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Bio Mechanical Suspension systems
Posted: 04 Dec 2008, 06:04
by fastback33
Okay this is kind of a repeat from my active suspension idea thread from last year. However, If you had a Suspension system (Think unconventional) that acted more as a humans muscular structure rather than the A arms we see today, would in a sense, you be able to push the tire down further thus generating more grip and needing less aerodynamic pressure? basically (I need to take a biology class), You could have a pneumatic system siffening and softening as well as pressurizing the tire with out the need of outside forces Or Springs(I.E. air pressure).
For simplicities sake, the picture i have in my head is say an actual arm attached to a wheel from the shoulder down, pushing the wheel down. (That is the basic idea atleast)
What do the Guru's think? I'd like to hear your opinions!
Re: Bio Mechanical Suspension systems
Posted: 04 Dec 2008, 10:08
by tomislavp4
Well I´m not exactly a guru but...
I think it would work in corneringif you can design/build it. When you corner you experience roll because the more of the weight is on the outside whell, so if you could stiffen the shockabsorber (your muscle) on that wheel you´ll experience no roll

No roll=no camber change
Just my 2 cents....
(edit) Oh yes ant you´ll still need aero if you want more pressure from your arm. Let´s say your car weigh 500kg, if the muscle acts strong enough it will lift the entire car from the ground thus loosing grip, right? So with aero you have say 1500kg, the muscle can push the wheel down with greater force

Re: Bio Mechanical Suspension systems
Posted: 04 Dec 2008, 14:46
by machin
The rules of physics I'm afraid scupper this... any force needs an equal an opposite force to balance it... that's just the way it is... so you can't push down constantly with anything unless you have something to push against.... e.g. can you push down with your feet whilst standing still? You can momentarily push down harder (i.e. at the start of a jump) but this is followed soon after by you leaving the ground.. this isn't a good situation for a car!
Same applies during corning..... so you can't get something for nothing.....
Re: Bio Mechanical Suspension systems
Posted: 04 Dec 2008, 14:49
by machin
tomislavp4 wrote: So with aero you have say 1500kg, the muscle can push the wheel down with greater force

The aero forces, assuming the wing is fixed to the car, will be transferred to wheels whether they're connected via "muscles" or big chunky pieces of metal (or nice slender Carbon fibre structures).. if the muscle/metal/carbon fibre isn't strong enough it breaks and the wing will no longer push down on the wheels....
Re: Bio Mechanical Suspension systems
Posted: 04 Dec 2008, 14:55
by xpensive
Oh'boy machin, I wish that I had a fraction of your politness..*L*
Re: Bio Mechanical Suspension systems
Posted: 04 Dec 2008, 20:48
by tomislavp4
machin wrote:tomislavp4 wrote: So with aero you have say 1500kg, the muscle can push the wheel down with greater force

The aero forces, assuming the wing is fixed to the car, will be transferred to wheels whether they're connected via "muscles" or big chunky pieces of metal (or nice slender Carbon fibre structures).. if the muscle/metal/carbon fibre isn't strong enough it breaks and the wing will no longer push down on the wheels....
And your point is?
Everyone allready knows what you wrote, it´s common sense. If someone had the knowledge and technology to build this "bio suspension" don´t you think that calculating the stifness of that stuff would be a piece of cake for him?
Re: Bio Mechanical Suspension systems
Posted: 04 Dec 2008, 21:42
by Ciro Pabón
Fastback, I think you already got the idea that pushing down will make the car to jump.
However, have you ever seen a car that, by itself, jumps over an obstacle? I have...
Check what the car does at 1:43 into the video: look, mom, no ramps!
[youtube]
http://www.youtube.com/watch?v=eSi6J-QK1lw[/youtube]
J'espère que, comme nous, vous avez apprécié le spectacle! (I hope that, like us, you have appreciated the show).
Bose suspension.
Re: Bio Mechanical Suspension systems
Posted: 04 Dec 2008, 22:08
by machin
Ooops! Sorry didn't mean it to come across like that... just meant that "pushing" with a muscle doesn't actually add any force to the equation! (unless you're in a tunnel and can push on the ceiling at the same time as pushing down with your feet!)...
sorry again!
Re: Bio Mechanical Suspension systems
Posted: 05 Dec 2008, 00:25
by tomislavp4
It´s ok if it wasn´t on purpose
The video clearly shows what I meant in my first post
tomislavp4 wrote:if you could stiffen the shockabsorber (your muscle) on that wheel you´ll experience no roll

No roll=no camber change
By the way good video, ciro!
Re: Bio Mechanical Suspension systems
Posted: 05 Dec 2008, 01:02
by machin
It´s ok if it wasn´t on purpose
worse than that.... I didn't read your first post properly
Note to self: read previous posts properly first!
Re: Bio Mechanical Suspension systems
Posted: 05 Dec 2008, 04:21
by fastback33
Ahhh bummer, well, it was worth a shot....
Re: Bio Mechanical Suspension systems
Posted: 07 Dec 2008, 02:18
by Conceptual
machin wrote:The rules of physics I'm afraid scupper this... any force needs an equal an opposite force to balance it... that's just the way it is... so you can't push down constantly with anything unless you have something to push against.... e.g. can you push down with your feet whilst standing still? You can momentarily push down harder (i.e. at the start of a jump) but this is followed soon after by you leaving the ground.. this isn't a good situation for a car!
Same applies during corning..... so you can't get something for nothing.....
Is it possible to cantilever a downforce generating wing, and apply the downforce across a lever and fulcrum to increase the effect?
Re: Bio Mechanical Suspension systems
Posted: 07 Dec 2008, 03:06
by Jersey Tom
Nope. Force balance trumps all.
Aero DF + weight = the load on the wheels. Regardless of what kind of levers or muscles or cantelevers or whatever you want.
Re: Bio Mechanical Suspension systems
Posted: 07 Dec 2008, 03:24
by Conceptual
So, hypothetically, if I have a 10 inch wide wing mounted on the nose, it would produce the same amount of downforce as the same 10 inch wing mounted to a horizontal pylon 20 inces to one side of the nose?
Sorry for the off topic, but I have been wondering about this for a long time...
Re: Bio Mechanical Suspension systems
Posted: 07 Dec 2008, 03:50
by Ciro Pabón
Yes, they would, Conceptual. In the second case, you have the same vertical force (Fy), because you
have to have a balance of forces, as Jersey Tom mentions.
You'll have 5 times the torque (Mz) on the point where the wing is joined to the nose, because the distance goes from 5 inches (if, as it seems logical, the force is applied in the middle of a symmetrical wing) to 25 inches (because of the extra 20 inches of the pylon). Something like this:
That extra-torque doesn't give you more vertical force, because (I presume) is balanced by the wing at the other side of the car. Of course, if you do it only for one "half" wing, then you end with more vertical force, but just on one side of the car. It could be of any use only in an oval.
What you say it's true, JTom, but only for "static" balance. There are four wheels (duh), each with different load. That's the idea of sway bars: to get something from nothing, by eliminating "peaks". Bose suspension gives you the same advantage: a better distribution of forces among the wheels.
