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Self leveling suspension and FRIC

Self leveling suspension and FRIC

(OP)
Hullo to all,
especially to gt6racer2 and Tmoose, seems ironic that almost to the day 1 year ago I posted a query re interconnected suspension and I see that it is a bit of a controversey in F1 today.
I noticed in your reply, gt6 that you said to google FRIC and I didn,t, sorry, I don,t follow F1 as much as I used to [too technical!!!] but wondered if those that do would add a few comments and at the same time may I ask about "moving mass dampers" what they how did they work and why they were banned.
With thanks Golfpin

RE: Self leveling suspension and FRIC

Are you referring to the tuned mass dampers that Renault were using a few seasons back? best guess is that they were tuned to wheelhop and helped the car settle down after jumping a kerb. They were banned on the specious grounds that they were movable aerodynamic devices, which were banned at the time.

Cheers

Greg Locock


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RE: Self leveling suspension and FRIC

(OP)
Thanks for the prompt reply Greg.
I truly don,t know what vehicle it was in, I saw a schematic quite awhile back and did not pay too much attention as usual. Now I am very confused, what I recall seeing was a device in the nose of the car and therefore I doubt if it could have been influenced by air. So being banned under the "moving aero dynamic device" seems to be wrong, but then again it could be my interpretation of what I saw, anyone have a picture of said "mass damper"?
Further to the FRIC why or under which rule would this have been banned, again I think I saw that it to was possibly contravening the "moving aero dynamic aid" rule! How could pitch control, if that is the correct term, be deemed MADA. If that be the case why don,t the springs, a stupid example, be classified the same way?
Greg do you recall that you made a comment about the Mouton designed layout in the Morris 1100, that the layout was incorrect that it was incorrectly linked, but I do notice that the current FRIC lay out allows for front/left to right/rear coupling as opposed to left/rear to left front, as depicted in the Len Terry Alan Baker book, is this done perhaps by some form of Computer control?
Any thoughts comments greatly appreciated,
Golfpin

RE: Self leveling suspension and FRIC

(OP)
Thanks for the prompt reply Greg.
I truly don,t know what vehicle it was in, I saw a schematic quite awhile back and did not pay too much attention as usual. Now I am very confused, what I recall seeing was a device in the nose of the car and therefore I doubt if it could have been influenced by air. So being banned under the "moving aero dynamic device" seems to be wrong, but then again it could be my interpretation of what I saw, anyone have a picture of said "mass damper"?
Further to the FRIC why or under which rule would this have been banned, again I think I saw that it to was possibly contravening the "moving aero dynamic aid" rule! How could pitch control, if that is the correct term, be deemed MADA. If that be the case why don,t the springs, a stupid example, be classified the same way?
Greg do you recall that you made a comment about the Mouton designed layout in the Morris 1100, that the layout was incorrect that it was incorrectly linked, but I do notice that the current FRIC lay out allows for front/left to right/rear coupling as opposed to left/rear to left front, as depicted in the Len Terry Alan Baker book, is this done perhaps by some form of Computer control, what are the weight transfer implications vis avi front to rear as apposed to left to right as apposed to left rear to right front etc.
Any thoughts comments greatly appreciated,
Golfpin

RE: Self leveling suspension and FRIC

(OP)
Sorry about the double post administrators please see fit to remove as necc. also should have included link thread800348350. Mouton should read Moulton. Golfpin

RE: Self leveling suspension and FRIC

Hi, Sorry, been away a while. Greg correctly explains the FIA's "logic", but I believe the change is more driven to close up the field - as FRIC has been around for quite a while without objection. The real issue is that some teams really understood what could be done, and took advantage of it, others were not so capable.
If well understood and optimized, the system can be set up to "couple" the front/rear as a tuneable variable - ie you can make it act as front in, rear goes (or tries to go) in, or front in, rear goes ( or tries to go) out. The classic passenger car adoption was in/out, which promotes a flat attitude over wheel inputs such as a sleeping policeman - but accentuates brake dive. The opposite, in/in coupling can be used to reduce pitching due to body applied loads such as aero or braking and most folks tend to think of this latter method being used in F1 - but more can be done...
Why the coupling is important is that you can set it up to manage the car attitude as the aero loads change. For example, if the rear aero force grows at a greater rate with speed than the front (or rear is more softly sprung), using the rear drop in height to force a similar drop in front height will tend to keep the car level (in/in coupling). However, alternatively you could accentuate the pitch change due to aero - making the rear drop cause a rise at the front (in/out couping), reducing wing attack angle and hence down/force and drag.
This is where the system gets complicated as each track will benefit from different strategies - a point and shoot track might be best with in/out, to give low drag on the straights and big downforce during braking and in the turns - whereas a fast sweeping track would want in/in, giving a more stable platform. It's quite hard to change the set-up once at the track (physical components have to be changed), so the modelling has to be very accurate. I have seen some diagrams that hint at switchable coupling modes, but I don't see how that could be legal.

Why I suspect the FIA is banning it now is because Mercedes have it working too well and the racing is suffering, and/or the boys in red are complaining. ( Ferrari used FRIC too but they can't seem to make it work so well - so the ban to them is a good thing).

Andrew

RE: Self leveling suspension and FRIC

(OP)
Hi chaps, sorry about the lapse in the courtesy of a thank you for your input but am getting older quicker [apologies but I am more infamous for my oxymorons than for for auto ingen[ness]uity . Golfpin

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