Automobile

From Wikipedia, the free encyclopedia.

An automobile, usually called a car (an old word for carriage), is a wheeled, self-powered vehicle, meaning it carries its own engine. (An older term is motorcar, meaning motorised carriage.) It has seats for the driver and passengers.

The vehicle is designed to travel on roads, although some, notably sport utility vehicles, allow off-road driving. Roads and highways are shared with other traffic such as motorcycles, tractor trailer and farm implements. The typical vehicle has just an internal combustion engine and four wheels, although as of 2002 gas-electric hybrid engine powered cars have begun to enter the market. Other vehicles run on electricity and fuel cells. Three-wheeled automobiles have been built, but are not common due to stability problems.

Automobiles/cars come in configurations such as

• Bubble car
• Convertible
• Hatchback
• Sedan
• Sports coupé
• Coupé convertible
• Station wagon or Estate car
• Sport utility vehicles (SUVs)
• Pickup trucks
• Truck (or lorry)
• Van and minivan.

See car classification.

The first vehicles were steam engine powered, then electric vehicles were produced by a small number of manufacturers. Later on gasoline (petrol) and diesel engines were implemented.

While steam-powered vehicles were devised as the late 18th century, it is generally claimed that the first automobiles with an internal combustion engine, the first modern cars, were completed almost simultaneously in 1886 by German inventors working independently, Gottlieb Daimler on 3 July 1886 in Mannheim and later Karl Benz and Wilhelm Maybach in Stuttgart.

On November 5, 1895, George B. Selden was granted the first U.S. patent for an automobile.

The large scale, production-line manufacturing of affordable automobiles was developed by Henry Ford in the 1910s. Early automobiles were often referred to as 'horseless carriages', which gives some idea of their design.

Alternative fuels for the gasoline (or petrol) engine have been around for many years. During World War II, coal gas was used. Methanol and ethanol (alcohols) are used as petrol extenders in some countries, notably in Australia and the United States. Methanol is often used as a fuel for racing cars.

Automobiles have changed the world with the advent of personal rapid transit. The automobile had a particulary strong impact on America.

In many countries, plentiful supplies of natural gas have seen methane sold as compressed natural gas (CNG) and propane sold as liquified petroleum gas (LPG) alongside petrol and diesel fuels since the 1970s. While a standard automotive engine will run on these fuels, there are some performance differences, notably a loss of power, due to the slower combustion of the alternative fuels. The power loss can often be reduced or eliminated by retuning the engine ignition, or fitting an electronic dual fuel ignition system that compensates for the slower burning fuel. The need to equip filling stations and vehicles with pressure vessels to hold these gaseous fuels and the more stringent safety inspections means that they are only economical in high mileage vehicles or if there are installation incentives. They are most economical where petrol has high taxes and the alternative fuels do not.

The many varieties of automobile racing (also called motorcar racing) collectively constitute one of the most popular categories of sport in the world.

Safety

Accidents seem as old as automobile vehicles themselves. Joseph Cugnot crashed his steam-powered "Fardier" against a wall in 1770. The first recorded automobile fatality was Henry Bliss on September 13, 1899 in New York, New York.

Every year thousands of people are killed in traffic, either by crashing into something, or by being crashed into. Major factors in accidents include driving under the influence of alcohol or other drugs, inattentive driving, overtired driving, road hazards such as snow, potholes and animals, and reckless driving. Special safety features have been built into cars for years (some for the safety of car's occupants only, some for the safety of others):

• ABS, Anti-lock Braking System, which prevents the car from skidding
• Airbags, which inflate in a crash to cushion the blow of a head on the dashboard
• ESP, Electronic Skid Prevention.
• crumple zones, which buffers the impact when the car hits something
• seat belts (or safety belts), which keep a person from being thrown forward
• cage construction

There are standard tests for safety in new automobiles, like the EuroNCAP. Despite these technological advances, the death toll of car accidents remains high: about 40,000 people die every year in the US, a number which increases annually in line with rising population and increased travel (although the rate per capita and per mile travelled decreases steadily), and a similar number in Europe. A much higher number of accidents result in permanent disability.

Renewable energy and the future

With heavy taxes on fuel, particularly in Europe, tightening environmental laws in the United States, particularly in California, and the possibility of further restrictions on greenhouse gas emissions, work on alternative power systems for vehicles continues.

Nowadays diesel cars can use 100% pure biodiesel, a fuel made from vegetable oils.

Attempts at building viable battery-powered electric vehicles continued throughout the 1990s (notably General Motors with the EV1), but cost, speed and inferior driving range made them unviable.

Current research and development is centred on "hybrid" vehicles that use both electric and combustion (pollution) power, and longer-term efforts are based around electric vehicles powered by fuel cells.

Other alternatives being explored involve methane and hydrogen-burning vehicles, fuel cells, and even the stored energy of compressed air (see Air Engine).

Major possible subsystems of a standard automobile

• engine
  • carburetor or fuel injection
  • engine configuration (V8, V6, V12, straight four, six, eights, flat-fours and sixes etc).
  • engine management systems
  • exhaust system
  • ignition system
  • self starter
  • pollution control devices
  • turbo-chargers and superchargers
  • front engine
  • rear engine
  • middle engine

• drivetrain
  • transmission (gearbox)
    • manual transmission
    • automatic transmission
  • 2 Wheel Drive
  • 4 Wheel Drive
  • differential
    • limited slip differential
  • axle
  • Live axle

• brakes
  • disc brakes
  • drum brakes
  • anti-lock braking systems (ABS)

• wheels and tires

• steering
  • rack and pinion
  • Ackermann steering geometry
  • Castor angle
  • Camber angle
  • Kingpin

• suspension
  • MacPherson strut
  • wishbone
  • double wishbone
  • multi-link
  • torsion beam
  • semi-trailing arm
  • axle

• body
  • crumple zones
  • monocoque (or unibody) construction

• interior equipment
  • passive safety
    • seat belts
    • airbags
  • controls
  • seats
  • ancillary equipment such as stereos, air conditioning, cruise control, positioning systems, cup holders, etc.

Related articles

• armored car
• carpool
• crash
• diesel cycle; four-stroke cycle; two-stroke cycle; Miller cycle
• future of the car
• flying car
• list of automobile manufacturers
• parking meter
• parking ramp
• road
• Road Safety
• tank
• traffic law
• urban car
• Wankel rotary engine

External links

• EuroNCAP
• US Department of Transport Fatal Accident Statistics
• National Transportation Safety Board.
• What to expect after an auto accident.

Cars 1917 to 2003

2003 Saturn ION2 (left), 2003 Chevrolet Corvette
Larger version

1937 Chrysler Airflow, 2002 Chrysler PT Cruiser

1917 Hudson Phaeton Larger version	1934 Austin Berkeley Larger version
1967 BMC Wolseley 6/110 Larger version	2000 Ford Focus Larger version
1973 Australian Ford XB Falcon GT 351	1964 Chevrolet Biscayne