The load of the chassis is supported by the frame which is subjected to static, dynamic, and oftenvarying loads. The vehicle frame should be capable of bearing all the stresses and should not faileven if the vehicle is overloaded.The biggest challenge when designing a vehicle is to maximise occupant space while being strongenough to withstand the energy involved in the event of a crash. The frame is not entirely rigid andin fact has some ‘crumple zones’ which give away first in crashes purposely to absorb the energyinvolved. This is also why ‘bull-bars’ are now being restricted from use in many parts of the country.The bull-bars may transfer energy away from crumple-zones, and the energies may reach the cabinspace. And they are also bad for pedestrian safety.An ideal frame would consist of the following features:1. It is sturdy and should not bend during cornering for stability.2. It has adequate crumple zones.3. Roof should protect the occupants in case a car rolls over.4. It can be used for more than one model in a company’s line-up for cost effectiveness.Most popular constructions involved in vehicle design are Body-on-frame and monocoque chassis.Monocoque chassis’ have gained more popularity due to their lighter weight, their handlingcharacteristics and the fact that they integrate the chassis and the frame and the body into a singleunit, thereby greatly reducing manufacturing costs.The vehicle body plays a vital role in vehicle design and aerodynamics. Many top-end performance-oriented machines use the body itself to generate huge amounts of downforce instead of a wing atthe back, the best example to support this statement is the Ford GT, which despite the fact that itcan reach tremendous speeds, does not need a big wing at the rear since the rear quarter-panels aredesigned in such a way that air flows over them from the sides, thereby creating downforce. Anotherexample is the Nissan GT-R, which too uses its body to generate ridiculous amounts of downforceinstead a huge wing at the back.