Lotus's braking attitude compensator is now illegal

[ackzsel]

We would like to raise the nose of the car under braking without making a suspension 'adjustment'.

Can we do anything with the shock pressures? As they vary during operation, would this be a way around the no adjustment rule?

Brian

That sounds like a very elegant solution since it wouldn't require an extra slave cylinder, but wouldn't that classify as active suspension?

[flyboy2160]

Just like the spineless, flip-floppy, tree-hugging politicians they are, the FIA will reverse this halfway through the season - like they tried with blown diffusers - on the basis of 'safety.' after the teams have spent millions on it.....

[hardingfv32]

Yeh, but that does not stop us from having fun coming up with a solution on our own. It is not going to coat us anything when they ban it.

Brian

[xpensive]

Yeh, but that does not stop us from having fun coming up with a solution on our own. ....

Brian

I can't wait to see that happening.

[Richard]

I'm puzzled as to why this thread is saying the pushrods can't change length because of a ban on adjustment.

The only ban is that there can't be adjustment due to external force, other than the wheel loading.

The suspension can stretch and contradict as much as you want as long as the force is only derrived from the wheel movement.

[Richard]

I'm puzzled as to why this thread is saying the pushrods can't change length because of a ban on adjustment.

The only ban is that there can't be adjustment due to external force, other than the wheel loading.

The suspension can stretch and contract as much as you want as long as the force is only derrived from the wheel movement.

An active system is one where there is a force external to the suspension and wheel that intervenes, such as a computer, or a hydraulic pump, or a driver, or aerodynamic device. A simple way to conceptualise this point is to do a simple equilibrium or zero sum check. You take the enregy of the wheel on the track and then see that it is the same as the reultant internal energy in the suspension.

[Giblet]

Did you just quote yourself, and then respond to yourself in kind?

I think you have had enough internet for one day son

[strad]

As you get older you want to speak to the smartest person in the room, and sometimes, that's yourself. HAHAHAHAHAHAHAHA

[hardingfv32]

I'm puzzled as to why this thread is saying the push-rods can't change length because of a ban on adjustment.

That rule is very precise: No adjustments while moving.

Since this did away with the VERY common driver adjustable sway bar, I think you could assume this was the only concrete way to eliminate active suspension features.

So your goal is to get this done without an 'adjustment'. In the Lotus example, we seem to have a hydraulic slave cylinder in the same location you might find a ride height adjusting shim stack. So it is pretty hard to argue that changing the length of the push-rod with hydraulics is any different than using the shim stack.

Brian

[Richard]

Sorry about talking to myself, I was using a mobile and hit the wrong button to post before I had finished.

Brian - Nothing wrong with the strut changing length, for example a MacPhearson strut changes length due to wheel loading. The only difference with this is swapping the mechanical spring for a hydraulic connection. We know that hydraulic circuits are allowed in the suspension systems, as long as they are self contained within the system without any external inputs.

[xpensive]

What's the title of this thread anyway?

[Ian P.]

There isn't much really new about what Lotus is trying to achieve, basically an "anti-dive" component to the front suspension. What is unique is how they are doing it, hydraulically.
On Motorcycles, there have been many variations, Ribi Lever, brake actuated compression damping and geometry effects, Brittan and BMW for two. Not to mention side-cars from many years ago. It is the FIA rules and limitations that have prompted the Lotus approach. Ya-gotta Love it.

http://www.motorcycledaily.com/2011/01/ ... irca-1985/

The use of the hydraulic connection between the reaction of the caliper and the net effect on the push-rod provides easily adjusted (and damped) variations of the net effect. Simply brilliant.
Likely the biggest benefit will not be under braking, but the ability to run a softer front suspension and the effect on cornering, tyre life and turn-in. All this without dragging the bodywork on the pavement.
Can't wait to see this in action.

[hardingfv32]

Brian - Nothing wrong with the strut changing length, for example a MacPhearson strut changes length due to wheel loading. The only difference with this is swapping the mechanical spring for a hydraulic connection. We know that hydraulic circuits are allowed in the suspension systems, as long as they are self contained within the system without any external inputs.

A MacPhearson strut changes length during its normal function as a suspension component. Up until this point in time it has not been the case that a F1 push-rod changes length while in use on the track.

On the other hand you are correct to point out the use of linked hydraulic actuators. Maybe the precedent has already been set by the use of these other systems.

Brian

[hardingfv32]

It is the FIA rules and limitations that have prompted the Lotus approach.

What past FIA rules would have prevented the implementation of this system until now, 30 years after it was first used on motorcycles?

Brian

[WhiteBlue]

Brian - Nothing wrong with the strut changing length, for example a MacPhearson strut changes length due to wheel loading. The only difference with this is swapping the mechanical spring for a hydraulic connection. We know that hydraulic circuits are allowed in the suspension systems, as long as they are self contained within the system without any external inputs.

Actually powering by external devices is prohibited among other things.