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Mules, EP's and VP's

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So I am wondering from you old hand Roadster types if you can fill in some of the blanks on the process of development.

We know there is already a clay model and a mule or possibly 2 and now two EP's. How many EP's were there for the Roadster ?

When were the crash tests performed? On EP's or VP's or in between.

How many VP's for the Roadster BEFORE the were ready for production? I know they are still making VP's - which are now kind of marketing cars.

What are your ideas of what the time line will be from here forward ?

I am anticipating 2 years to go through the entire process - which I believe it was for the Roadster but I am sure that many of you out there have actual dates from the Roadster progress that we might be able to apply loosely to the Model S project. All that insight would be greatly appreciated :smile:
 
You can read all about Roadster EPs and VPs here:
http://www.teslamotorsclub.com/tesla-roadster/990-engineering-prototypes-eps.html
http://www.teslamotorsclub.com/tesla-roadster/429-validation-prototypes-vps.html

Maybe Doug has learned more being able to interview staff in person, but I would say we may still not know how far along they really are.

If you twist my arm, I would guess that the White and Silver we saw this week were EP1 and EP2, just like when they introduced the Roadster.
So, if they follow the Roadster dev path it would be something like 8 more EPs, some number of which would go to crash testing. Then the VPs would probably start to come as Tesla tries their hand at building it entirely themselves in their own factory. That could be well over a year away. I bet these EPs now are hand built/custom fabricated at great expense.

They seem to build some VPs as "marketing cars", so once we get past the EP stage, there could be an ongoing trickle of VPs going to the stores as demonstrators and loaned to the staff for evaluation of ongoing changes and improvements going into the vehicles.

But I am just guessing here.
 
Wow - if they really built it using SpaceX equipment that would be novel and exciting. Too bad we didn't think to have Doug ask them about it.

There are quite a few custom builders that will fabricate "one offs" for you though.
 
Rachel told me the white one is only a roller. Any picture inside will show it has a cardboard "floor" at about halfway up the seat height.

As for how long, remember that the first time it went slow because hey not only had to develop a car from and existing platform but also they had to build a company from scratch.

This time they are building a car from scratch and now they have to build a factory from scratch.
 
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If you twist my arm, I would guess that the White and Silver we saw this week were EP1 and EP2, just like when they introduced the Roadster.
So, if they follow the Roadster dev path it would be something like 8 more EPs, some number of which would go to crash testing.

I doubt that Tesla Motors will spend any more money on Model S until they get the US gov't money officially approved. No more EPs at all until they know the program is moving forward.

Everything to get them thru the unveiling was designed to build a deposit base and demonstrate viability, both for investors and the US gov't loan application. There is no point in doing anything else on development on the Model S until there is approval of the loan money.

Tesla has the ability to take deposits and I suspect when they have 1,000 Model S owners, they will make a press release to that effect. I am willing to wager they are at 100+ already.

We will find out in May when the order number positions are assigned to those that made a Model S deposit.
 
Yeah, probably something like that. I am not going to try to predict the future, but it looks like a whole lot will need to happen between now and Q3 2011...

If they build their own chassis from scratch then the current cars are more "mules". If they use an existing chassis then perhaps they are "EPs" and much less chassis engineering will need to take place.

Well, I think it is time for me to give it a rest. I feel like this sort of speculation will just end up being annoying. We got a healthy dose of "here is where it is", so now it is time to wait some more and see what happens next.
 
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I am going to guess that the dark gray was a buck,
the silver could be a mule (based on Mercedes chassis),
and the white might be EP1 (Tesla's own chassis) that isn't quite finished yet.
Or maybe the white is another mule... Not sure.

Again, just guesses... Based on clues seen in various pictures.
 
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It would be interesting to know if Tesla uses any of the Model S deposit money in it's operations now or for the production of the Roadster. I'd like to think not, but I'd still like to know.

I also suspect Tesla saw a little increase in Roadster orders because of the Model S unveiling. Nothing says viability of a company like new productions (just look at Chrysler)--kidding about that one. :tongue:
 
It would be interesting to know if Tesla uses any of the Model S deposit money in it's operations now or for the production of the Roadster. I'd like to think not, but I'd still like to know.

I also suspect Tesla saw a little increase in Roadster orders because of the Model S unveiling. Nothing says viability of a company like new productions (just look at Chrysler)--kidding about that one. :tongue:

Accoding to the sales agreement for the Model S, they can use the deposit for anything they want. If Tesla goes bankrupt, it is not in escrow. You are just an unsecured creditor.

I hope they get more Roadster orders from the publicity. They need to keep that production at 20 Roadster per week for that product to be sustainable long term. Their showroom webpage is actually starting to look full. They have four different models available.

1) Roadster
2) Roadster Sport
3) Model S
4) Model S Signature

Tesla Motors - Tesla Showroom
 
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I doubt that Tesla Motors will spend any more money on Model S until they get the US gov't money officially approved. No more EPs at all until they know the program is moving forward.

According to Mike at Menlo Park, he thinks they will get a demo (at least to sit in) in a couple weeks or so. Of course he doesn't know. But it sounds like there may be more than EP1 and 2 coming down the pipe.
 
So what is the difference between a Mule, a Buck, and EP, and a VP ?
I'll give a try here.

Buck
It only looks like a car but it really isn't. It's made out of foam, clay, wood or some other "easy to work with" material. It's purpose is to get the outside design right.

Mule
Mule is a donor car used to develop and test different new car subsystems. It can look completely different from the new design or quite similar if you mount you new body panels on the donor. It could be non-drivable.

EP - Engineering prototype
It could be based on a donor car (early EP) or using a newly developed chassis (more developed EP). If it is based on a donor car, many subsystems are from the new car. Usually drivable except when something brakes or is under work.

VP - Validation prototype
The design of new car is (almost) finished. VPs are used for extended testing to find hidden problems, testing of smaller additions, marketing etc.

There are many more discreet step in development of a new car. These basic designations are there to more easily distinguish different levels of prototypes.
 
WarpedOne's description is close to what I would say, but I think of it a bit more like this:


Buck
It only looks like a car but it really isn't. It's made out of foam, clay, wood or some other "easy to work with" material. It's purpose is to get the outside design right and sometimes used in a wind-tunnel to test aerodynamics.

Mule
Mule is a donor car used to develop and test different new car subsystems. It can look completely different from the new design or quite similar if you mount new body panels on the donor. Usually it is drivable to some limited extent. Bodywork could be bondo, fiberglass or some other non-production material.

EP - Engineering prototype
Generally, I think this is meant as a best effort to make a final car that engineers think could be built. After the marketing folk, beta customers, and bean counters get a look at it they generally want changes to be made. Frequently this involves fine tuning materials, making it more comfortable and working on cost reductions. The factory people may suggest changes to make it easier to build in large quantities.

VP - Validation prototype
The design of new car is (almost) finished. VPs are used for extended testing to find hidden problems, testing of smaller additions, marketing etc.

----

I think the old white magnum wagon was a mule of sorts just to test the new drivetrain even though the exterior didn't attempt at all to look like anything new.

I think the dark gray car was probably a "styling buck" meant to finalize the exterior design, but it may not have a provision to ever be driven. (I could be wrong).

Now the latest white and silver cars - it is a bit hard to know if they are "final mules", EPs or what. The question is the chassis underneath, and weather it is production intent. Are one or both of them based on a pre-existing car chassis, or are they new from the ground up Tesla designs? If the former, is that the way they plan to go into production? Lets just say hypotehtically they they were a reskin of a Jaguar XF (picking a random example), with a Tesla body and a Tesla drivetrain. If that were the way they planned to produce them then they are probably EPs. If, on the other hand, they are currently based on a production chassis, but the intent is to make a new Tesla chassis then they would be more like mules.

We know no matter what, Tesla is likely to borrow components from other cars... Like ABS system, brakes, windshield wiper motors, etc, etc... But just how much? Will they get a whole chassis design (basic frame) from someone else or are they going with their own design?

Also, some had said if they based it on a production car they could avoid crash testing, but I think that could be wrong. Roadster was heavily based on Elise but still had to be crash tested. My guess is no matter how they build it enough is different from any production car that they would need to do crash tests.

Anyways, keep in mind that I am just guessing at all this, and I don't work in the industry so my guesses could be rather wrong.
 
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Will they get a whole chassis design (basic frame) from someone else or are they going with their own design?

Also, some had said if they based it on a production car they could avoid crash testing, but I think that could be wrong. Roadster was heavily based on Elise but still had to be crash tested. My guess is no matter how they build it enough is different from any production car that they would need to do crash tests.

http://www.teslamotorsclub.com/tesla-model-s-whitestar/2472-doug-model-s-reveal-12.html#post24040
You did post an article where Mike Donoughe said they are still looking at using a preexisting chassis. That would mean pretty much none of the cars can be considered "full mules"/EPs until they know what chassis they are going to use. Of course they can still get some rough idea of packaging even without a finalized chassis, but they can't move too much beyond that (though it appears none of the cars unveiled that day had even the planned rough packaging). They could be waiting on the loans before further development.

On the crash test part, I suspect you are right that they will have to redo it regardless of chassis choice. The major part that they can't avoid changing is adding a heavy battery pack and I don't see how they can escape crash testing with that big of a change.
(though looking at NHTSA tests it seems they use the same data for the Escape, Escape Hybrid, Mariner, Mariner Hybrid).
 
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Yes, I know I posted that quote, but I also posted a bunch of quotes where they said completely new Tesla chassis. So, honestly, I don't know which it will be.

I suspect the silver car driven this week is based on a Mercedes chassis (based on the way the radiator looks in photos), but I don't know if that represents production intent or not. It could be that they are considering two different production paths depending on how things go.