Suspension Efficiency

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hardingfv32
32
Joined: 03 Apr 2011, 19:42

Suspension Efficiency

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Is there a strategy that the teams might use to measure how well one wheel/corner is compiling (high frequency) with the track surface? I assume they have wheel inertia. load and displacement data for each corner available. How would you use this data?

Brian

Jersey Tom
166
Joined: 29 May 2006, 20:49
Location: Huntersville, NC

Re: Suspension Efficiency

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Do you mean actually measured at the racetrack? I would imagine they log damper displacement and pushrod load. On a seven post rig you can measure vertical load directly.

How would you use this information? One very general strategy might be as follows: As you put stiffer springs, etc. on a car you will incur more load variation and worse mechanical grip, however you may be improving your aero platform - there's a tradeoff. So you might work out several different package options and evaluate them on track to find if there's a best compromise in between. Or, you might work on things to maintain a ride height profile and improve load variation.

If you were to do this for long enough - a variety of cars, tracks, etc. you might start to find other trends that tend to yield performance. There are all sorts of ways of cutting up and boiling down the data - response frequencies, damping ratios, relative ratios of things front to rear or proportioned to tire size, various measures of position, velocity, acceleration. That's just data reduction. The key is having the experience and insight to know the characteristics and ranges that give you the performance you're after.
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hardingfv32
32
Joined: 03 Apr 2011, 19:42

Re: Suspension Efficiency

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Thank You
Brian

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godlameroso
309
Joined: 16 Jan 2010, 21:27
Location: Miami FL

Re: Suspension Efficiency

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One thing I never see talked about is toe curves, are they even an issue on F1 cars? Toe curves can do wonky things to tire life, heating and overall performance, and not in a good or bad way, but in wonky as in it does both good and bad things kind of way, and that the best settings can have profound effects. And also that the best setting may actually seem counter intuitive depending on the nature of the track.
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Greg Locock
233
Joined: 30 Jun 2012, 00:48

Re: Suspension Efficiency

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Suspension kinematics in general don't get discussed much. That may be because they obey Chapman's rule. Or it may be that the absolute priority is camber compensation. Or it maybe that the roll steer curve is so easy to adjust that it is routine.

Rustem 1988
0
Joined: 05 Sep 2017, 11:38

Re: Suspension Efficiency

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What suspension characteristics are important for fast and accurate response of the car when it turns?

Brenton
1
Joined: 17 Dec 2017, 07:28

Re: Suspension Efficiency

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Rustem 1988 wrote:
21 Feb 2018, 11:50
What suspension characteristics are important for fast and accurate response of the car when it turns?
Stiffer suspension is more responsive, but can reduce overall traction. Stiffer shocks, roll bars, etc.. Here's an informative link http://www.formula1-dictionary.net/set_ ... nical.html

Also here on f1technical: features/39

I recommend playing racing sims with a wheel. Play around with setup configuration once you get a good feel for the car. This can teach you a lot about what each suspension setting does. Nascar racing season 2003, Grand Prix 4, or newer ones like rfactor 2, iRacing, etc.. On GP4, the different feeling of stiff vs soft springs is really interesting, in terms of how responsive the car is to sudden steering input.

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machin
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Joined: 25 Nov 2008, 14:45

Re: Suspension Efficiency

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Greg Locock wrote:
06 Jun 2017, 00:56
Chapman's rule.
...which is???
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Greg Locock
233
Joined: 30 Jun 2012, 00:48

Re: Suspension Efficiency

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Any suspension will 'work' if you don't let it move.

I think he was referring to the way that people used to assume that stiff setup was faster than a soft one, all you are really doing is hiding the kinematic deficiencies of the suspension by suppressing all motion. Of course that all changed with aero.

Smokes
4
Joined: 30 Mar 2010, 17:47

Re: Suspension Efficiency

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Greg Locock wrote:
26 Feb 2018, 03:37
Any suspension will 'work' if you don't let it move.

I think he was referring to the way that people used to assume that stiff setup was faster than a soft one, all you are really doing is hiding the kinematic deficiencies of the suspension by suppressing all motion. Of course that all changed with aero.

If you don't let the suspension move how do stop the wheels treating every bump as a ski ramp?

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Tim.Wright
330
Joined: 13 Feb 2009, 06:29

Re: Suspension Efficiency

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Smokes wrote:
24 Jul 2019, 13:47
Greg Locock wrote:
26 Feb 2018, 03:37
Any suspension will 'work' if you don't let it move.

I think he was referring to the way that people used to assume that stiff setup was faster than a soft one, all you are really doing is hiding the kinematic deficiencies of the suspension by suppressing all motion. Of course that all changed with aero.

If you don't let the suspension move how do stop the wheels treating every bump as a ski ramp?
In F1 they did this by repaving all the tracks.
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e36jon
66
Joined: 25 Apr 2016, 02:22
Location: California, USA

Re: Suspension Efficiency

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Kind of crazy to remember, but it wasn't all that long ago that many F1 cars had completely fixed front or rear suspensions!

Just points out that the tires and then chassis flex are both significant parts of the total suspension equation.

We F1 fans don't often think of F1 cars as 'not very rigid in torsion', but compared to a modern tube-framed racing sedan/coupe (Australian Touring Cars, for instance) they are much softer. All that to say that the torsional chassis flex is also part of the suspension equation in F1.

Wild stuff.

Smokes
4
Joined: 30 Mar 2010, 17:47

Re: Suspension Efficiency

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Theoretically the most efficent way to transfer downforce to the tyre is to have a solid imcrompressible link from the downforce generator to the wheel. also by making the suspension solid you minmise shanges to the wheel base track width and camber which makes the car more stable till the tyres give up.

Jolle
132
Joined: 29 Jan 2014, 22:58
Location: Dordrecht

Re: Suspension Efficiency

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e36jon wrote:
24 Jul 2019, 18:31
Kind of crazy to remember, but it wasn't all that long ago that many F1 cars had completely fixed front or rear suspensions!

Just points out that the tires and then chassis flex are both significant parts of the total suspension equation.

We F1 fans don't often think of F1 cars as 'not very rigid in torsion', but compared to a modern tube-framed racing sedan/coupe (Australian Touring Cars, for instance) they are much softer. All that to say that the torsional chassis flex is also part of the suspension equation in F1.

Wild stuff.
Well, Williams did a test in a springless car somewhere in the early eighties when ground effect was in full swing. It not only made the car uncomfortable, it made it much slower. I at least can’t remember any raced car without suspension.

I think the optimum spring and damper setting is where you keep the weight on the tire as steady as possible and I assume they did this with active suspension. Just keeping the pressure on each corner level.

AJI
AJI
27
Joined: 22 Dec 2015, 09:08

Re: Suspension Efficiency

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e36jon wrote:
24 Jul 2019, 18:31
...it wasn't all that long ago that many F1 cars had completely fixed front or rear suspensions! ...
When? Certainly modern F1 cars have a lot of suspension travel. Perhaps not so much decades ago, but they weren't ever 'fixed'..?