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Posted: 30 Jan 2006, 17:20
by Guest
What exactly is the difference between V-keel and single, from a suspension point of view? Both moves the lower pickup to below the "tubline" (front one specifically), which gives you more favorable camber in roll and probably gives you more "anti" to work with. Unlike Zero-keel or Twin keel, where there might be some aero benefit to be exploit, neither single or V left the bottom of the nose particularly clean for aero, with V might even be more disruptive to my untrained eye. One thing I could see is that V might be lighter as it does not need that long rib running along the bottom of the nose., but other than that I really don't see that much of a difference from purely suspension point of view...If anything V is a derivation of single keel.

Posted: 30 Jan 2006, 17:51
by Spencifer_Murphy
If anything V is a derivation of single keel
Thats exactly what it is...basically its a singe keel which has been hollowed out for better aero. I spose the only difference from a suspension piont of view would be that being hollow it maybe a little less stiff if designed poorly...which could have the same sort of negative effect as a flexing chassis.

Posted: 01 Feb 2006, 14:27
by Rafael de Oliveira
Somebody have a drawing or a picture showing the major diferences between the diferents kinds of keels ?

Posted: 01 Feb 2006, 14:45
by jezzwa

Posted: 01 Feb 2006, 15:26
by kilcoo316
Spencifer_Murphy wrote:
If anything V is a derivation of single keel
Thats exactly what it is...basically its a singe keel which has been hollowed out for better aero. I spose the only difference from a suspension piont of view would be that being hollow it maybe a little less stiff if designed poorly...which could have the same sort of negative effect as a flexing chassis.

I tend to think the reverse. The _V_ is making a triangle out of the suspension pick-up to the monocoque, so should be stiffer (for the same weight) as a conventional _|_ cantilever type mounting.

Posted: 02 Feb 2006, 02:17
by Spencifer_Murphy
True, I didnt think of that...ure probably right...it maybe stiffer too. But if its badly designed it could be less stiff?

Posted: 02 Feb 2006, 03:24
by Guest
Triangles are inherently rigid because the shape cannot be distorted if the links are solid. As apposed to a box section which can easily deform even if the links are strong. The V-keel should be the most ideal suspension design in terms of geometry and rigidity. I don't think it's the best for aero, but it is a reasonable compromise.

Posted: 02 Feb 2006, 04:39
by Guest
i don't think the single-keel as they were were any less stiff, just the v-keel an be made lighter....

Posted: 04 Feb 2006, 21:54
by Guest
Midland turned out to be a bit of a surprise in the fact that they went with a no keel/twin keel design although I haven't seen any solid pictures as to what the suspensin setup is yet. Either way I am happy to see that Midland is taking some chances with their car design.

Image
Image

Posted: 05 Feb 2006, 01:27
by se7725
post above was me, sry

Also i found this pic of the lower member of the suspension
Image
From what i can see it is some sort of twin keel set up.

Posted: 05 Feb 2006, 01:34
by se7725
Image
a little bit bigger picture showing a bit more detail.

Posted: 05 Feb 2006, 04:44
by manchild
Lower wishbones front is connested on some sort of curved twin keel while the rear end of the wishbone seams to be connected like no keel.

The keel looks something like this / \

Posted: 05 Feb 2006, 05:28
by se7725
I think we should name it :D What do you think about an A keel?

Posted: 11 Feb 2006, 04:08
by se7725
Image

Well it looks like STR is using a single keel, no real surprise.
I really thought before all the car lauches that there was a good chance STR was going to go radical because they have nothing to loose and they could develop some new concepts for RBR. Meanwhile it looks like Midland has really lauched a car that has some interesting features.

Posted: 11 Feb 2006, 04:29
by DaveKillens
For a high performance racing car, it is critical to keep the chassis and locations of the suspension pickups as stiff as possible. Any deformation or flex would allow unwanted suspension movement. This is a fundamental rule that all adhere to.
A triangle is the stiffest and strongest geometrical form. Just look at any steel structure, be it a bridge, or interior supports for a large roof. It's made up of a lot of triangles.
http://www.cwc.ca/products/trusses/shapes.php
A single keel design is basically a strut that projects downward from the chassis. Think of a fishing pole, it too is a strut, but as we all know, it flexes a lot. So alhough a single strut (or beam) is simple, it has to be designed very stiffly to minimize any flex.
So if you have to hang the suspension pickup points away from the chassis, a triangular structure is superior from a mechanical viewpoint. But of course, it is two struts that meet, versus a single strut for a single keel design. Of course, mechanically, the best way to go is to attach the suspension pickup points directly to the chassis, which is what a no keel is all about. It's mechanically and aerodynamically superior, but at present, it forces radical and innovative suspension geometry that at present is giving engineers headaches.