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Body
BODY The body is the first thing most people notice about a vehicle. Not many people will gaze admiringly at a vehicle and say: “Cor, look at the engine on that.” This chapter will look at the purpose of the vehicle body, examine different chassis and how they are made and provide descriptions of the various body parts. There is also a section on aerodynamics, a chunk on how to service the body and its components, as well as plenty of information about safety features Want a fit body? Then read this
Comfort and safety
Manufacturers want their vehicles to look attractive, otherwise they won’t sell. The purpose of the vehicle will influence its design; sports vehicles, for example, are low to the ground, have a wide chassis and are aerodynamic.
Modern vehicles provide high levels of passenger comfort and safety as standard. The latest materials and techniques are used to reduce the amount of noise reaching the passengers from the engine, transmission and road wheels. Safety measures include crumple zones, side impact bars and strengthened passenger areas, as well as airbags, self-tensioning seat belts, head restraints and laminated windscreens. Vehicle buyers can tell how safe a vehicle is by looking at its safety star rating. This system, known as the European New Vehicle Assessment
A vehicle body must: be designed for occupant comfort and safety; conform to emission regulations; accommodate the driveline and suspension; provide storage and carry loads; and allow access for maintenance and servicing.
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Programme (Euro NCAP), was started in the UK and is now backed by the European Commission as well as various other European countries’ governments. The highest rating is 5 stars. The tests have recently started to look more at pedestrian safety as well as the safety of those inside the vehicle.
Crumple zones Crumple zones are sections of the vehicle designed to reduce the force of the impact. The faster a vehicle decelerates, the greater the force. The deceleration starts as soon as the crumple zones starts to, well, crumple. This means deceleration starts a little earlier (we’re talking tenths of a second here, but they all count) and so the force applied to the vehicle is less. Another reason for using crumple zones is that the force caused by an accident needs to be sent elsewhere – you don’t want the passengers to be hit by that force. The bending and smashing of crumple zones uses energy, and any parts of the vehicle that fly off also take away some more force.
Crumple zone
The more force transmitted to the frame of the vehicle, the less that reaches the people inside the vehicle. Which is good. You don’t want the entire vehicle to collapse though, which is why special crumple zones in the front and rear are used along with a rigid frame to protect the passengers.
Passenger compartment
Crumple zone
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