aerodynamic car idea, a wild thought

[close circuit]

Originally Posted by kach22i

With my own design exercises I find that adding those little details an advantage that helps mature it.

The more details you address such as; engine access, wiper blades, air intakes/exhaust ventilation, interior design, chassis structure, buildability, headlights, turn signals, side view mirrors, door handles, gas cap, gas tank location...................the more detail addressed, the more thought out and realistic it is, and perhaps the more appreciated by the viewer.

Imagine some perspective client or employer looking at your drawing for five minutes without saying a word and then suddenly they say how do you get in the trunk? Without the little seams and joints providing clues the question could come up.

And yes; that rear hatch opening just as the door opening size and shape is going to affect crash safety. You don't have to do crash safety simulations as the general designer or stylist but you don't want to raise any read flags and look impractical.

Now if you were in a design competition sponsored by some Tier-1 supplier that just invented some super material which would allow you to do things never before possible, that is a different opportunity and a different expression of design to solve or exploit and something different would emerge.

you're absolutely right, designing a car can require quite an advanced research and development since the sheer number of production if nothing else. but it still feels like they don't pay enough attention to aerodynamics, they could be more efficient and better looking at the same time with no more effort than now made by the companies. by the way I'd think this concept as a rwd electric and batteries in the floor tesla style. trunk -frunk- space would be the most important impracticality I guess. and there's the thing with three wheel handling which I don't even know what to think about.

[freebeard]

Just curious, do you have much exposure to the rich history and the theory of reverse tricycles. Because there is a lot.

In the midst of Kach22i's laundry list he slipped in buildability. This is different to everything else on the list, and will determine the design as much as the aerodynamics. Are you thinking of something spun out of pure unobtainium, an aluminum monocoque with fiberglass fenders, or a donor Geo Metro and coroplast?

Here are some example that have been posted in http://ecomodder.com/forum/showthrea...11732-234.html in the last 24 hours:




Here is my own effort. They could be converted to 3 wheelers; but I'd recommend front wheel drive with a reverse trike.



And the pure Template body of revolution (blimp shape), except with the equator lowered, in motor home size:

[close circuit]

Originally Posted by freebeard

Just curious, do you have much exposure to the rich history and the theory of reverse tricycles. Because there is a lot.

In the midst of Kach22i's laundry list he slipped in buildability. This is different to everything else on the list, and will determine the design as much as the aerodynamics. Are you thinking of something spun out of pure unobtainium, an aluminum monocoque with fiberglass fenders, or a donor Geo Metro and coroplast?

Here are some example that have been posted in in the last 24 hours:

Here is my own effort. They could be converted to 3 wheelers; but I'd recommend front wheel drive with a reverse trike.

yes I'm familiar with these and what I wanted to do is imagine a cabin design so it'll accommodate five people with ease. I know fwd is the answer for both traction and regen but I thought a bigger frunk could be possible if I didn't disturb the front axle, also I really like rwd. that inflatable system on the go was one of the things that crossed my mind for the sake of a street legal rear end, you've visualised it nicely. the car in the first picture is roughly the external design I would adopt though with one too many wheels.

[freebeard]

So what happens next? One approach is to finalized the envelope and then fit the components inside; another would be to arrange the components and then 'flow' the envelope around it. The former limits your choice of components, the latter requires you declare your variables.

The Template side view that kach22i has a front view as well. It's half-circular and flat on the bottom. The curved underbody you've shown is more similar to a Luigi Colani design based on the shape of a water strider.



It is flat on top and curved on the bottom to counteract the lift that the Template would produce. Another reason I prefer the Trophenwagen-type tail end.

When you get to the door cut-lines, my favorite four-door is a Ford concept, the Evos:


Mainly because the front butterfly doors hinge on arms to the windshield center.

[kach22i]

Originally Posted by freebeard

The Template side view that kach22i has a front view as well. It's half-circular and flat on the bottom. The curved underbody you've shown is more similar to a Luigi Colani design based on the shape of a water strider.

Side bar discussion on Luigi Colani design:
When I have gone rear wheel drive in my design studies, be it 3 or 4 wheels, I find the area taken up by the engine/transmission and or rear differential/axle combined with the suspension components leaves only narrow slots for possible sweeping up of air - like narrow tunnels. I do a lot of sections and cross sections by hand on graph paper to scale (old school).

These air slot tunnels are the resultant without going into elaborate and exotic designs using the front fork suspension of a motorcycle at the rear wheel (yes on light weight 4-wheel designs) or electric hub drive systems, or teardrop shaped struts as on race cars.

Drive shafts connected to electric motors are more versatile, but could be limited in HP by the angle of the U-Joints and other design demands. These unknowns for the non-engineer and someone interested in aerodynamics is why many default to established platforms and concentrate on the vehicle's skin. This unfortunately leaves good food on the table uneaten.

Going back to the original design posted: which could in fact have narrowly spaced twin rear wheels or one single rear wheel, it is my understanding that all three tire contact points should have equal weight on them.

I believe this is one reason why Freebeard said he favors front wheel drive on a reverse trike, the weight balance.

If you add two 150 lb passengers to the rear seats that is 300 lbs more on the rear axle. Assuming the front passengers and driver are midway of the wheelbase as they usually are, you may only have issues when fully loaded. However they could be serious issues, well anything in a moving vehicle can become serious, this is serious stuff.

There are a few good websites discussing the handling of reverse trikes, I have them bookmarked somewhere - just Google them yourself.

In general best to go longer with your wheelbase than too short when in doubt. From what I can see casually looking, you are within the safety zone of operation with your design - roughly speaking if all else is balanced right.

[kach22i]

Originally Posted by freebeard

I love your work Freebeard, did I ever post for you the work of the Industrial Designer over in SE Asia which built a hovercraft based on similar geometry?

PM me your e-mail and I will see what I can dig up for you.

That designer's name is Ganis Pribadi, I'm friends with him on Facebook but often cannot read what is written because it is in a different language.

Several photo albums of interest, let me know if you cannot see any of them.

https://www.facebook.com/ganis.priba...5%3A1490107198

He used to be all about his designs, then he started making babies.

[freebeard]

Thanks.

I can not see any of them because I avoid Facespook (and WalMart) on principal. If you find an example you could attach it to the PM. TIA

I haven't done any new modelling in a year. I will accept that as encouragement to do more. Here's a [partial] hovercraft; a stern-wheeler.

[cRiPpLe_rOoStEr]

Considering those Japanese microcars that are not so great when it comes to the aerodynamics, but still reach some good fuel-efficiency with 660cc engines, eventually the engine out of a big scooter such as the Suzuki Burgman 650 would be reasonable. The only problem would be finding a way to reverse-gear it.

[kach22i]

Originally Posted by cRiPpLe_rOoStEr

Considering those Japanese microcars that are not so great when it comes to the aerodynamics...........

I went to a Ford employee presentation on the future of autonomous vehicles a while back, and they had a video showing how traffic may look/act and how this may influence architecture and pedestrian interaction as well as automobile design and terms of automobile use/ownership.

The thing which was intended to blow your mind was at the featured intersection how cars kept going but narrowly missed each other without slowing down.

Part of the reason they could do this was the single pod teardrop cars which looked like bananas on end or vertical teardrops similar to the design below (shorter targets).

https://www.pinterest.com/pin/195132596324848111/

Designed by Woo-Ram Lee, Moville is a compact single passenger vehicle that comes in a tear drop shaped. The concept car features artificial intelligence and zero-emission drive train. It uses electromagnets to rotate the ball wheels.

I think these smaller pod cars were supposed to be intercity driver-less taxis that never went on the highway. However they were possibly very aerodynamic, it was hard to tell in such a short video as they whizzed by.

I'm just saying that if you take out the steering wheel or even a joystick, you can pin the occupant in there like a coffin thereby reducing internal volume requirements and any issues with observability and blind spots as the vehicle drives it's self.

[freebeard]

Circle-8 races ...all day every day!

In the last century I designed a velomobile that was pedal powered, with big front wheels (like a wheelchair or Frank Lloyd Wright car) and a variable wheelbase. What I'm seeing here is no opportunity for exercise.

Maybe an autonomous e-bike?
________

Pinterest I'll tolerate, although they used to show more than three items. In this case, that did give up this:


http://blog.picodulce.com.ar/wp-cont...del-futuro.jpg

Sort of a New Porsche 64.