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Aptera
- Thread starter UCIBtheG
- Start date
voyager
Active Member
RobStark
Well-Known Member
voyager
Active Member
The quintessence and potential of tadpole three-wheelers: (rather) narrow track, tilt (fun), efficiency (energy as well space) below.
The Aptera of course is neither.
The Aptera of course is neither.
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The quintessence and potential of tadpole three-wheelers: (rather) narrow track, tilt (fun), efficiency (energy as well space) below.
The Aptera of course is neither.
The Aptera is, in fact, extraordinarily wide, at 88 inches (2235mm). In comparison, a Hummer H3 is 85 inches wide including the side mirrors, and a Model 3 is 82 inches side with mirrors extended (76 inches with mirrors folded). So the Aptera won't fit through some smaller 1-car garage doors, and it will be a very tight fit going through others. I suspect its width might hinder the vehicle's appeal in Europe where narrower city streets are more common.
But the tradeoffs presented above are quite a bit trickier than implied.
(1) I suspect that a staggered seating arrangement would hurt the vehicle's appeal and reduce sales numbers.
(2) If the Aptera is already as aerodynamic as advertised, there's not a whole lot of aerodynamic efficiency that could be squeezed out by making it narrower.
(3) Making the wheel track so narrow that you'd have to compensate for reduced stability by leaning into turns could be an awfully complicated and expensive engineering endeavor that a small outfit like Aptera would be ill-equipped to tackle. And even if they had unlimited resources, it's not even clear if it would be possible to do so in a safe, cost-effective, reliable manner. (Toyota designed tilting into its i-Road concept vehicle, but that little trike was limited to a top speed of 37mph and never made it into production.)
I personally long for the day that something akin to the Lit Motors C1 (an enclosed, single-passenger, gyroscopically-stabilized electric motorcycle) could be made into reality. But I sadly doubt that day will ever come.
bhtooefr
Active Member
I think you could actually get quite a bit of improved aerodynamic efficiency by going narrower, although it's the main passenger cell's width that matters far more than the overall width.
So a very very VERY rough estimate of frontal area is that it's ~58% of the width times height. (I'm operating off of a photo that's at a too high angle, so the rear wheel isn't visible, but then there's much more of the front suspension visible than there would be to the airstream, and due to parallax, the front wheel pods are also smaller than the photo would indicate.) At 88" wide, 57" tall, that means something on the order of 1.88 m^2 frontal area. (That's also very close to the (wider, lower) Aptera 2e's reported frontal area of 1.85 m^2, so it's plausible.) With a claimed Cd of 0.13, that would mean a CdA of 0.24 m^2.
The VW XL1 had a claimed frontal area of 1.5 m^2 as a result of its lower width (with staggered seating), and a Cd of 0.186, for a CdA of 0.28 m^2. That, however, doesn't have as extreme of a shape.
But then if you go to tandem seating... the 2002 1-Liter-Auto had a 1.0 m^2 frontal area from memory, and a 0.159 Cd, for a CdA of 0.16 m^2 - 2/3 of the aerodynamic drag of the Aptera.
I concur that tilting mechanisms aren't practical - in a high-speed, relatively large vehicle, the forces they have to deal with are extremely high, and you end up using significant energy running hydraulic pumps to tilt the vehicle.
Although the H3 isn't even that big by American standards.
By comparison, the Model X is 89.4" (2271 mm) wide including mirrors, and the most popular vehicle in the US market, the Ford F-150, is 95.7" (2431 mm) wide including standard mirrors and 105.9" (2690 mm) wide including trailer tow mirrors. So, Aptera's overall width is compatible with American roads.
That said, for the European market, even more important than the width hindering appeal (which I agree, it will), there's legal considerations that will require narrowing the track if they want to sell the Paradigm there. The maximum width for a L5e class vehicle (where >50 km/h tricycles fit into) is 2 meters (78.7"), and Aptera's currently 12% over that. (They also need to get the length down, as maximum length is 4 meters (157.5"). I think that'll be easier, though - they'll have to compromise on aerodynamics to do it, but I think the length is available.)
I suspect they've got stability to spare, though, and could actually get away with just... narrowing the track without any further mitigations other than suspension tuning (a stiff anti-roll bar on the front, which would reduce suspension independence, would help significantly with stability, and I suspect with European roads the ride quality would still be acceptable). For a couple examples of current production side-by-side, freeway-speed-capable three-wheelers, the Morgan Three-Wheeler is 1720 mm (67.7") wide, and the Polaris Slingshot is 77.6" (1971 mm) wide (with significantly wider front tires than Aptera), and both are intended for higher-performance (and therefore more likely to produce chassis upset and a rollover) driving than Aptera. Both are RWD, the least stable configuration for a tadpole, although Aptera's dual-motor FWD or tri-motor AWD is also not a stable configuration without stability control intervention. (The most stable configuration for a tadpole is single-motor FWD with an open or torque-sensing differential, as it *cannot* power a tadpole through a rollover - the moment a front wheel lifts, all drive is lost. In dual-motor FWD and any configuration with a driven rear wheel, this isn't necessarily true, as wheels still on the ground can still receive power.)
If they did still have issues, they could lower the passenger cell to bring the center of gravity down (the Aptera 2e was significantly lower, I suspect the Paradigm is higher partially due to market preferences), but the battery may be low enough - both the Three-Wheeler and Slingshot are ICE and naturally have a higher CoG as a result. Additionally, moving the front wheels rearward is a strategy that human-powered tadpoles use heavily to gain cornering stability, at the expense of stability in braking (...yes, I have shoved a human-powered tadpole's chainring into the ground under braking).
They may also want to narrow the passenger cell to maintain suspension geometry and turning radius (narrow the track without narrowing the body shell, and the wheels hit the shell at shallower steering angles), but I think they have room to do that - IIRC they mentioned that the Sol prototype actually moves the passengers closer towards the center in the Transport Evolved video, and that would give additional room for a European-specific bodyshell to be narrower, making room for suspension and improving aerodynamics.
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RobStark
Well-Known Member
Jay Leno did a video on the Aptera recently, and one thing surprised me, at timestamp 2:03:
...
Is that a Tesla charging port on the Aptera?!?!?
The Tesla-style port has been noted in past videos too. I think it would be a good thing if Aptera could make a deal with Tesla to support Tesla Supercharging. And when Tesla eventually releases their CCS adapter, Aptera could leverage off that as well. It is a development car though - so I wouldn't count on it to be in their final product.
RobDickinson
Active Member
They are using 2170 cells so I don't think they got those from a 100D. The body isn't carbon so there's that. And they're using someon elses motors .Actually because of their efficiency and improved aero they will use fewer cells then Tesla.
RobDickinson
Active Member
RobStark
Well-Known Member
So what?
They are a startup autocycle company.
The motors aren't the differentiator. It is the composite body.
They will be lucky to make a 1000 units the first 12 months of production and 50k units the 5th year of production.
In those circumstances it is stupid to make your own motors.
They have to spend time and money configuring their own pack and software to their vehicle.
These are the insightful points about what a startup company specializing in a small vehicle SHOULD do. Elio shot themselves in the head from not following this kind of advice. They were going for this small three-wheeled vehicle idea. They needed a gas engine. There were tons of available options to get a small engine. Just sign a deal to get some crate motors from some motorcycle company and build the car around that!
Instead, they wasted tons of time and money reinventing the wheel, trying to design their own custom gas engine from scratch and drove themselves into the ground and died.
The motor is not the thing. Customizing your small body form factor is your reason for being.
RobStark
Well-Known Member
Apparently, Aptera is also making their own flexible solar cell.
Elio just put out a press release saying they are making an electric Elio.
Elio Motors pivots to 150-mile Elio-E EV, gasoline version still not canceled
The no-frills, high-mpg, three-wheeled car that's been anticipated for a decade still hasn't arrived, but now the company's decided an electric version comes first.
Apparently, Aptera is also making their own flexible solar cell.
Elio just put out a press release saying they are making an electric Elio.
Elio Motors pivots to 150-mile Elio-E EV, gasoline version still not canceled
The no-frills, high-mpg, three-wheeled car that's been anticipated for a decade still hasn't arrived, but now the company's decided an electric version comes first.www.greencarreports.com
Considering how many times Elio has changed their design, I would count them out. They don't have the discipline (and probably lack of talent) to actually get the engineering work done. I had a co-worker put down a deposit for an Elio about 4 years ago when it seemed "imminent", and they still don't have a product.
I think the same thing about Aptera. I said something negative about them in a comment on an article, and a guy asked why I would be negative about them since their delivery was estimated to be the end of 2021. I showed him an article where they were announcing their estimated delivery date was supposed to be end of 2009. I said people have given up believing them.
RobStark
Well-Known Member
The difference is Chris Anthony and Steve Fambro lost control of the company to big investors. Those investors led Aptera into bankruptcy in Dec 2011. Aptera was not a going concern for ~7 years.
Chris Anthony and Steve Fambro purchased Aptera's IP and patents from a Chinese company that had purchased them out of bankruptcy court. And then Chris and Steve re-founded Aptera.
Paul Elio founded Elio Motors in 2009 and has been drawing a salary ever sense.
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