Automobile is a generally four-wheeled vehicle designed primarily for the transportation of passengers and usually powered by an internal combustion engine that uses a volatile fuel.
The modern automobile is a complex technical system with subsystems with specific design functions. Some of them are made up of thousands of components that have evolved from advances in existing technology. Such as electronic computers, high strength plastics, and new alloys of steel and non-ferrous metals. Some subsystems have emerged due to air pollution, safety laws, and competition between manufacturers worldwide.
With an estimated 1.4 billion people worldwide, cars have become the most important means of transport for families. About a quarter of this is in the United States, where more than three trillion miles travel each year. Hundreds of different models have offer to Americans in recent years, around half of them from overseas manufacturers. Manufacturers are increasingly introducing new designs to capitalize on their patented technological advances. With around 70 million newly built units worldwide per year, manufacturers have divided the market into many tiny segments that remain profitable.
We consider new technical developments the key to successful competition. All automobile manufacturers and suppliers have employed R&D scientists and engineers to improve the body, chassis, engine, transmission, control systems, safety systems, and emission control systems.
These outstanding technical advances are not without economic consequences. The average cost of a new American car increased between 1980 and 2001. This is due to mandatory emissions control safety and performance requirements (such as additional airbags and catalytic converters). In the following years, we implemented new requirements were repeatedly. The introduction of information technology was another factor that drove up car prices, which rose 29 percent between 2009 and 2019. It is on top of the consumer costs associated with technical improvements in fuel economy that reduced fuel purchases can offset.
The vehicle design is heavily dependent on its intended use. Vehicles for off-road use must be durable and straightforward systems with high resistance to heavy overloads and extreme operating conditions. In contrast, products designed for high-speed road systems with restricted access require more options for passenger comfort, higher engine power, and optimized high-speed handling and vehicle stability. The stability depends primarily on the weight distribution between the front and rear wheels.
The height of the center of gravity and its position to the aerodynamic center of pressure of the vehicle, the suspension characteristics, and the selection of the wheels to use for propulsion. The weight distribution depends primarily on the location and size of the engine. The usual practice with front engines takes advantage of the most easily achieved stability with this design. However, with the development of aluminum engines and new manufacturing processes, it has become possible to place the engine in the stern without compromising stability.
Automobile bodies are often classified based on the number of doors, seating, and roof structure. Car roofs are traditionally support by pillars on either side of the body. Convertible models with retractable soft tops rely on the post on the side of the windshield for upper body strength. As convertible mechanisms and glass panels are essentially non-structural. The glass surfaces have enlarge for better visibility and aesthetic reasons.
The high cost of new factory tools makes it impractical for manufacturers to produce unique designs every year. We were typically programming new methods in three to six years, with minor improvements generally occurring during cycling.