of the design. Here is a chance to remedy that a little. Besides how many time to you power shifters really think you were gong to shift when the only shift point was at 65 mph?

 

[JRP3]

I have to agree that this seems much ado about nothing. Shifting is a requirement of an ICE to keep it in the power band, not so with an electric. This is a game changing automobile and people are worked about about the PRND shifter? I don't get it. If you need to shift gears to enjoy driving, drive an ICE.

 

[BlackbirdHighway]

Surprise, Surprise!

So, I go skiing for a week, and when I get back they've gone and redesigned my car.

I honestly don't know what to think about this. Being able to perform great with only one gear is certainly very cool, but I can't help thinking that with the extra power & torque and an appropriate two or three speed transmission, 0-60 in the low 3's could have been possible. I guess we shouldn't be that greedy. Plus, Tesla can always go that way when the time comes for a second generation Roadster, a few years down the road.

Maybe these new components have already been well tested as part of the Whitestar develpment, and this will really speed up production, or maybe there will be a lot of extra testing required, and maybe a few design tweaks, and only the first 100 cars will wind up getting produced in 2008. I really don't know, but I hope to have a better idea after the town hall meeting.

How do you all think this came about? I'm thinking they used some Roadster prototypes as test mules for some of the Whitestar components, and it worked so well that they suddenly realized this was a solution to the transmission issues.

Then again, I remember Zak mentioning back in December that
there were some interesting drivetrain improvements on the way. I thought he was talking about a Roadster 2.0, but he said no, more like a Roadster 1.5.

When you think about it, this is typical Silicon Valley, isn't it? Before I even get the product, there is already a service pack upgrade for it. :biggrin:

 

[malcolm]

My concern is only about the image of the new transmission controls. PRNDL is an odd thing to see in a sports car. I'd be more than happy to live with it, but if the Roadster is going up against the Porsches of this world, others may be more pernickety about it.

In terms of how it came about - it is a quick solve for gearbox durability and gear-change duration issues. No gear change is faster than no gears. (Can we now get below 3.9?) Torque delivery does not have to be limited or dampened to protect gear teeth while the cogs are swapped.

 

[BlackbirdHighway]

It's interesting how different people see things. I'm not at all concerned about how the PRNDL switch looks.

I remember before I bought my S2000, I went looking at various sports cars, many of them much more expensive. I could not believe how many so-called sports cars didn't even have the option of a manual transmission. It wasn't the look of the shifter that I was concerned about, it was the squishy feel of accelerating with a slushbox. That's one of the many things I found appealing with the S2000, they don't even offer the option of an automatic.

So does anyone have a clue - are these new motor and PEM components just now being developed specifically to address the transmission problem? If so, then I don't see how more than 100 cars are going to be produced this year. It's simply going to take too long to get through the normal cycles of testing, design tweaking, retesting, etc.

Or, were these new components already in the works, and now they have reached the point where they are the best solution to the transmission problem?

One speed may be a good fix, but I don't understand how you go so quickly from from one game plan to another. It wasn't that long ago that Elon and the gang were talking about two different vendors working in parallel on new transmissions.. These new guys were not going to start from scratch, but build on what was learned from the failures of the earlier efforts.

I guess Tesla just has higher confidence in motors than transmissions, which is somewhat understandable. But in the last town meeting, they sounded so confident in the new transmissions. Now it seems they weren't so confident after all, if they are willing to go with a different game plan right on the eve of production start up.

The car was supposed to be delivered last year, and now they are still changing the design of the drivetrain. IMHO, at this point, the one gear/two gear question should have been long settled.

 

[WarpedOne]

... But in the last town meeting, they sounded so confident in the new transmissions. Now it seems they weren't so confident after all, if they are willing to go with a different game plan right on the eve of production start up.

No, they weren't confident into the new transmission. They were confident at least one of the two major transmission companies will be able to harden the design. I guess neither of them did, they gave up or process would take too much time.

What would you do in such a situation? Bring in fifth and sixth transmission company and redesign the damn thing from scratch or use what you have on the other desk almost ready to use?

 

[Kardax]

So does anyone have a clue - are these new motor and PEM components just now being developed specifically to address the transmission problem? If so, then I don't see how more than 100 cars are going to be produced this year. It's simply going to take too long to get through the normal cycles of testing, design tweaking, retesting, etc.

Or, were these new components already in the works, and now they have reached the point where they are the best solution to the transmission problem?

All indications are that this new design with the liquid-cooled motor and single-speed transmission were being developed for the bigger, heavier WhiteStar. The transmission itself, if it could even be called that with a single gear, is apparently being designed by the same people that did the transmission for the Bugatti Veyron, so I would think a simple design like that should be well within their capability...

The decision to switch the whole drive train obviously carries a huge risk... but I guess Tesla determined it was less risky than waiting for a reliable two-speed transmission to be built.

Regardless, they're starting production with the older second-gear-only transmission that's been in use for a long time, and the original air-cooled motor. The plan is that only a few dozen would be built with that design, and the new design could be implemented quickly. I suspect that part of the reason Tesla is going with a slow ramp-up of production is because they don't want to retrofit a lot of cars later...

There's still going to be a long wait... I think the plan is to use ocean freight, so you have to add like 5 weeks for shipping time. Car #2 might not get here until June...

Tesla needs to ramp up to 40 cars per week no later than August if they want to fulfill all 600 orders this year. That's no small task for a young, immature supply chain...

-Ryan

 

[malcolm]

It begs the question as to whether a multi-speed performance gearbox is achieveable at this early stage in the evolution of electric vehicles. There just aren't enough of these cars in existence right now to justify some large company sitting down and inventing a box which will marry racing car strength to weight ratios with traditional ICE durability.

Maybe it will never need to be solved if PEMs and ESSs evolve to the point where they render any EV gearbox innovation irrelevant.

Is the EV gearbox as much of an interim measure as the REEV?

 

[Kardax]

It begs the question as to whether a multi-speed performance gearbox is achieveable at this early stage in the evolution of electric vehicles. There just aren't enough of these cars in existence right now to justify some large company sitting down and inventing a box which will marry racing car strength to weight ratios with traditional ICE durability.

Maybe it will never need to be solved if PEMs and ESSs evolve to the point where they render any EV gearbox innovation irrelevant.

Is the EV gearbox as much of an interim measure as the REEV?

It comes down to racing. Certain types of races favor quick acceleration, others high top speed, some need both, and with today's technology, you need at least 2 gears to get that, even with EVs.

I don't know what the torque/HP of the new motor is, but if they're still getting 0-60 in 4 seconds, they could get the 0-60 time down lower (3.5 maybe?) and the top speed to 160+ if they attached a two-speed transmission to it. This is really a no-brainer design move; it won't happen this year, but if Tesla survives, it's a near-certainty that a future model Tesla Roadster will have it.

-Ryan

 

[TEG]

The car was supposed to be delivered last year, and now they are still changing the design of the drivetrain. IMHO, at this point, the one gear/two gear question should have been long settled.

Yeah, I wouldn't exactly call it "business as usual" at Tesla with
3 different CEOs in the last 6 months. I suspect that the drive-train switcheroo was a controversial, difficult decision this late in the game. From a probable reduction in top speed, to the image issue with switching to PRNDL to the difficulties in retesting the new parts it had to be a tough call. I am glad they did it though. I think everyone will end up with a better car than was originally planned. Aside from avoiding transmission problems, the new drive-train apparently is better able to deal with sustained high temps, so the PEM is less likely to start restricting power if you were really "tearing it up" on a hot day.