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Re: Return of active suspension - 2017

Posted: 17 Jul 2014, 15:25
by Thunder
This article states the Teams already use active suspensions for their straight Line Tests. If that's true the cost Factor of having it allowed from 2017 on would be a big chunk smaller on top of Teams already stating it would be cheaper.

http://www.jamesallenonf1.com/2014/07/g ... -f1-tyres/

Re: Return of active suspension - 2017

Posted: 17 Jul 2014, 15:33
by Holm86
WaikeCU wrote:How much difference is there between Active Suspension and FRIC? Can you say that FRIC is part of Active Suspension, but FRIC isn't Active Suspension?
I would say all the difference. Active Suspension is exactly that. Active. It is digital and adjusted by computers. FRIC is completely passive and mechanical.

Re: Return of active suspension - 2017

Posted: 17 Jul 2014, 17:25
by FW17
The new active suspension of 2017 is not going to be anything like the 1993 type.

As per CW, it is going to be a system with simple suspension functions, with no active ride controls which influences aero.

I think it will be more along the lines of the ferrari electro magnetic suspension which were used some time in the last 10 years for finding the best mechanical set up.

Re: Return of active suspension - 2017

Posted: 17 Jul 2014, 21:50
by DaveW
Pierce89 wrote:The inerter gains grip because it reduces oscillation of tire load. What this means is your minimum tire load will be higher so its harder to lose grip.

DaveW please help here. Your multimagic is needed for an explanation.
Mmm. Not sure about that.

However, for what its worth, an inerter fitted (hypothetically) to the front axle of a race car (a GP2 in my example), will increase the minimum load at the front axle up to a point, hence increasing "grip". Here is my example.

The plot show the minimum, mean and maximum values of vertical load under the front wheels whilst the vehicle is being subjected to a swept frequency vertical input. That shown in red is with no inerter, with the minimum value occurring at the heave mode. Those shown in green, blue and black are for increasing values of inerter mass.

Heave mode control is successively improved with each increase in inerter mass, but at higher values of mass another mode intrudes, and becomes dominant. The new mode is actually the unsprung mass (hub) mode. The interesting fact about the inerter is that the overall power dissipated by the front tyres increases with inerter mass.

Hence there is a balance to be made between the improvement in heave mode control, loss in control of the hub mode, and the heat generated by the power dissipated by the tyres (front tyre temperature is often an issue).

Re: Return of active suspension - 2017

Posted: 17 Jul 2014, 22:37
by DaveW
WilliamsF1 wrote:The new active suspension of 2017 is not going to be anything like the 1993 type.
I think that is a given, although a system based on Frank Dernie's patent (see here) would probably work with the current SECU, I think.
WilliamsF1 wrote:As per CW, it is going to be a system with simple suspension functions, with no active ride controls which influences aero...
Seriously, I don't think that idea is feasible, for all kinds of reasons. For example, a GP2 suspension is about as simple as it comes, and that certainly influences aero - and aero influences the suspension set-up.
WilliamsF1 wrote:I think it will be more along the lines of the ferrari electro magnetic suspension which were used some time in the last 10 years for finding the best mechanical set up.
I have listened to Dominic Harlow's interview (straight line tests), but can't really comment, except to say that there was no requirement to use the SECU... I guess that would also be true of the Ferrari system (however unlikely that is).

Re: Return of active suspension - 2017

Posted: 18 Jul 2014, 02:16
by bill shoe
DaveW wrote: However, for what its worth, an inerter fitted (hypothetically) to the front axle of a race car (a GP2 in my example), will increase the minimum load at the front axle up to a point, hence increasing "grip". Here is my example.

The plot show the minimum, mean and maximum values of vertical load under the front wheels whilst the vehicle is being subjected to a swept frequency vertical input.
Great bit of data.

A bit off topic-- The horizontal axis is labeled "X-parameter". Is this frequency, time, or intentionally undisclosed? The numbers seem too high to be frequency in hertz, but I'm really not familiar with modern racecar setups.

Maybe more on topic-- For a shaker-rig vertical frequency sweep, would adding mass to the front corners (with no inerter) achieve a result that was similar to using an inerter?

Re: Return of active suspension - 2017

Posted: 18 Jul 2014, 08:56
by SectorOne
What sort of features can we expect that the suspension will do?

Anti-dive during braking?
Lean into corners?
Always maintain a near perfect distance from the ground?

Re: Return of active suspension - 2017

Posted: 18 Jul 2014, 09:17
by DaveW
bill shoe wrote:The horizontal axis is labeled "X-parameter". Is this frequency, time, or intentionally undisclosed? The numbers seem too high to be frequency in hertz, but I'm really not familiar with modern racecar setups.
Apologies, I was not trying to hide anything. The horizontal axis is time. Here is an alternative plot of the same data showing the frequency response of CPL per unit road acceleration.
bill shoe wrote:For a shaker-rig vertical frequency sweep, would adding mass to the front corners (with no inerter) achieve a result that was similar to using an inerter?
Adding the equivalent mass to the front wheels produced this for the first (lowest inerter mass) case. Not the same thing at all....

Re: Return of active suspension - 2017

Posted: 18 Jul 2014, 09:52
by DaveW
SectorOne wrote:What sort of features can we expect that the suspension will do?
An active system will driven by measurements, none of which is perfect. That reality has important consequences.

So, for example, one of the most important parameters would be load. I believe that PRL cells drift (vary with temperature) and are sensitive to more than just the vertical component of load. Hence they must be manipulated before they can be used to drive the suspension. Adding the ability to remove acceleration effects comes for free.

The same to be said about other measurements.... I could rabbit on for ever, but I will leave it at that for now.

Re: Return of active suspension - 2017

Posted: 18 Jul 2014, 10:21
by FW17
SectorOne wrote:What sort of features can we expect that the suspension will do?

Anti-dive during braking?
Lean into corners?
Always maintain a near perfect distance from the ground?

Probably none of that. Might not even be active in qualifying and race. A system with hydraulics which helps find a good setup with probably a few adjustments from the driver like the movable front wing.

Re: Return of active suspension - 2017

Posted: 18 Jul 2014, 11:09
by CBeck113
SectorOne wrote:What sort of features can we expect that the suspension will do?
I think that this is the right question. They have many ways which they could go, but since it is supposed to be cheap, here's my guess / thoughts (leaning way out the window here, just trying to lure a statement from Dave here :mrgreen: ):

* Traditional suspension (springs & dampers) will remain
* Inputs from the suspension will be travel, temperature & pressure
* Brakes, steering, temperature & speed the other inputs
* Central processing on an FIA ECU
* Individual actuators for each corner - meaning only data shared between the "wheels" (German has a word for teh suspension construction for a single wheel (Aufhängung), I can't find an appropriate one in English though - any suggestions?) - this is the major difference to FRIC. I don't think that they will group the axles, but I could be wrong, if the actuators are too heavy...

Anyone else?

Re: Return of active suspension - 2017

Posted: 18 Jul 2014, 12:00
by SectorOne
So the theorized system you guys think will be on the cars is more or less nothing like what the Williams was running?
(i can confess i don´t know anything about how the Williams system worked)

Re: Return of active suspension - 2017

Posted: 18 Jul 2014, 12:13
by FW17
SectorOne wrote:So the theorized system you guys think will be on the cars is more or less nothing like what the Williams was running?
(i can confess i don´t know anything about how the Williams system worked)

There is zero chance of seeing the active ride system of 1993 Williams returning.

Re: Return of active suspension - 2017

Posted: 18 Jul 2014, 12:57
by SectorOne
And that is because of costs entirely or is there another reason?

Re: Return of active suspension - 2017

Posted: 18 Jul 2014, 13:30
by FW17
SectorOne wrote:And that is because of costs entirely or is there another reason?
Cost has nothing to do with it.

It is FIA's fascination/obsession to reduce down force (or rather make down force expensive) that we will not see active ride controls (which almost entirely aims at stabilizing aero of the car in a simple manner) incorporated into the new active suspension system.