This edition of F1 Forensics is brought to thejudge13 readers in partnership with SomersF1, Like most of us, Matthew Somerfield has a day job and his is being the manager of a car & van rental company in the Isle of Wight.
His passion is to try and bring us non-techies closer to F1 by bridging the gap between the full blown engineering publications and the simplicity of much that is provided by TV.
Before I hand over to Somers, I think a short introduction to the history of the effect Matt is talking about would be helpful.
A tuned mass damper, is a device mounted in structures to reduce the amplitude of mechanical vibrations. Their application can prevent discomfort, damage, or outright structural failure. They are frequently used in power transmission, automobiles, and buildings.
There is some F1 history to ‘mass damping’ and this article from F1Fanatic summarises the events well.
The biggest technical controversy of the 2006 season was the banning of Renault’s ‘tuned mass damper’ suspension system. It put Renault’s championship defence in jeopardy and seriously questioned the impartiality of the FIA. Many in the paddock suggested the governing body were trying to engineer a final championship victory for the retiring Michael Schumacher.
In a strange situation the FIA and their own stewards were at odds with each other over the system’s legality – which did little to persuade anyone that the banning of the system was fair. Renault began developing its mass damper late in 2005 and was used on the R25 in the last races of the season.
The system essentially consisted of a sprung weight enclosed within the car to dampen the pitching as it rode over bumps. Originally it was only used at the front of the car. As is common practice with new technologies, Renault supplied the FIA with details of the system. The governing body agreed it was safe and legal to use.
Renault’s 2006 challenger, the R26, was designed with the system in mind from its conception. For 2006 the mass dampers would also be fitted to the rear of the car. The dampers proved particularly beneficial on the Michelin-shod cars. Inevitably, other teams got wind of what Renault were doing and built their own copies. But none were able to find as much of a benefit from the system as Renault were.
At this point the politicking began. Renault made a strong start to 2006 and other teams questioned the legality of the dampers. The matter came before the stewards at the German Grand Prix who agreed that the system was legal.
Then, astonishingly, the FIA appealed against the stewards’ verdict. A date for a hearing was set following the next round in Hungary and Renault, wisely, opted not to run the mass dampers until further notice. At the Hockenheimring their drivers struggled home fifth and sixth while Ferrari romped to a one-two.
On August 23rd the FIA International Court of Appeal ruled Renault’s mass dampers illegal. They cited article 3.15 of the Formula One Technical Regulations – claiming the system constituted a moveable aerodynamic device.
This was surprising. Clearly, the device was internal and so did not have a direct aerodynamic effect. Indeed, it was hard to see how it was a moveable aerodynamic device any more than conventional suspension was.
Renault’s ire was compounded by the fact that the banning came during the summer testing ban, inhibiting their ability to test alternative parts. At the following round in Istanbul Ferrari raced with new extended brake fairings in the rear wheel hubs, which seemed like a much more obvious example of a moveable aerodynamic device.
Renault claimed the loss of the system cost them 0.3s per lap. Over the final races of the season Ferrari were decisively quicker than Renault, yet the French and Alonso hung on to win both championship battles ahead of Schumacher and Ferrari.
<So now we understand the history – and the fact that this kind of damping is illegal, Somers has some interesting thoughts on the RB9 and it’s possible legality.
Theorizing: Red Bulls Splitter/Stay imitating a Mass Damper?
Red Bull’s splitter was the topic of some debate at and beyond the Korean GP, I myself looked into the topic when many people on twitter quizzed me over the heat signature Mark Webber’s car was showing on the FOM’s new Thermal Imaging camera’s. In the case of Webber the FOM had decided to utilise a rearward facing camera due to the Hammerhead positioning of the camera housing on the RB9.
2 weeks after my initial post on the topic and on the eve of the Indian GP, fellow Tech analyst Gary Anderson weighed in on the topic lending credence to my original analysis. On the back of this it seems the FIA were also keen to allay any fears that Red Bull may be gaining an advantage from heating the Splitter. Michael Schmidt of German publication AmuS reported that the FIA conducted their own test (in India), heating the front of the Splitter to 300o before performing their usual deflection test on the scrutineering rig.
If you have read both mine and Gary’s pieces you’d likely have concluded that we both believed that Red Bull were circumnavigating the deflection test by allowing the Splitter to heat up on contact with the track, transferring the heat to the stay and buckling it. This would effectively allow the Rake of the car to be increased and invariably make gains in downforce from the larger expansion area available at the Diffuser.
The FIA’s test disproved this theory but something about the whole situation continued to irk me and so although I have a mounting pile of articles that I have to write, I have spent days trawling through Sutton Images collection and reviewing footage.
The thing that stood out to me the most when reviewing pictures of the RB9 was that the metal stay that forms the connection between the underside of the chassis and the splitter appears to be buckled. As you will see from the pictures below, the flexion shown in the Stay isn’t consistent and appears to move when the car is in motion.
This of course still sent me off down the wrong garden path being distracted by the heating of the Splitter by the titanium skids underneath and once again raising the question of whether heat played a role in the upward deflection of the Splitter (by virtue of the stay being buckled under heat). At this point I decided to take heat out of the equation (as the buckle remained a component of the Stay’s design even at rest) and look at why the team might want the Splitter to move, then it dawned on me…
Yes they did, however the Mass Dampers of 2005/06 consisted of a spring mounted within the nosecone that utilised a weight floated within it (around 9kg’s). The premise is that as the tyre deforms under load (without a Mass Damper) you lose both mechanical grip and downforce consistency. We have however all seen the slow motion replays in the past that show the amount of oscillation the tyres have as they ride kerbs, this oscillation has a frequency and if you were able to determine this frequency you could dampen it’s effects.The original Mass Damper’s employed in 05/06 were rumored to give a lap time advantage of around 3 tenths but 8 years on and re-designed who can guess what it would be worth? (Last time around we were in the middle of a tyre war with the Michelin runners gleaning a larger advantage than their Bridgestone counterparts)
I therefore propose that in the case of Red Bull the Stay acts like the spring in the Mass Damper whilst the Splitter is the weight required to make the spring act. How about the Splitter’s deflection test? I hear you say. Well the stay in itself is rigid and impervious to the 2000NM or 200KG’s of force placed upon it on the rig and must not deflect more than 5mm. What you will see in the following video though is that the stay whilst in motion however is resonating at a frequency that allows it to move beyond that 5mm. (Be warned you may have to watch the video several times to see the Stay buckling, also pay close attention to the fact that the stay buckles even though the plank/splitter doesn’t impact with the track. Moreover it seems to deflect in opposition to the tyre oscillation)
Matching the frequency of the tyres oscillation has a 2 fold effect:
Tyres: As the car corners and exerts load into the tyres they begin to slip, if you can delay this slip then not only should you be able to extract more grip (by virtue of a bigger contact patch) but you will also over a sustained period see less degradation.
Downforce: The damping of the chassis against the tyre deformation means that aerodynamically the car becomes more consistent, this of course means not only are Red Bull perhaps creating the most downforce on the grid, it isn’t being spoilt by the natural movement of the car.
The effects of resonance can be widesweeping and suffice to say that doing what I believe Red Bull have doing here would be beneficial in terms of both creating downforce and reducing drag. Having concluded that the Splitter is indeed in motion, albeit not being caused by the heat generated by the titanium skids transferring their heat into the upper face of the Splitter, we can now look at this with more certainty.
The FIA deflection test is conducted in order to ascertain whether the Splitter moves upward as it hits the ground. What of course isn’t tested is how much it droops when the stay resonates at the frequency of the tyres. The buckle that resides in the stay when it’s at rest allows the stay to deform at resonance therefore moving not only vertically but perhaps also horizontally pivoting in the opposing direction to the deforming tyres.
Lets think of the movements of the car as it enters a corner:
Braking: As the car decelerates the tyres deform, with the sidewall of the tyre squishing outward at the same time the stay would deform vertically, this also minimises the Splitter’s interaction with the ground (which due to Red Bull’s Rake angle it’s already in close proximity) allowing a consistent level of airflow to pass over and under the splitter an onward to both the Diffuser and driving the airflow around the Sidepods.
Turn In: Working in opposition to the tyres oscillation, the splitter and stay dampen the cars movements causing less rolling resistance and therefore hysteresis. As we know heat management of the Pirelli tyres is crucial in terms of degradation and so less hysteresis equals better degradation. As the tyres are having to perform less vertical work we can also assume that a net grip gain and loss of tyre slip is leveraged too.
Apex Speed: Less resistance from the tyre and chassis equates to a more stable car and results in the driver being able to carry more speed through the corner.
Top Speed: With the car able to carry much more speed throughout the cornering phase it’s therefore conducive to the car being able to attain a higher top speed. A peculiarity in the case of Red Bull who in terms of setup always tend to favour the generation of downforce. If you have been following my work this season though you’ll have undoubtedly noted how much Rear Wing angle the team have shed since the middle of the season. This is of course because downforce generated at the Rear Wing is ‘dirty’ and invariably comes with a much larger drag penalty than the downforce generated in the Diffuser. By reducing the wing angle and changing the gear ratios the team have been able to become fast not only in the corners but on the straights too.
So what was all that about with the Splitter heating up on the Thermal Imaging camera?
Red Bull as we know run an aggressive amount of Rake which means occasionally under braking etc the Splitter and the plank housed within it could contact the ground. If this were to occur over a sustained period it would mean the car would fail the post scrutineering check which allows 1mm of the plank to be worn away. The titanium skids are placed under the plank to stop this wearing from happening and in the case of Red Bull it appears the heat is then transferred into the upper surface of the Splitter and dissipated, like a heatsink. This is why we see the team putting drill marks in the upper surface too as it helps to increase the surface area and promote the direction in which they want the heat to dissipate.
If we were to look back at the history of the original Mass Damper’s in F1 we would of course know that Renault pioneered the device that was subsequently copied by others before the FIA banned it. It’s a name though that we really should turn our attention to; Rob Marshall, Red Bull’s Chief Designer pioneered the original Mass Damper when he worked at Renault. So it’s no wild stretch then for the team to take advantage on an area of the car that worked so well in the past and redesign it for the prevailing trend / regulations / technology available. If you’d like to cast your mind back to this time last year I also posed the same question on the aeroelasticity of Red Bull’s nose in creating a similar effect. Rarely in F1 do we truly see an new innovation, the boundary pushing is usually a team taking a pre existing idea and applying it a new way, this I believe is another case of just that.
So if they are doing it, is it legal?
Well only Charlie Whiting and the boys can truly determine that factor but as the Stay is allowable in the technical regulations and only need pass the upward 200KG deflection test on the rig I don’t see why it wouldn’t be. Although just like the original Mass Damper if it were to be found in use does it constitute a ‘Moveable Aerodynamic Device’? Red Bull could argue just like Renault did that the device is moreover there to stabilise the car through harmonic matching.
Why hasn’t X,Y,Z copied it?
Perhaps because they haven’t noticed it, someone has to start a revolution for there to be one in the first place… (Renault started the last one, in terms of Mass Dampers) or perhaps they have but just haven’t implemented it to the same level as Red Bull… Ferrari are their closest rivals who have a chance to, as they too run the metal Stay. Mercedes don’t utilise a Stay, whilst Lotus use a Carbon Fibre one.
I’m guessing Red Bull had the option to run this at the start of the season, then swiftly found that the tyre construction wasn’t conducive to it’s application or didn’t yield as large a result as on the 2012 construction tyres. As we can see below Red Bull actually utilised a different stay prior to the change of construction mid season.
Above: This is an image from Montreal so before the change of construction, we can see here that Red Bull are using a much thinner stay, plausibly to glean the same effect as there is a small buckle visible in the stay. However take a look at how the car is riding the kerb and it’s more likely the stay has done so purely under load.
Above: Furthermore it’s clear from this image that during Free Practice (Montreal) the team had a rig in place of the Stay. I’d suggest from the picture that this is an actuator capable of moving the splitter to assess any issues that could be created by using a harmonic stay.
As always I have tried to be as expansive as I can with the resources available to me. Perhaps if I had access to some of the footage used by the likes of the BBC/Sky I could make an even more compelling case. I await your call guys…. and as always I invite your comments.
EDIT 08/11/13 – 16.37pm
After the piece being live for several hours now I have the following bits to add that may also aid in any questions:
Above: As we can see during the build process the team are performing their own checks on the deflection of the Splitter, note the stay is buckled which would give it the freedom of movement I’ve talked about above
Above: As shown in the .GIF above the stay broke on Vettel’s car in Hungary, as pointed out by @Germyl barring Hungary Vettel has won 8 of the last 9 races, a coincidence?
EDIT: 09/11/13 10.00am
Those who have asked me why Red Bull would entertain doing such a thing when teams already utilise a legal form of this in the case of J-Dampers/Inerters:
You would be quite correct in your assessment that teams have since the banning of Mass Dampers utilized a legal version which allows Mass Damping in the form of J-Dampers/Inerters. On this basis I’d conclude that although these do a job of damping the deflection/oscillation of the tyres, can it be improved? We have all seen from slow motion replays of cars riding the kerbs just how much deflection/oscillation the tyre under goes. Perhaps Red Bull felt they could make gains with additional damping and thus this method was born.
EDIT: 09/11/13 17.44PM
After further analysis of the footage from Hungary both drivers (Seb & Mark) had broken stays at that GP for the race. Mark’s stay actually broke much earlier in the race resulting in the upper surface of the Splitter dissipating most of the black paint by the end of the race, through heat being transferred from the skids below. Perhaps this is what led to the FIA placing the thermal camera on the RB9 in subsequent races…. (I have also checked the post race technical report of which post race checks were only made to cars 5 and 16 which include the Skid Block thickness. This means even with broken Stays and more than likely at least in the case of Webber beyond the 1mm wear rate the cars were deemed legal)
Above: Mark Webber pits in Hungary and as we can see the stay has folded forwards, through constant contact with the track surface a big surface area of black paint is also missing from the top of the metal Splitter
It would appear that the Stay used at this GP obviously sufficient for the task at hand and this much thinner Stay was replaced by the time the team arrived back from the Summer break in Spa…
TJ13 comment: I did suggest very early this year that Red Bull were using some kind of active ride system – yet this seems a plausible version of that idea. In Thursday’s news we reported that Milton Keynes were strongly against the FIA monitoring F1 teams’ suppliers – and there is a very good reason for this.