Narrow vehicle concept

[Gemaeden]

Some while ago I postulated that a narrow vehicle didn't need to lean in order to remain stable while cornering.

Naturally, with the current state of the art , a narrow vehicle does need to lean and consequently people were skeptical.

At the time I was reluctant to share my research, as I was thinking about patents and intellectual property rights.

I'm no longer bothered about that, so here's how it's done.

First, to get you to understand how this is possible, either carry out the following thought experiment or follow the instructions.

Stand up straight, with your legs about 2 feet to a metre apart.

You are stable, because your centre of gravity, which is somewhere around your abdomen, is neither to the left or the right of your supporting legs.

Now slowly reduce the pressure on your right foot, keep doing it and you fall over, without your foot ever leaving the ground

See what happens, you get weight transfer with no leaning.

If you try the same experiment with someone trying to push you over, you'll find that it is much more difficult for them to push you over if you take the pressure off of the leg on the side that they are pushing from.

Now for how to generally apply this to a vehicle.

To do this, all you need to do is to vary the angle of attack of the coil springs that support the vehicle

Start off with the units either side at 30 degrees to the vertical.

As the vehicle enters the corner, simply raise the outer spring toward the vertical, thus increasing the effective spring rate, as necessary to prevent downward roll, while simultaneously moving the other, so pressure is reduced on the inner tyre, thus also preventing any upward roll effect.

By having the units at 30 degrees to the vertical when going straight, they will carry the same total weight, with zero effective deflection (except the tyre) when cornering at 1g, with the outer spring vertical and the inner one exerting nominally zero pressure, if the vehicle is set up properly.

So a vehicle with an 80cm track and a 40 cm c of g will corner at I g without any lean.

I've also designed another system that provides the automatic countersteering necessary for rapid lean response rate in tilting vehicles, meaning that even narrower vehicles can be self stabilising, without the need for manual countersteer.

Also there is a design for self correcting neutral steering (no designed in understeer or oversteer) that can also use vertical aerodynamic control surfaces, for enhanced cornering power, with minimal drag

I offer these as some sort of evidence that I do not like to speak of what I don't know or am about 99% sure of.

If anyone wants to get involved with any of these projects, without having to figure out how they can work in the real world for themselves, please don't hesitate to get in touch.

I'd just like to add that none of these systems absolutely need an external power source to function, although power assistance can be added.

[Equus]

Gemaeden said:

I offer these as some sort of evidence that I do not like to speak of what I don't know or am about 99% sure of.

Clue: Your proposal counters roll. It doesn't counter weight transfer.


Countering roll is easy (you can do it by a number of methods, but perhaps the easiest is simply to use beam axles with roll centres coincident with the height of the CoG). Countering weight transfer without leaning the mass of the vehicle into the bend, as you do on a bike, requires that you re-write the laws of physics.

The problem is simply that unless you counter the weight transfer, any vehicle will fall over when weight transfer reaches the point where 100% of the weight is being carried by the outer wheels, and for a relatively tall (high CoG), narrow vehicle that happens too soon.

[annodomini2]

Just keep the CoG low:
https://en.wikipedia.org/wiki/Commuter_Cars_Tango

[Equus]

annodomini2 said:

Just keep the CoG low:
https://en.wikipedia.org/wiki/Commuter_Cars_Tango

Well, obviously - but there's a limit to how low you can practically achieve, particularly on a light vehicle when you add a driver sitting high enough to be able to see out.

I'm willing to bet that the 11" CoG height quoted on your link for the Tango is without driver. A well-designed Locaterfield can get down to about 18" and a single-seat racing car is typically about 15" (but is too low to be practical for road use).

Equally obviously, a low-slung car with a normal track width, like a Locaterfield, will also transfer less weight hence out-handle and out-grip an equally low-slung (non-titling) car with a narrow track.

Whichever way you slice it, narrow track is bad for weight transfer, and no amount of trick suspension will fix that unless it actually shifts the sprung mass to counterbalance the weight transfer, by leaning it into the bend.

[Gemaeden]

Equus said:

Gemaeden said:

I offer these as some sort of evidence that I do not like to speak of what I don't know or am about 99% sure of.

Clue: Your proposal counters roll. It doesn't counter weight transfer.


Countering roll is easy (you can do it by a number of methods, but perhaps the easiest is simply to use beam axles with roll centres coincident with the height of the CoG). Countering weight transfer without leaning the mass of the vehicle into the bend, as you do on a bike, requires that you re-write the laws of physics.

The problem is simply that unless you counter the weight transfer, any vehicle will fall over when weight transfer reaches the point where 100% of the weight is being carried by the outer wheels, and for a relatively tall (high CoG), narrow vehicle that happens too soon.

It seems the project is not for you, which is fine, I didn't really expect anyone to get involved, but haven't completely discounted it

However, because you haven't thought about it sufficiently, it is possible that others may just take your word that I am wrong and you are right, as you are a vociferous regular poster and I am not.

I would hope that those who might get involved would understand the concept, but may believe they haven't because of what you have written.

It does counter weight transfer, as practical experiments show. You may need to think about it a bit more.

The main issue with weight transfer is the storing of energy in the outer spring, which is what causes cars to overturn in the 'elk test'.

They don't overturn during the first turn, but rather as a consequence of the counter turn necessary to stay on the road where the stored energy lifts creates a greater roll moment.

My system prevents this

As for re writing the laws of physics:

The centre of gravity moves relative to the effective contact pivot, which is exactly what happens on a motorbike. The rules of physics do not need any rewriting.

Even a motorbike will fall over (outwards) if the centre of gravity is not far enough inward compared to the contact patch of the tyre.

The vehicle will also not fall instantly, but will start to fall and steering corrections can be made to counteract this, like on a motorbike..

It is also quite possible to design a mechanical steering system that limits cornering g to prevent any corrective steering being necessary.

[Kevp]

Gemaeden

What is the purpose of the vehicle? For single person or 2 people inline I assume, otherwise a 7 style car is perhaps the narrowest. The Renault Twizy is narrow, but I don't know what use it is to anybody.

Don't worry about the neigh sayers they don't know the world is flat.

[Equus]

Gemaeden said:

... because you haven't thought about it sufficiently...

Gamaeden, I'm getting well used to your bizarre lack of engagement with reality on this forum. You might think that you can re-write the laws of the land (you can't, but I've given up arguing with your nonsense on that point), but you can't re-write the laws of physics - they won't listen.

I have had a practical interest and involvement with suspension design for decades. I fully understand weight transfer (it was me who ultimately explained it and the full influence of roll centres upon it to Alan Staniforth, but sadly he died before that understanding could be set out in a new edition of his book).

Bluntly: you're talking bks and it's you who hasn't thought about and understood it sufficiently.


I suggest that you toddle off and join our other resident perpetual-motion-fantasy-conspiracy-theorist, Feliks, over HERE... you should get on well together, and having spent the last 15 years mainly talking to himself, he'll probably welcome some company.


To everyone else: please don't throw peanuts to the monkey: he needs help, not encouragement.

Edited by Equus on Monday 15th March 22:54

[mikeveal]

Gemaeden said:

However, because you haven't thought about it sufficiently, it is possible that others may just take your word that I am wrong and you are right, as you are a vociferous regular poster and I am not.

Gemaden, you aren't wrong, Equus doesn't mince his words.
However he is completely correct.

Imagine a line projected from the CoG to the ground, representing the force acting on the CoG. At standstill it will be completely vertical. Accelerate and the bottom of the swings backwards, corner and it swings sideways. Like an imaginary pendulum.

As soon as the point where this line intersects the ground falls outside of a polygon cornered by your tyre contact patches the vehicle becomes unstable and will start to fall over.

Your design does not (significantly) alter the position of the CoG, so it does not alter the point at which the vehicle will tip. By reducing roll, you have reduced the amount the Cog will move to the outside of the corner, but this is negligible and won't give you what you're claiming.

I'm afraid all you've done is re-imagine the anti roll bar and you're not the first to the party. Active suspension has been doing what you suggest for some time. It can not however make a high, narrow vehicle stable in corners. For that you'd need to move the CoG, by erm, I dunno, maybe tilting the chassis would work.

[Fastpedeller]

This shows how it's done (with a human-powered vehicle). They previously had a video, which demonstrated the concept much better than the still photos.
Steering (and tilting) intuitively done by a pair of handles c.f handlebar or steering wheel...... eg when negotiating left turn, move L: lever back and R lever forward.
looks great fun, I'd love to try one
http://www.tripendo.de/
ETA, Now found a very poor quality video
https://www.youtube.com/watch?v=NKW9umqbI4k

Edited by Fastpedeller on Wednesday 17th March 18:58

[boxy but good]

Fastpedeller said:

This shows how it's done (with a human-powered vehicle). They previously had a video, which demonstrated the concept much better than the still photos.
Steering (and tilting) intuitively done by a pair of handles c.f handlebar or steering wheel...... eg when negotiating left turn, move L: lever back and R lever forward.
looks great fun, I'd love to try one
http://www.tripendo.de/
ETA, Now found a very poor quality video
https://www.youtube.com/watch?v=NKW9umqbI4k

Edited by Fastpedeller on Wednesday 17th March 18:58

Mercedes' more modern take on it.
https://www.youtube.com/watch?v=ecPB5ore9h4

[Fastpedeller]

boxy but good said:

Fastpedeller said:

This shows how it's done (with a human-powered vehicle). They previously had a video, which demonstrated the concept much better than the still photos.
Steering (and tilting) intuitively done by a pair of handles c.f handlebar or steering wheel...... eg when negotiating left turn, move L: lever back and R lever forward.
looks great fun, I'd love to try one
http://www.tripendo.de/
ETA, Now found a very poor quality video
https://www.youtube.com/watch?v=NKW9umqbI4k

Edited by Fastpedeller on Wednesday 17th March 18:58

Mercedes' more modern take on it.
https://www.youtube.com/watch?v=ecPB5ore9h4

Looks good - A pity the 'expert?' compensation opened with the 'Robin Reliant' comment, which (for me) reduced his credibility

[boxy but good]

Fastpedeller said:

Looks good - A pity the 'expert?' compensation opened with the 'Robin Reliant' comment, which (for me) reduced his credibility

Quite !
I did contemplate posting a 'warning' but thought I'd let it roll !!

[Fastpedeller]

Fastpedeller said:

boxy but good said:

Fastpedeller said:

This shows how it's done (with a human-powered vehicle). They previously had a video, which demonstrated the concept much better than the still photos.
Steering (and tilting) intuitively done by a pair of handles c.f handlebar or steering wheel...... eg when negotiating left turn, move L: lever back and R lever forward.
looks great fun, I'd love to try one
http://www.tripendo.de/
ETA, Now found a very poor quality video
https://www.youtube.com/watch?v=NKW9umqbI4k

Edited by Fastpedeller on Wednesday 17th March 18:58

Mercedes' more modern take on it.
https://www.youtube.com/watch?v=ecPB5ore9h4

Looks good - A pity the 'expert?' compensation opened with the 'Robin Reliant' comment, which (for me) reduced his credibility

Commentating , not compensation............ Damned spellcheck; I keep forgetting to check it hasn't 'corrected' my spelling.

[CanAm]

Fastpedeller said:

Commentating , not compensation............ Damned spellcheck; I keep forgetting to check it hasn't 'corrected' my spelling.

Or as one poster on here called it, "Auto corrupt."