Computers
Since 1996, the computer has played an integral part of the automotive world. Originally put into production in 1978, a carburetor, called a closed-loop carb, made the first effort at intelligent control of the air and fuel mixture. Since then, government legislation has made the computer mandatory. Control computers can do the work that humans find tedious, uninteresting and tiresome. They can also do such functions much faster than humans. They are here to stay in the automotive industry. In a play on words, computer giant Intel has control of the market, though there are a few small competitive companies doing specialty applications.
On Board Computers (OBC)
All vehicles now have a minimum amount of computer intelligence in the form of at least diagnostics as required by law. Most have more, as many as 20 on board computers doing one or more specialized jobs. These specialty computers are called for the most part, microcontrollers. They are not unlike business or personal computers in that they do high speed math and various calculations. By definition, what makes them a computer (as opposed to a calculator or other "electronic device") is that they have the ability to do logic, or in a more down to earth description, make a decision. Each microcontroller has a CPU, memory, ALU (arithmetic logic unit) storage and a bus (interface) to the outside world. Since it has one or more specific jobs, the "software" to do those jobs is carried within the unit in a ROM section. The fact that it does one or more specific jobs is what makes it a microcontroller. Even though they are made to perform in very harsh environments, these units are very susceptible to damage and destruction by heat, cold, moisture, vibration, static and real electricity. Most often, they cannot be repaired and must be replaced. The replacement process is a time consuming and technical operation often involving testing each function and calibration of some variables.
OBD and OBD II - Because of the quantity of information on diagnostics, I have devoted an entire page on OBD and OBD II. Please take a look at it for more information.
ABS - Anti-lock braking systems use one or more embedded controllers, computers, to control the application of brakes for maximum braking action with minimum loss of control. Please see our section on brakes.
Navigation - Computer monitored and controlled navigation is made possible through GPS (global positioning systems) signals. Such signals are used for aircraft, military vehicles, satellites and marine critical uses. They range from simple longitude and latitude information to turn by turn instructions on a monitor screen or heads up display. Such systems also include fuel information for economy and quantity calculations, transmission information for speed and time to and from a point calculations, and outside road information sources to determine possible alternative routes. Accuracy can be from a few yards to a few inches. Some RVs, vans and motor homes actually have personal computers in them that can be used for all typical computer purposes as well as automotive use.
Fuel systems - Controlling fuel and air mixtures falls into the duties of diagnostic controllers, however, there are other fuel considerations. Many vehicles now have economy cruise setting that actually turn off fuel to multiple engine cylinders.
Cabin environment - Environmental control of the temperature of the cabin is a frequent use of a microcontroller. Many vehicles offer this and optionally, control of separate zones of the cabin. Cabin comfort also includes entertainment.
Suspension - Many vehicle manufacturers now offer computer controlled ride and load sensing. Considerations among many others are how much sway is allowed on turns, how much road vibrations is controlled or dampened, how much the shock absorbers "pump up" to smooth out the road, how much extra resistance towing packages use to level vehicles pulling heavy loads.
Others - As time goes on, many other factors will be controlled directly or indirectly by computers. There are many in the experimental stages now, including complete driverless operation. Lighting, visibility, airflow dynamics, driver recognition, tracking, self protection, positioning, general operability and advanced environmental controls are nearing or in early release to the public. Some of the multiple computers act in a network, actually communicating with other computers in the vehicle. Some vehicles have a central communications computer that has a wireless interface with one or more outside world networks. If they could only make enough money to pay for themselves...
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