Semantics?

[kerbe]

I'm not certain about the appropriate terminology, but stick with me...

I've been thinking about the "3-wheel/4-wheel" definition that kept Aptera from being eligible for funding. Is there, in the official definition of "automobile," any mention of the specific placement of those wheels?

I've seen a number of vehicle designs that have use two wheels in tandem -- either independently-suspended or attached as one (as on the rear axle of a truck).

I wonder if A) adding a second rear wheel to the Aptera would allow it to be classified as an "automobile" even though it was still in a "tripod" format; B) widening the rear "nacelle" to accomodate a second wheel would have a significant impact on the aerodynamics of the vehicle (as we know it did when two rear wheels were mounted at the rear corners); and C) if two independently-suspended tandem rear wheels would make for a more comfortable driving experience.

I'm an artist, not an engineer -- I'm trying to describe something visual using the non-visual medium of written words. Please forgive me if I've made any nomenclature errors: I'll gladly accept critique or correction -- but don't bother chastising me for my lack of expertise.

[APTERA 2356]

The problem as I see it is that the Aptera gains several perks because it is defined as a motorcycle. for example Carpool lane usage, no requirement for crash testing, lower insurance rates? no need for bumpers ETC...

While Aptera has built this vehicle with the safety of a car, because it has three wheels they didn't have to. add a fourth wheel, it is a game changer and would probably cause A higher price to cover the extras.

[kerbe]

But they also lost out on MILLIONS of dollars of funding that went to other people's IDEAS for 4-wheeled vehicles.

[APTERA 2356]

I thought the rebates went to the buyers not Aptera, That being said Aptera would have incurred a lot of additional design and testing costs. the mileage would have suffered and there would have been additional delays in delivery waiting for crash testing.

I'm not sure if Aptera would benefit directly enough to make up for the negatives.

[pudgie_child]

I thought the rebates went to the buyers not Aptera, That being said Aptera would have incurred a lot of additional design and testing costs. the mileage would have suffered and there would have been additional delays in delivery waiting for crash testing.

I'm not sure if Aptera would benefit directly enough to make up for the negatives.

kerbe is talking about the low-interest federal loans that went to prospective makers of 4-wheeled electric cars (Nissan, Ford and Tesla):

http://www.latimes.com/business/la-fi-autos24-2009jun24,0,266618.story

Aptera would have incurred a lot of additional design and testing costs. the mileage would have suffered and there would have been additional delays in delivery waiting for crash testing.

I'm not sure if Aptera would benefit directly enough to make up for the negatives.

Color me skeptical about the advantages of their 3-wheel design. While there will be benefits of the Aptera 2e design, there are going to be some definite costs:

- the wide distance between the front two wheels
- the wheel housings are going to be prone to scratches and other damage from normal driving and curb-side parking.
- with only three wheels, the Aptera 2e will not qualify for the $7,500 PHEV tax credit

My hunch is that the 3-wheel design (with its unique steering and balance issues) has likely caused more delays than a traditional 4-wheel design would have.

[KarenRei]

the wide distance between the front two wheels

As far as I can tell, that has little to do with the use of a three wheeler design. It has to do with a shrouded-front-wheels design.

- the wheel housings are going to be prone to scratches and other damage from normal driving and curb-side parking.

Same as above.

- with only three wheels, the Aptera 2e will not qualify for the $7,500 PHEV tax credit

That's neither their fault nor something that was in place when they started.

The advantages are lower parts count, lower maintenance, lower mass, and a closer approximation to an ideal teardrop shape, with the corresponding reductions in required battery mass (and thus cost) and charging time. Not exactly trivial.

[Holz]

I think we have already had some of this discussion on tandem rear wheels. See http://www.apteraforum.com/showthread.php?p=30597&highlight=tires#post30597

It makes sense to me, but again, as one track that Aptera would pursue (in addition to the 3-wheeled models), as a mechanism to tap into the American Recovery and Reinvestment Act funding. Yes, they would have to have a plan on the books that included a bumper along with the 4 wheels etc. But the cash infusion might make it worth doing the testing on this while also permitting work to move forward on technology that was common to both the 3- and 4-wheeled versions. The 4-wheeled version would just turn out to be "unsuccessful" in the end, just like a lot of prototypes are....or maybe they would find out some things that would be positive and useful with 4 wheels, bumpers, etc.

I'm not certain about the appropriate terminology, but stick with me...

I've been thinking about the "3-wheel/4-wheel" definition that kept Aptera from being eligible for funding. Is there, in the official definition of "automobile," any mention of the specific placement of those wheels?

I've seen a number of vehicle designs that have use two wheels in tandem -- either independently-suspended or attached as one (as on the rear axle of a truck).

I wonder if A) adding a second rear wheel to the Aptera would allow it to be classified as an "automobile" even though it was still in a "tripod" format; B) widening the rear "nacelle" to accomodate a second wheel would have a significant impact on the aerodynamics of the vehicle (as we know it did when two rear wheels were mounted at the rear corners); and C) if two independently-suspended tandem rear wheels would make for a more comfortable driving experience.

I'm an artist, not an engineer -- I'm trying to describe something visual using the non-visual medium of written words. Please forgive me if I've made any nomenclature errors: I'll gladly accept critique or correction -- but don't bother chastising me for my lack of expertise.

[Ardie3301]

Kerbe,

Your discussion about the 3 wheel / 4 wheel issues have merit, but I think we need to remember that these issues will shake themselves out sometime in the future.

Currently Aptera is engineering/designing a 3-wheel vehicle, the 2e. And later, probably the 2h hybrid, 2g gas-only, and 2d diesel variants.

As a 3-wheeler, Aptera was not -required- to do a battery of expensive crash tests. But as a rebuttal, Aptera *did* perform an extensive series of simulations, and they *did* perform some body crush tests, which showed that the 2e's body exceeds (by over 4 times) the minimum requirements.

As a 3-wheeler, the 2e will enjoy life in the HOV lane, because it is classified as a "motorcycle," and not a "car." As such, you can ride in the HOV lane alone.

As the 2e's design classifies it as an "enclosed motorcycle," drivers do *not* need motorcycle licenes. An ordinary operator's permit will do.

Since the 2e is a motorcycle, Aptera is *not* eligible to feet at the public money trough to obtain zillions in government subsidies for development and production of an environmentally friendly and low gasoline use car.

Since the 2e is a motorcycle, we, as potential buyers, will *not* be able to belly up to that same money trough to claim a $7,500 buyer's credit in purchasing such a nice car.

And finally, since it is a motorcycle, we, as potential buyers, will *not* be able to belly up again and claim a $4,500 buyers "cash for clunkers" allowance even if we bring in a qualifying clunker for trade-in. (Ah, well. By the time the 2e is in production, all that money will be -long- gone.)

- - -

HOWEVER, Aptera's grandiose plans are to develop (after the 2e/2h/2g/2d are in production) a 4-wheel vehicle (a "real car," currently known by the code name Palomar) that *will* allow Aptera to apply for any money remaining in the sofa cushions of the Federal Treasury to develop and produce a car.

It will be crushingly (yuk, yuk) costly to run all the crash tests required and to add all the safety equipment manded by federal law to market a car in the USA, but that's the way it goes. Hopefully, Aptera will have a reliable revenue stream from us, the 2x buyers, to finance it.

As a car, you will *not* be able to use the High Occupancy Vehicle lane alone. You will need additional persons aboard. 1 or 2, depending on the HOV in question. Most all of them need only 2 persons per vehicle, but the I-10 in Los Angeles requires 3. Pets? Do not count. Dead bodies? Sorry, they don't count either. Pregnant women? Don't go there. Nationally, there have been rulings each way. I suspect as the years march onward, 3 persons per vehicle may become the norm, but "motorcycles" will probably escape such a change in requirements.

As a 4-wheel car, Aptera will probably be able to more directly compete with more mainstream electric cars, such as the Chevy Volt and the Fisker Karma.

- - -

What will the Aptera Palomar (4e?) wheel configuraton be? That's anybody's guess right now. But in answer to your question (A), four wheels is four wheels. Its that simple. I don't care if you try to jack one up off the pavement like some cement mixers do to their rearmost set, they are tires that -can- rest upon the pavement, and therefore, are counted.

For question (B), widening the tailfin where the rear wheel resides will definitely have an impact on the aerodynamic drag, but how much? That's a question no one can answer until the shape is finalized. But it is kinda a given that the total drag from tire rolling resistance will increase by 33%.

Finally (C). A tripod design with two rear wheels -very- close together (à la the BMW Isetta) may work out, or possibly a tendem tailwheel design. Depends on when happens when you want to drive in tight circles, and what the CG will be with 2 big people in the front seats and nobody in the rear seats as you squeal through that right turn.

-- Ardie

[NmGfan]

And Ardie, for that Palomar launch, let's not forget the hundreds of millions of dollars that will be needed to launch a new-from-the-ground-up EV like Tesla's Model S.

:happy0025

[esmith]

But it is kinda a given that the total drag from tire rolling resistance will increase by 33%.

I really don't think it will. Tire rolling resistance depends on CRR, which is a function of the material of the tires, and on weight. The number of tires is not important, at least to the first order of approximation.

The four-passenger version will have to be 4-wheel, or else it'll be prone to tip over during turns with heavy passengers in rear seats.

[KarenRei]

I really don't think it will. Tire rolling resistance depends on CRR, which is a function of the material of the tires, and on weight.

I believe the concern was over the anticipated increase in weight.