Terms used to describe early
Vehicle body styles
In the history of the motor car there has been some
ambiguity in the names used to describe various
types of body styles, built by coach builders from
different countries. The following terms relate to
the vehicles produced during the period 1895 to
1915, and show the derivation of the terminology
used to describe the modern vehicle.
Berlina Rarely used before the First World War.
A closed luxury car with small windows which
allowed the occupants to see without being seen.
Cab A term taken directly from the days of the
horse-drawn carriages. Used to describe an enclosed
vehicle which carried two passengers, while the
driver was situated in front of this compartment and
unprotected.
Cabriolet Used towards the end of the period.
Describes a car with a collapsible hood and seating
two or four people.
Coupé A vehicle divided by a fixed or movable
glass partition, behind the front seat. The driver’s
position was only partially protected by the roof
whilst the rear compartment was totally enclosed
and very luxurious.
Coupé cabriolet or double cabriolet A long vehicle
having the front part designed as a coupé and the rear
part designed as a cabriolet. There were often two
supplementary seats.
Coupé chauffeur A coupé with the driving position
completely covered by an extension of the rear roof.
Coupé de ville A coupé having the driving position
completely open.
Coupé limousine A vehicle having a totally
enclosed rear compartment and the front driving
position closed on the sides only.
Double Berlina A longer version of the Berlina
but having the driving position separated from the
rear part of the vehicle.
The history, development and construction of the car body 11
Double landaulet A longer version of the landaulet.
It had two permanent seats plus two occasional
seats in the rear and a driving position in front.
Double phaeton A phaeton which had two double
seats including the driver’s seat.
Double tunneau A longer version of the tonneau
in which the front seats were completely separated
from the rear seats.
Landau A cabriolet limousine having only the
roof behind the rear windows collapsible.
Landaulet or landaulette A small landau having
only two seats in the closed collapsible roof
portion.
Limousine A longer version of the coupé with
double side windows in the rear compartment.
Limousine chauffeur A limousine with an extended
rear roof to cover the driving position.
Phaeton A term from the days of the horse-drawn
carriage. In early motoring it was used to describe
a lightweight car with large spoked wheels, one
double seat and usually a hood.
Runabout An open sporting type of vehicle with
simple bodywork and two seats only.
Tonneau An open vehicle having a front bench
seat and a semicircular rear seat which was built
into the rear doors.
Glass saloon A large closed vehicle similar to a
double Berlina but with enlarged windows.
Saloon A vehicle having the driving seat inside
the enclosed car but not separated from the rear
seat by a partition.
Torpedo A long sports vehicle having its hood
attached to the windscreen.
Victoria Another term derived from the era of
horses. The Victoria was a long, luxurious vehicle
with a separate driving position and a large rear
seat. It was equipped with hoods and side screens.
Wagon saloon A particularly luxurious saloon
used for official purposes.
Vehicle classification
There are many ways in which motor vehicles may
be classified into convenient groups for recognition.
Much depends on such factors as the manufacturer,
the make of the car, the series and the body type
or style. Distinctive groups of passenger vehicle
bodies include the following:
1 Small-bodied mass-produced vehicles
2 Medium-bodied mass-produced vehicles
3 Large-bodied mass-produced vehicles
4 Modified mass-produced bodywork to give a
standard production model a more distinctive
appearance
5 Specially built vehicles using the major components
of mass-produced models
6 High-quality coach-built limousines (hand made)
7 Sports and GT bodywork (mass-produced)
8 Specially coach-built sports cars (hand made).
Styling forms include the following:
Saloon The most popular style for passenger
vehicles is the two-door or four-door saloon. It has
a fully enclosed, fixed-roof body for four or more
people. This body style also has a separate luggage
or boot compartment (Figure 1.6a).
Hatchback This body style is identified by its
characteristics sloping rear tailgate, which is classed
as one of the three or five doors. With the rear seats
down there is no division between the passenger and
luggage compartments and this increases the luggage
carrying capacity of the vehicle (Figure 1.6b).
Estate This type of vehicle is styled so that the
roof extends to the rear to give more luggage
space, especially when the rear seats are lowered
(Figure 1.6c).
Sports coupé and coupé A sports coupé is a
two-seater sports car with a fixed roof and a highperformance
engine. A coupé is a two-door, fixedroof,
high-performance vehicle with similar styling
but with two extra seats at the rear, and is sometimes
referred to as a ‘2-plus-2’ (Figure 1.6d).
Convertible or cabriolet This can have either two
or four doors. It has a soft-top folding roof (hood)
and wind-up windows, together with fully enclosed
or open bodywork (Figure 1.6e).
Sports This is a two-seater vehicle with a highperformance
engine and a folding or removable
roof (hood) (Figure 1.6f).
Limousine This vehicle is characterized by its
extended length, a high roofline to allow better
headroom for seating five passengers comfortably
behind the driver, a high-quality finish and luxurious
interiors (Figure 1.6g).
The evolution of design
When the first motor cars appeared, little attention
was paid to their appearance; it was enough
that they ran. Consequently the cars initially sold
12Repair of Vehicle Bodies
Figure 1.6Vehicle styling forms: (a) saloon (b) hatchback
The history, development and construction of the car body 13
Figure 1.6(c) estate (d) coupé (e) convertible
14Repair of Vehicle Bodies
Figure 1.6(f) sports (g) limousine
to the public mostly resembled horse-drawn carriages
with engines added. Henry Ford launched
his Model T in 1908, and it sold on its low price
and utility rather than its looks. However, the
body design of this car had to be changed over
its 19 year production span to reflect changes in
customer taste.
The 1930s saw greater emphasis on streamlining
design. Manufacturers began to use wind
tunnels to eliminate unnecessary drag-inducing
projections from their cars. One of the dominant
styling features of the 1950s and 1960s was the
tail fin, inspired by the twin tail fins of the
wartime Lockhead Lightning fighter aircraft.
Eventually a reaction set in against such excesses
and the trend returned to more streamlined
styling.
In creating cars for today’s highly competitive
car market, designers have to do far more than just
achieve a pleasing shape. National legal requirements
determine the positions of lamps, direction
indicators and other safety-related items, while
the buying market has become much more sophisticated
than before. Fuel economy, comfort, function
and versatility are now extremely important.
1.2 Creation of a new design from
concept to realization
The planning, design, engineering and development
of a new motor car is an extremely complex
process. With approximately 15 000 separate parts,
the car is the most complicated piece of equipment
built using mass production methods.
The history, development and construction of the car body 15
Every major design project has its own design
team led by a design manager, and they stay with
the project throughout. The size of the team varies
according to the progress and status of the project.
The skill and judgement of the trained and experienced
automotive designer is vital to the creation of
any design concept.
To assist in the speed and accuracy of the ensuing
stages of the design process (the implementation),
some of the most advanced computer-assisted
design equipment is used by the large vehicle
manufacturers. For example, computer-controlled
measuring bridges that can automatically scan
model surfaces, or machines that can mill surfaces,
are linked to a computer centre through a highly
sophisticated satellite communication network.
The key terms in computer equipment are as
follows:
Computer-aided design (CAD) Computer-assisted
design work, basically using graphics.
Computer-aided engineering (CAE) All computeraided
activities with respect to technical data processing,
from idea to preparation for production,
integrated in an optimum way.
Computer-aided manufacturing (CAM) Preparation
of production and analysis of production
processes.
Computer-integrated manufacturing (CIM) All
computer-aided activities from idea to serial
production.
The use of CAE is growing in the automotive industry
and will probably result in further widespread
changes. Historically, the aerospace industry was the
leader in CAE development. The three major motor
companies of GM, Ford and Chrysler started their
CAE activities as soon as computers became readily
available in the early 1960s. The larger automotive
companies in Europe started CAE activities in the
early 1970s – about the same time as the Japanese
companies.
Each new project starts with a series of detailed
paper studies, aimed at identifying the most competitive
and innovative product in whichever part
of the market is under review. Original research
into systems and concepts is then balanced against
careful analysis of operating characteristics, features
performance and economy targets, the projected
cost of ownership and essential dimensional
requirements. Research into competitors’ vehicles,
market research to judge tastes in future years, and
possible changes in legislation are all factors that
have to be taken into account by the product
planners when determining the specification of a
new vehicle.
The various stages of the design process are as
follows:
1 Vehicle styling, ergonomics and safety
2 Production of scale and full-size models
3 Engine performance and testing
4 Wind tunnel testing
5 Prototype production
6 Prototype testing
7 Body engineering for production
Vehicle styling
Styling
Styling has existed from early times. However, the
terms ‘stylist’ and ‘styling’ originally came into
common usage in the automotive industry during
the first part of the twentieth century.
The automotive stylist needs to be a combination
of artist, inventor, craftsman and engineer, with the
ability to conceive new and imaginative ideas and
to bring these ideas to economic reality by using
up-to-date techniques and facilities. He must have
a complete understanding of the vehicle and its
functions, and a thorough knowledge of the materials
available, the costs involved, the capabilities of
the production machinery, the sources of supply
and the directions of worldwide changes. His
responsibilities include the conception, detail,
design and development of all new products, both
visual and mechanical. This includes the exterior
form, all applied facias, the complete interior, controls,
instrumentation, seating, and the colours and
textures of everything visible outside and inside
the vehicle.
Styling departments vary enormously in size
and facilities, ranging from the individual consultant
stylist to the comprehensive resources of
major American motor corporations like General
Motors, who have more than 2000 staff in their
styling department at Detroit. The individual
consultant designer usually provides designs for
16Repair of Vehicle Bodies
organizations which are too small to employ fulltime
stylists. Some act as an additional brain for
organizations who want to inject new ideas into
their own production. Among the famous designers
are the Italians Pininfarina (Lancia, Ferrari,
Alfa), Bertone (Lamborghini), Ghia (Ford) and
Issigonis (Mini).
The work of the modern car stylist is governed
by the compromise between his creativity and the
world of production engineering. Every specification,
vehicle type, payload, overall dimensions,
engine power and vehicle image inspire the stylist
and the design proposals he will make. Initially he
makes freehand sketches of all the fundamental
components placed in their correct positions. If the
drawing does not reduce the potential of the original
ideas, he then produces more comprehensive
sketches of this design, using colours to indicate
more clearly to the senior executives the initial
thinking of the design (Figure 1.7). Usually the
highly successful classic designs are the work
of one outstanding individual stylist rather than of
a team.
The main aim of the designer is to improve passenger
comfort and protection, vision, heating and
ventilation. The styling team may consider the
transverse engine as a means of reducing the space
occupied by the mechanical elements of the car.
Front-wheel drive eliminates the driveshaft and
tunnel and the occupants can sit more comfortably.
Certain minimum standards are laid down with
regard to seat widths, kneeroom and headroom.
The interior dimensions of the car are part of the
initial specifications and not subject to much modification.
Every inch of space is considered in the
attempt to provide the maximum interior capacity
for the design. The final dimensions of the interior
and luggage space are shown in a drawing,
together with provision for the engine and remaining
mechanical assemblies.
Ergonomics
Ergonomics is a fundamental component of the
process of vehicle design. It is the consideration of
human factors in the efficient layout of controls in
the driver’s environment. In the design of instrument
panels, factors such as the driver’s reach
zones and his field of vision, together with international
standards, all have to be considered.
Legal standards include material performance in
relation to energy absorption and deformation
under impact. The vision and reach zones are geometrically
defined, and allow for the elimination
of instrument reflections in the windshield.
Basic elements affecting the driver’s relationship
to the instrument panel controls, instruments, steering
wheel, pedals, seats and other vital elements in
the car are positioned for initial evaluation using the
‘Manikin’, which is a two- and three-dimensional
measuring tool developed as a result of numerous
anthropometric surveys and representing the human
figure. Changes are recorded until the designer is
satisfied that an optimum layout has been achieved.
Safety
With regard to bodywork, the vehicle designer must
take into account the safety of the driver, passengers
and other road users. Although the vehicle cannot
be expected to withstand collision with obstacles
or other vehicles, much can be done to reduce the
effects of collision by the use of careful design of the
overall shape, the selection of suitable materials and
the design of the components. The chances of injury
can be reduced both outside and inside the vehicle by
avoiding sharp-edged, projecting elements.
Every car should be designed with the following
crash safety principles in mind:
1 The impact from a collision is absorbed gradually
by controlled deformation of the outer
parts of the car body.
Figure 1.7Style artist at work (Ford Motor
Company Ltd )
The history, development and construction of the car body 17
2 The passenger area is kept intact as long as
possible.
3 The interior is designed to reduce the risk of
injury.
Safety-related vehicle laws cover design, performance
levels and the associated testing procedures;
requirements for tests, inspections, documentation
and records for the process of approval; checks that
standards are being maintained during production;
the issue of safety-related documentation; and
many other requirements throughout the vehicle’s
service life.
Primary or active safety
This refers to the features designed into the vehicle
which reduce the possibility of an accident. These
include primary design elements such as dual-circuit
braking systems, anti-lock braking systems, high
aerodynamic stability and efficient bad-weather
equipment, together with features that make the driver’s
environment safer, such as efficient through
ventilation, orthopaedic seating, improved all-round
vision, easy to read instruments and ergonomic
controls.
An anti-lock braking system (ABS) enhances a
driver’s ability to steer the vehicle during hard braking.
Sensors monitor how fast the wheels are rotating
and feed data continuously to a microprocessor
in the vehicle to signal that a wheel is approaching
lockup. The computer responds by sending a signal
to apply and release brake pressure as required. This
pumping action continues as long as the driver
maintains adequate force on the brake pedal and
impending wheel lock condition is sensed.
The stability and handling of the vehicle are
affected by the width of the track and the position
of the centre of gravity. Therefore the lower the
centre of gravity and the wider the track the more
stable is the vehicle.
Secondary or passive safety
If a crash does happen, secondary safety design
should protect the passengers by
1 Making sure that, in the event of an accident,
the occupants stay inside the car
2 Minimizing the magnitude and duration of the
deceleration to which they are subjected
3 Restraining the occupants so that they are not
injured by secondary impacts within the car,
and, if they do strike parts of the inside of the
vehicle, making sure that there is sufficient
padding to prevent serious injury
4 Designing the outside of the vehicle so that the
least possible injury is caused to pedestrians
and others who may come into contact with the
outside of the vehicle.
The primary concern is to develop efficient restraint
systems which are comfortable to wear and easy to
use. Manufacturers are now fitting automatic seatbelt
tensioners. These automatic ‘body lock’ front seatbelt
tensioners reduce the severity of head injuries by
20 per cent with similar gains in chest protection. In
impacts over 12 mile/h (20 km/h) the extra tension in
the seatbealt buckle triggers a sensor which tightens
the lap and diagonal belts in 22 milliseconds, that is
before the occupant even starts to move. In addition,
because it operates at low speeds, it covers a broad
spectrum of accident situations. Anti-submarining
ramps built into the front seats further aid safety by
reducing the possibility of occupants sliding under
the belt (Figure 1.8).
There are also engineering features such as
impact energy-absorbing steering columns, head
restraints, bumpers, anti-burst door locks, and selfaligning
steering wheels. Anti-burst door locks are
to prevent unrestrained occupants from falling out
of the vehicle, especially during roll-over. The
chances of survival are much reduced if the occupant
is thrown out. Broad padded steering wheels
are used to prevent head or chest damage.
Collapsible steering columns also prevent damage
to the chest and abdomen and are designed to
Figure 1.8Automatic seatbelt tensioner
(Vauxhall Motors Ltd)
18Repair of Vehicle Bodies
prevent the steering column being pushed back
into the passenger compartment whilst the front
end is crumpling. The self-aligning steering wheel
is designed to distribute force more evenly if the
driver comes into contact with the steering wheel
during a crash. This steering wheel has an energyabsorbing
hub which incorporates six deformable
metal legs. In a crash, the wheel deforms at the hub
and the metal legs align the wheel parallel to the
chest of the driver to help spread the impact and
reduce chest, abdomen and facial injuries.
Body shells are now designed to withstand major
collision and rollover impacts while absorbing
shock by controlled deformation of structure in the
front and rear of the vehicle. Vehicle design and
accident prevention is based on the kinetic energy
relationship of damage to a vehicle during a
collision. Energy is absorbed by work done on the
vehicle’s materials by elastic deformation. This
indicates that, to be effective, bumpers and other
collision-absorbing parts of a vehicle should be
made of materials such as foam-filled plastics and
heavy rubber sections. Data indicates that long
energy-absorbing distances should be provided
in vehicle design, and the panel assemblies used
for this purpose should have a lower stiffness than
the central section or passenger compartment of
the vehicle. The crumple zones are designed to
help decelerate the car by absorbing the force of
collision at a controlled rate, thereby cushioning
the passengers and reducing the risk of injury
(Figure 1.9). The safety cage (or safety cell) is the
central section of the car body which acts as the
passenger compartment. To ensure passenger
safety, all body apertures around the passenger area
should be reinforced by box-type profiles; seats
should be secured rigidly to the floor; and heavy
interior padding should be used around the dashboard
areas. A strengthened roof construction,
together with an anti-roll bar, afford additional
protection in case of overturning (Figure 1.10).
To counteract side impact manufacturers are now
fitting, in both front and rear doors, lateral side supports
in the form of twin high-strength steel tubular
beams, which are set 90 mm apart to reduce the risk
of the vehicle riding over the beams during side
collision. These beams absorb the kinetic energy
produced when the vehicle is struck from the side.
To further improve the body structure the BC-pillars
are being reinforced at the points of attachment to
the sill and roof, again giving more strength to the
safety cage and making it stronger and safer when
the vehicle is involved in collision (Figure 1.11a, b).
Visibility in design is the ability to see and be
seen. In poor visibility and after dark, light sources
must be relied upon. The lights on vehicles now
are much more efficient than on earlier models.
The old tungsten filament lamp has given way to
quartz-halogen lamps which provide much better
illumination. The quartz-halogen lamp is able to
produce a more powerful beam because the filament
can be made hotter without shortening its
lifespan. Hazard, reversing and fog lights are now
fitted to most vehicles to improve safe driving.
In daylight, colour is probably the most important
factor in enabling cars to be seen. If a vehicle is
coloured towards the red end of the spectrum, it can
be less obvious to other road users than a yellow
one, especially in sodium vapour street lights: a red
car absorbs yellow light from the street light and
Figure 1.9Crumple zones (Volvo Concessionaires Ltd )
The history, development and construction of the car body 19
reflects little, and so appears to be dark in colour,
whereas a yellow car reflects the yellow light and
appears more obvious. Silver vehicles will blend
into mist and fog and become difficult to see.
Blind spots can be diminished firstly by good
design of front pillars, making them slim and
strong, and secondly by reducing the area of rear
quarter sections. This elimination of blind spots is
now being achieved by using bigger windscreens
which wrap round the front A-post, and rear windows
which wrap round the rear quarter section,
giving a wider field of vision.
Many automotive manufacturers now believe that
a seatbelt/airbag combination provides the best
possible interior safety system. Airbags play an
important safety role in the USA since the wearing
of seatbelts is not compulsory in many of the states.
As competition to manufacture Europe’s safest car
Figure 1.10Safety cage (Volvo Concessionaires Ltd )
20Repair of Vehicle Bodies
(a)
Figure 1.11(a) Safety features included in the safety cage (Vauxhall Motors Ltd ) (b) Reinforced BC-pillar and
anti-roll bar (Volvo Concessionaires Ltd )
The history, development and construction of the car body 21
increases, more manufacturers including those in
the UK are starting to fit airbags. These Eurobags,
or facebags as they are now called, since their main
function in Europe and the UK is to protect the face
rather than the entire body in the event of collision,
are less complex than their USA counterparts.
The first automotive airbags were made more
than 20 years ago using nylon-based woven fabrics,
and these remain the preferred materials
among manufacturers. Nylon fabrics for airbags
are supplied in two basic designs depending on
whether the airbag is to protect the driver or the
front passenger. The driver’s airbag is housed in
the steering wheel and requires special attention
because of the confined space (Figure 1.12). The
passenger’s airbag system has a compartment door,
located in front of the passenger in the dash area,
which must open within 10 milliseconds and
deploy the airbag within 30 milliseconds. The vehicle
has a crash sensor which signals the airbags to
deploy on impact (Figure 1.13).
Production of models
Scale models
Once the initial designs have been accepted, scale
models are produced for wind tunnel testing to
determine the aerodynamic values of such a design.
These models are usually constructed of wood and
clay to allow for modifications to be made easily.
At the same time, design engineering personnel
construct models of alternative interiors so that
locations of instruments can be determined.
A or scale model is produced from the stylist’s
drawings to enable the stylist designer to evaluate the
three-dimensional aspect of the vehicle. These scale
models can look convincingly real (Figure 1.14).
The clay surfaces are covered with thin coloured
plastic sheet which closely resembles genuine painted
metal. Bumpers, door handles and trim strips are all
cleverly made-up dummies, and the windows are
made of Plexiglass. The scale models are examined
critically and tested. Changes to the design can be
made at this stage.
Full-size models
A full-size clay model is begun when the scale
model has been satisfactorily modified. It is constructed
in a similar way to the scale model but uses
a metal, wood and plastic frame called a buck. The
clay is placed on to the framework by professional
model makers, who create the final outside shape of
the body to an accuracy of 0.375 mm. The high
standard of finish and detail results in an exact
replica of the future full-size vehicle (Figure 1.15).
Figure 1.12Driver’s airbag system (Du Pont (UK) Ltd )
Figure 1.13Driver and front passenger airbag
systems in use (Du Pont (UK) Ltd )
22Repair of Vehicle Bodies
Figure 1.14Scale model maker at work (Ford Motor Company Ltd )
Figure 1.15Full-size clay model
(Ford Motor Company Ltd)
Figure 1.16Checking dimensional accuracy of the
full-size model (Ford Motor Company Ltd )
This replica is then evaluated by the styling management
and submitted to top management for their
approval. The accurate life-size model is used for
further wind tunnel testing and also to provide
measurements for the engineering and production
departments. A scanner, linked to a computer,
passes over the entire body and records each and
every dimension (Figure 1.16). These are stored
The history, development and construction of the car body 23
and can be produced on an automatic drafting
machine. The same dimensions can also be projected
on the screen of a graphics station; this is
a sophisticated computer-controlled video system
showing three-dimensional illustrations, allowing
design engineers either to smooth the lines or to
make detail alterations. The use of computers or
CAD allows more flexibility and saves a lot of
time compared with the more conventional drafting
systems.
At the same time as the exterior model is being
made, the interior model is also being produced
accurately in every detail (Figure 1.17). It shows
the seating arrangement, instrumentation, steering
wheel, control unit location and pedal arrangements.
Colours and fabrics are tried out on this
mock-up until the interior styling is complete and
ready for approval.