The article has been written after a lot of research on the internet and after referring various books and resources. Please feel free to e-mail me if you have any comments or suggestions regarding the same
- It’s made up of 80,000 components; if it were assembled 99.9% correctly, it would still have 80 things wrong with it!
- It can go from 0 to 160 kmph AND back to 0 in FOUR seconds!
- On track, it is faster than the speeds at which smaller planes take-off for flight!
- In dry weather, the peak optimum operating temperature of its tyres is between 900 and 1200 degrees centigrade.
By now you’re probably thinking that these are quite impressive statistics. As you have rightly imagined, stats like these are not easy to get. Formula One teams spend an insane amount of time and money to ensure that the cars they create stand the best possible chance at surviving the conditions on a race track.
How exactly, though, is it all done? The race day performance of an F1 car is already decided at the design stage and a lot of work goes into the development of the car. Let’s take a quick look into the birthing of a Formula One Race Car. As the complete article would be quite enormous, let us take a look at the most fundamental structure of any vehicle, the chassis.
Back in the day, racing cars were made up of the same things as a normal road car. The onset of the 1980’s saw a revolution of sorts, and thus began the age of the carbon fibre composites. This material has four major advantages over other materials used in building the chassis. It’s lightweight, super strong, super stiff and can be moulded into all kinds of different shapes reasonably easily.
Let’s take a quick look at how exactly the chassis is manufactured.
a) Designed, analysed and developed by CAD and FEA software’s, solid epoxy patterns for the chassis are cut using five axis milling cutters, which read data from the CAD file and replicate the required dimensions. Epoxy is used instead of metal to ensure that when the moulds are undergoing curing at high temperatures, the effects of thermal expansion are minimized.
b) Female moulds are made from these patters. Upper and lower moulds are produced, as the chassis itself is manufactures in upper and lower halves which are then bonded together. This work is carried out in a ‘clean room’, which is effectively a room sealed off from surrounding environments using double-door airlocks.
c) The chassis themselves are manufactured from layered carbon-fibre cloth. The orientation of the fibre ‘plies’ (layers) is critical and they must run in specific directions according to the required stiffness properties of the structure. The number of plies and their orientation varies at different locations around the chassis. To ensure that the plies are correctly positioned, the staff carry out the lay-up work (layering of various carbon fibre plies) with reference to printed manuals containing annotated visual description to be followed for each ply. This is then rechecked before moving to the next step.
d) The whole assembly is then placed in a vacuum bag and pushed into an autoclave (a large oven that provides thermal curing with precise control of temperature and pressure). The resin then cures, thus fusing all the plies together to create a single solid half of the chassis. The completed chassis halves are removed from the moulds, and are bonded together to form the final monocoque.
e) Final machining and trimming of the finished chassis is carried out to produce any required detailing and to accommodate suspension pick-up-points, component mountings etc.
f) Throughout the preceding steps, rigorous inspection procedures are followed at every stage. Parts are also returned for inspection between on-track events and many parts have specified service schedules which may include NDT of bonded joints and the condition of laminates, stiffness testing, visual checking and cleaning/tidying up processes.
The above two pictures show the chassis of the LOTUS under construction and an Finite Elemental Analysis (FEA) of the stress distribution around the chassis
Although these steps provide a simplified view, the basic principles and procedures apply to all carbon-fibre components on the car. The main components of the chassis are the survival cell, the roll structures, the fuel tanks and ballasts.
The Survival Cell: The driver survival cell is an important feature. Apart from providing the driver with an extremely strong cocoon, the survival cell incorporates impact and rollover structures. The survival cell also incorporates side-impact-protection panels to reduce chances of parts of another car, punching through the side of the chassis and causing injury to the driver.
Roll Structures: In the event that the car becomes inverted during an accident, the FIA have specified that all cars must have two roll structures which must be incorporated into the chassis. The drives helmet and steering wheel must fall below a specified distance below the line drawn between the highest points of the two roll structures. Both Roll structures are subjected to load tests as part of the FIA regulations.
Fuel Tanks: The fuel tank is located in the chassis to the rear of the cockpit, behind the driver’s seat. It is made from an elastomer-impregnated Kevlar material which is light and extremely flexible. The fuel talk is designed to deform if subjected to high-energy impact. The fuel pumps are carefully designed to ensure that every last drop of fuel inside the tank is used up.
Ballast: The FIA specifies a minimum weight limit of all cars taking part in a Formula One race. Thus, the teams ensure that the car is designed in such a way that it is at least 40-50 kg lighter than the weight limit. The remaining weight is provided in terms of ballasts. The ballasts are simple structures whose function is to distribute the weight around a car as desired. There is no restriction on the materials that can be used as Ballasts. Red Bull Racing, for example, made the use of Tungsten.
The chassis for any new car must undergo a series of FIA crash tests, all of which must be passed before the chassis is homologated and the car is allowed to race. The impact test is usually carried out at the Cranfield Impact centre near Bedford, with an FIA witness present. Various tests are carried out, divided into impact tests, roll-structure tests and push-off tests.
The chassis design is only a small part of the overall development process involved for an F1 car. The aerodynamics, safety equipment, hydraulics, electronics etc. constitute a large amount of money and work-force. And with the advent of newer forms of technology every day, the design and development process in F1 is sure to become even more rigid and sophisticated.