This is interesting tilting delta ?

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I hardly think you are comparing like for like ?

So compare your Morgan to this ? Vigilante

In 1993 the first Vigillante prototype appeared and has to currently be the most powerful road 3-wheeler in the world. Powered by a 700 hp Chevy engine this two seater is an enhanced version of the TriVette. Sprinting from 0 - 60mph in just 3 seconds and with a top speed of over 200 mph the Vigillante is quicker on acceleration and braking than a £634,500 (over $1 million) McLaren F1 road car, and comparable in cornering. The car has a maximum theoretical tip-over limit is calculated to be 3.27 lateral "g" and so the car will slide long before it reaches its tip-over limit. The vehicle is made from a light weight aluminium, honeycomb, foam, and composite tub, whilst the body work is a composite of aircraft fibreglass, Kevlar and carbon fibre in an epoxy matrix helping to keep the weight of the Vigillante down to 1,480 pounds.



Now we are talking !
Now this is interesting. the fact that this "delta" has such a wide rear end and low COG that it breaks away and slides before it can roll over. Is this a lesson for us all to learn?
If width is the restriction for us (barriers etc.) then the COG needs to be low? Or, like the Original posting above...the trike needs a degree of tilting.
I like your cargo i-Lean Paul, that may indeed be the middle ground you are looking for.
 
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The car has a maximum theoretical tip-over limit is calculated to be 3.27 lateral "g" and so the car will slide long before it reaches its tip-over limit.
All that says is that it won't corner fast enough to tip, it'll simply plough straight on because there isn't enough front end grip. It's the basic requirement for a useable delta. Cornering moves weight to the outside front and the delta doesn't have anything there, but fortunately for the delta one front tyre = less front end grip. In other words the delta design self-limits it's own weaknesses to a degree (not entirely as the Robin proved) by being unable to turn fast enough to tip in many cases. There's no weight transfer to that single front in a turn to dig it in. Turn a tadpole sufficiently fast to just lift the inside front and you generate a lot of weight transfer to the outside tyre increasing it's grip, plus it's outboard of the centreline increasing the force required to tip it in the first place.

Then there's this:-
Bob Keyes, the inventor, "The fastest braking possible comes from a triangular wheel arrangement as on the Vigillante and military fighter jets. You can lock up the brakes on all three wheels, on wet pavement, in a corner and it won’t go into a spin because more than half of the braking takes place behind the center of gravity.”

I'll put this politely by saying that's hogwash. On some other boards I'd be a lot less circumspect in my choice of words there:-

  1. Only one front wheel = only one front brake and one front contact patch. In any wheel braked vehicle the bulk of the braking is done at the front because of weight transfer.
  2. Fighter jets don't brake much, they use drag (air brakes and chute) reverse thrust or arrestor wires on a carrier. Brakes are for the last bit of the braking and are rarely used to the absolute max.
  3. Yes it won't spin because the braking is behind the centre of gravity and precisely because of that it doesn't get the weight transfer to work for it. On the contrary the weight transfer works against it, but again this is self limiting. This self limiting aspect is not so fortunate this time as only so much weight can transfer before the front wheel locks. This will happen quite soon on this particular vehicle as 80% of the weight is over the rear. The front end has very little static weight and will receive very little transfer weight before locking.
As I said I fully accept a car based trike is not a pedal trike. I suspect that most pedallers will not be trying to find the cornering or braking limits of their machine and that a delta will provide more than enough in both areas to prove satisfactory at much lower levels of speed than a car. My point is simply that basic physics works against the delta design in it's movement dynamics and because of that it simply doesn't "look right" to my eye. It's the old engineering adage of "if it looks right it probably is". There will be many applications where a delta may be best where dynamics take a lower importance to some other aspect such as cargo.
 
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Winnipeg, Manitoba
My point is simply that basic physics works against the delta design in it's movement dynamics and because of that it simply doesn't "look right" to my eye. It's the old engineering adage of "if it looks right it probably is". There will be many applications where a delta may be best where dynamics take a lower importance to some other aspect such as cargo.
I agree with that statement but find myself preferring the delta platform for a couple reasons. Better turning radius than my Warrior, No need to worry about my knuckles scraping the front tire's in a sharp turn is another big plus. And at 67 I no longer feel the need to fly around corner's, I like the ability to sit and watch the scenery roll by which either style work,s well at.
 
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