Analog computer

analogue computeranaloganalog computersanalog computinganalog computationanaloguemechanical calculatorscomputercomputerselectronic analog computer
An analog computer or analogue computer is a type of computer that uses the continuously changeable aspects of physical phenomena such as electrical, mechanical, or hydraulic quantities to model the problem being solved.wikipedia
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Slide rule

slide rulescircular slide ruleslide-rule
Slide rules and nomograms are the simplest, while naval gunfire control computers and large hybrid digital/analog computers were among the most complicated.
The slide rule, also known colloquially in the United States as a slipstick, is a mechanical analog computer.

Computer

computerscomputer systemdigital computer
An analog computer or analogue computer is a type of computer that uses the continuously changeable aspects of physical phenomena such as electrical, mechanical, or hydraulic quantities to model the problem being solved.
The Antikythera mechanism is believed to be the earliest mechanical analog "computer", according to Derek J. de Solla Price.

Antikythera mechanism

Antikythera Mechanism Research ProjectOrrery
The Antikythera mechanism was an orrery and is believed to be an early mechanical analog computer, according to Derek J. de Solla Price.
The Antikythera mechanism is an ancient Greek analogue computer used to predict astronomical positions and eclipses for calendar and astrological purposes decades in advance.

Hybrid computer

Hybridhybrid analog computershybrid computing
More complex applications, such as aircraft flight simulators and synthetic aperture radar, remained the domain of analog computing (and hybrid computing) well into the 1980s, since digital computers were insufficient for the task.
Hybrid computers are computers that exhibit features of analog computers and digital computers.

Antikythera wreck

Antikythera shipwreckAntikytheraAntikythera ship
It was discovered in 1901 in the Antikythera wreck off the Greek island of Antikythera, between Kythera and Crete, and has been dated to circa 100 BC during the Hellenistic period of Greece.
The wreck yielded numerous statues, coins, and other artifacts dating back to the fourth century BC, as well as the severely corroded remnants of a device many regard as the world's oldest known analog computer, the Antikythera mechanism.

Flight computer

flight computing device
Analog computers were widely used in scientific and industrial applications even after the advent of digital computers, because at the time they were typically much faster, but they started to become obsolete as early as the 1950s and 1960s, although remained in use in some specific applications, such as aircraft flight simulators, the flight computer in aircraft, and for teaching control systems in universities.
A flight computer is a form of circular slide rule used in aviation and one of a very few analog computers in widespread use in the 21st century.

Differential analyser

differential analyzerBush differential analyzerdifferential analysis
The differential analyser, a mechanical analog computer designed to solve differential equations by integration, used wheel-and-disc mechanisms to perform the integration.
The differential analyser is a mechanical analogue computer designed to solve differential equations by integration, using wheel-and-disc mechanisms to perform the integration.

Tide-predicting machine

Tide Predicting Machinetide predictorpredict tides
The tide-predicting machine invented by Sir William Thomson in 1872 was of great utility to navigation in shallow waters.
A tide-predicting machine was a special-purpose mechanical analog computer of the late 19th and early 20th centuries, constructed and set up to predict the ebb and flow of sea tides and the irregular variations in their heights – which change in mixtures of rhythms, that never (in the aggregate) repeat themselves exactly.

Vannevar Bush

Bush, VannevarBushV. Bush
Starting in the 1920s, Vannevar Bush and others developed mechanical differential analyzers.
He is known particularly for his engineering work on analog computers, and for the memex.

Astronomical clock

astronomicalastronomical clock towerastronomical clock towers
The castle clock, a hydropowered mechanical astronomical clock invented by Al-Jazari in 1206, was the first programmable analog computer.
The most sophisticated water-powered astronomical clock was Al-Jazari's castle clock, considered to be an early example of a programmable analog computer, in 1206.

Network analyzer (AC power)

A-C network calculatorAC network analyzers1949
Starting in 1929, AC network analyzers were constructed to solve calculation problems related to electrical power systems that were too large to solve with numerical methods at the time.
These special-purpose analog computers were an outgrowth of the DC calculating boards used in the very earliest power system analysis.

Arthur Pollen

Argo ClockArgo systemArgo
By 1912 Arthur Pollen had developed an electrically driven mechanical analog computer for fire-control systems, based on the differential analyser.
His most important technical innovation was one of the world’s first electrically-powered analogue computers, patented as the Argo Clock: a differential analyser which enabled big guns to engage with long-range targets when both ships were moving at speed in different directions.

Machine

machinerymechanicalmachines
Abū Rayhān al-Bīrūnī invented the first mechanical geared lunisolar calendar astrolabe, an early fixed-wired knowledge processing machine with a gear train and gear-wheels, circa 1000 AD.
The castle clock, a hydropowered mechanical astronomical clock invented by Al-Jazari, was the first programmable analog computer.

FERMIAC

Monte Carlo trolley
The FERMIAC was an analog computer invented by physicist Enrico Fermi in 1947 to aid in his studies of neutron transport.
The Monte Carlo trolley, or FERMIAC, was an analog computer invented by physicist Enrico Fermi to aid in his studies of neutron transport.

Deltar

Around 1950 this idea was developed into the Deltar, an analogue computer supporting the closure of estuaries in the southwest of the Netherlands (the Delta Works).
The Deltar (Delta Getij Analogon Rekenmachine, Dutch for Delta Tide Analog Calculator) was an analog computer, used for the design and implementation of the Delta Works from 1960 until 1984.

Fire-control system

fire controlfire control systemfire-control director
By 1912 Arthur Pollen had developed an electrically driven mechanical analog computer for fire-control systems, based on the differential analyser.
Then increasingly sophisticated mechanical calculators were employed for proper gun laying, typically with various spotters and distance measures being sent to a central plotting station deep within the ship.

Synthetic-aperture radar

synthetic aperture radarSARsynthetic aperture
More complex applications, such as aircraft flight simulators and synthetic aperture radar, remained the domain of analog computing (and hybrid computing) well into the 1980s, since digital computers were insufficient for the task.
The processor was to be, in effect, an optical analog computer performing large-scale scalar arithmetic calculations in many channels (with many light "rays") at once.

Operational amplifier

op-ampop ampoperational amplifiers
The electrical equivalent can be constructed with a few operational amplifiers (op amps) and some passive linear components; all measurements can be taken directly with an oscilloscope.
Operational amplifiers had their origins in analog computers, where they were used to perform mathematical operations in many linear, non-linear, and frequency-dependent circuits.

V-2 rocket

V-2V2V2 rocket
In 1942 Helmut Hölzer built a fully electronic analog computer at Peenemünde Army Research Center as an embedded control system (mixing device) to calculate V-2 rocket trajectories from the accelerations and orientations (measured by gyroscopes) and to stabilize and guide the missile.
Some later V-2s used "guide beams", radio signals transmitted from the ground, to keep the missile on course, but the first models used a simple analog computer that adjusted the azimuth for the rocket, and the flying distance was controlled by the timing of the engine cut-off, "Brennschluss", ground controlled by a Doppler system or by different types of on-board integrating accelerometers.

Dumaresq

The Dumaresq was a mechanical calculating device invented around 1902 by Lieutenant John Dumaresq of the Royal Navy.
It is an analogue computer that relates vital variables of the fire control problem to the movement of one's own ship and that of a target ship.

Clock tower

clocktowertower clockcastle clock
The castle clock, a hydropowered mechanical astronomical clock invented by Al-Jazari in 1206, was the first programmable analog computer.
Al-Jazari's castle clock is considered to be the earliest programmable analog computer.

Derek J. de Solla Price

Derek de Solla PricePrice's lawPrice
The Antikythera mechanism was an orrery and is believed to be an early mechanical analog computer, according to Derek J. de Solla Price.

Helmut Hölzer

Helmut HoelzerHelmut Holzer
In 1942 Helmut Hölzer built a fully electronic analog computer at Peenemünde Army Research Center as an embedded control system (mixing device) to calculate V-2 rocket trajectories from the accelerations and orientations (measured by gyroscopes) and to stabilize and guide the missile.
Then at the beginning of 1942, Hoelzer built an analog computer to calculate and simulate V-2 rocket trajectories Hoelzer's team also developed the Messina telemetry system.

Bart N. Locanthi

Bart Locanthi
Computer Engineering Associates was spun out of Caltech in 1950 to provide commercial services using the "Direct Analogy Electric Analog Computer" ("the largest and most impressive general-purpose analyzer facility for the solution of field problems") developed there by Gilbert D. McCann, Charles H. Wilts, and Bart Locanthi.
From 1947–1960, he mostly contributed to analog computers.

Ismail al-Jazari

Al-Jazarial-Jazari, Ismailal-Jazarī
The castle clock, a hydropowered mechanical astronomical clock invented by Al-Jazari in 1206, was the first programmable analog computer.
Al-Jazari's castle clock is considered to be the earliest programmable analog computer.