Thursday, 10 July 2014

Making Sense of FRIC Suspension Ban and Pirelli Test

Following last weekends British Grand Prix, the teams stayed behind to complete an in season test on Tuesday and Wednesday this week. The main news to come from these days were the banning of FRIC (Front and Rear InterConnected) Suspension, and Pirelli testing a prototype set of 18 Inch wheels on an adapted 2014 Lotus car. This post will try to explain exactly what these are and the affect of Formula 1.

Charles Pic completed 14 laps on the experimental 18" Pirelli wheels.



Pirelli 18 Inch Wheel Test

For a number of years now, Formula 1 have used 13 inch wheels with large tyres whilst other motorsport series have moved to lower profile tyres. Finally though Pirelli have responded to constant query over lower profile tyres by trialling 18 inch wheels on Wednesday, with a view to their possible introduction in 2016 or 2017. Charles Pic ran 14 laps on them in a modified 2014 Lotus to accommodate the larger overall wheel size, but given how early in development Pirelli are he was told to stay off the kerbs and stayed within a limited straight line speed.

The goal was to try and run them and see how they react. The overall grip was very low, I think it was five or six seconds off the pace, mainly for the reason that the rest of the car was made for the normal tyre, not the prototype. It is true that they are more reactive and nervous, and then on top of that you lose a lot of aero. It is not even like you are in Monza configuration, it is even less because of this type of tyre. If you look at handling, of course it is not good - but that was not the point of the test. This was really the beginning with this type of tyre and for sure they will improve it. I think in the philosophy it will be a type of tyre that will react quickly, and the reaction you get in the steering wheel is more nervous. Each time you get the snap it is quicker.
His first impressions are interesting, however they also mean very little in relation to the end product if these are introduced in a couple of years time. The main thing that is directly comparable is the appearance of the larger wheels, which have been mixed from the reviews I have seen but leaning towards the positive. I wasn't sure seeing the pictures, but when moving I think they are a definite improvement.

 
Video was recorded by Daniel Bates

The teams will have a lot of work to do to get Formula 1 cars suited to the new tyres, starting almost completely from a blank canvas. As a result, car designs will also be best suited taking the "ground up" approach in the literal sense, with the tyres being the first form of suspension on the cars. The lower profile tyre means a smaller sidewall, which in turn means the tyre will have less "give" in it when going around corners. The suspension arms themselves will therefore need to do more of the work in order to produce a similar ride to current Formula 1 cars. The stiffer tyres will change the way engineers and drivers fine tune setup for both tyre pressures and camber as well, which again will need to compensate for the reduced flexibility in the tyres themselves. Finally,
the engineers will also need to find out the working temperature for the new tyres, and how to keep them at that temperature. This will see a large change in the way the brakes are arranged along with the axles and ducting that keeps the brakes from overheating, leading to aerodynamic tweaks as the teams direct airflow around or into the brakes and tyres.

Pirelli have come under a lot of fire for the way in which they have constructed their current tyres.

One final point of note is Pirelli's current contract as tyre supplier to the Formula 1 grid. Their current deal expires at the end of the 2016 season, having renewed of the back of a difficult year for the Italian company in 2013. It never seemed likely that a different supplier would be announced just 6 months before the first pre-season tests, but it was Michelin who looked closest to saving Formula 1 should Pirelli walk away from the sport or to at least join them as a joint supplier. Michelin have already made it clear that the only future they share with Formula 1 is with an introduction of 18 inch wheels, as they look to showcase their technologies rather than to artificially create a spectacle. It is an area where Formula 1 is already behind Formula E, a rising motorsport series that is set to grow in following dramatically if they can live up to their own promises. So with the introduction of low profile tyres, the debate would open up as to whether we were going to see Pirelli continue as the sole tyre supplier, Michelin step in and become the new supplier to all the teams, or a tyre war with both offering services... There are strong cases for all theories, and I'm sure they will develop alongside the tyres themselves.

Formula E test car complete with Michelin's low profile tyre, which they claim will operate in both wet and dry conditions.

FRIC Suspension Ban

News a little more out of the blue was the FIA's directive to all teams that FRIC (Front and Rear InterConnected) suspension systems are to be banned within Formula 1 from the German Grand Prix onwards. There is a possibility that the ban will be implemented for the start of the 2015 season instead, but that is only in the case where all current teams unanimously agree to the postponement. So what is FRIC suspension? In layman's terms, it is simply the joining of all the suspension components so that they work as one. It is done using hydrualics, and reservoirs as shown below.

A simplified diagram of a Formula 1 car and the FRIC suspension setup.

During a lap, a Formula 1 car is subjected to massive forces in order to accelerate, slow down and turn in the same way that a road car does. The suspension is a lot harder so the movement is far less, but the forces are also so much more (forces up to 5G around fast corners and under braking) at the speeds Formula 1 cars achieve. All of the movement upsets the aerodynamics and balance of the car, so the engineers want the car to be as stable as possible. Active suspension was introduced in Formula 1 do exactly the same thing but using complicated computers to analyse and react to what each corner of the car was doing. FRIC suspension is a passive system but a very simple one, in that hydraulic fluid is used to balance out the forces across the cars 4 corners. the result is a a more stable car if the teams are able to get the balance and timing of such a system correct.

FRIC suspension is believed to be one of the systems giving Mercedes their advantage in 2014.

The result of losing these systems could mean a number of factors for the teams, such as reduced mechanical grip leading to reduced performance. This will likely be Mercedes biggest fear, with reportedly the most advanced FRIC suspension on the grid (rumours were circled of the system back in 2012). For those using the system before, simulator work will be key before Germany to analyse and estimate how tyre degradation will be affected. Other design teams will be frantically looking over aerodynamic parts that only work when the body is kept stable by the system, as Formula 1 cars are always at the limits between working perfectly and failing. It should make the practice sessions ahead of the German Grand Prix very busy and testing times for the teams indeed.