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Analog computer

Analog computer definition

An analog computer is a type of computer that is used to process analog data. It needs a physical input, using electrical, mechanical, or hydraulic quantities to enter the problem that needs to be solved. Analog computers were widely used in the 20th century for scientific and engineering calculations but have been largely replaced by digital computers for most purposes. For example, to perform a multiplication operation, two voltage signals representing the input values are applied to a circuit that generates an output voltage proportional to their product. To perform integration or differentiation, a circuit is used that generates an output voltage proportional to the integral or derivative of the input voltage.

Analog computer history

The first widely recognized analog computers were developed in the early 20th century. One of the earliest examples was the differential analyzer, invented by Vannevar Bush in the 1920s at MIT. It used mechanical gears and shafts to solve differential equations.

Other early analog computers included the electro-mechanical integrators developed by British engineer Douglas Hartree and the hydraulic analog computers developed by French engineer Georges R. de Sarrio. These early machines laid the foundation for the development of modern analog computers and the use of analog computing techniques.