Now in almost every home there is a computer for work, study, entertainment or all at once. A modern PC has appeared thanks to an electronic computer, so computers often mean an old version of a computer. But few people know about the existence of AVM.
The concept
AVM is an analog computer, which is a kind of prototype of a computer. It works with numerical data that is developed thanks to analog physical parameters. These include indicators of speed, length, strength, pressure, etc.
In addition to the operation algorithms, an analog computer differs from a computer in that it lacks a control program. That is, there are no special teams that would help him cope with the tasks. In this case, the task is set in front of the machine by the internal device and the settings that are set.
The beginning of the story
Before the very first computer in the world appeared, the device had to go a difficult way. It is believed that the analog device, which gave rise to such devices, was first developed in 100 BC. The antikythera mechanism was found after 2 thousand years. The device got its name due to the place where it was found - the island of Antikythera.
Astrolabe is also considered quite popular. This invention was known in scientific circles among astrologers and astronomers even before our era, helped to determine the location of stars in the sky and to understand the duration of the day.
Active development
Since the 17th century, the active development of analog devices begins. So a slide rule appears, which, although you cannot call a computer, can still be attributed to an analog computing device.
Literally 20 years later, "Pascalina" appears, and then Morland's car. In the XIX century, a planimeter was invented, which helped at that time to find the area of the curve. Later - an integrator, which does not look like an analog computer, is still a device that easily calculates the integrals.
In the XX century, Russian scientists began to engage in active development. For example, Alexey Krylov invented a device that helped solve differential equations. Later, this invention was used to design ships.
After 8 years, equipment was created on the basis of what Krylov came up with, but who are engaged in the integration of differential equations. Soon, a mechanical integrating invention and an electrodynamic counting and analytical device appeared.
The mechanical AVM became famous thanks to Konrad Zuse, who created the Z1. With the advent of the amplifier, AVMs without moving parts began to work on direct current.
The USSR was also engaged in development. Therefore, already in 1949, DCM AVMs were released. The first neurocomputer perceptron appears immediately. All these inventions led to the fact that in the 60s of the XX century, analog computers became the main assistant to scientists around the world.
Device operation
It is not easy to determine exactly when the very first computer in the world appeared. In this case, most often remember IBM, developed at Harvard in 1941. But there is no similar information on AVM in this regard. But now this is not so important. The principle of action is much more interesting.
An analog computer is engaged in calculations, all digital data may vary depending on the results. The latter are represented by graphs, which are usually displayed on paper or display. Also, the result can be obtained in the form of an electrical signal. It simultaneously controls the calculation process and the operation of the equipment.
Features
An analog computer can easily cope with the automatic regulation of various production processes. This is due to the fact that the AVM quickly responds to any data changes. Therefore, such a device will be beneficial during scientific research, when the input values may vary during the process.
AVM can be useful in science, which does not require expensive electrical appliances. It is enough for devices to be able to imitate the studied processes. Sometimes such a machine is needed in order to solve problems that do not require the same accuracy of calculations as in the case of computer tasks.
Electronic analog computers can easily cope with differential equations, integrations, etc. To solve such problems, it is enough to use special circuits and nodes. In the case of the AVM, such commands are not required, so the operation of this device is somewhat simpler.
Analog block
The description of an analog computer must contain its elements. The operational unit includes such details that are occupied by one of the tasks. All of them can be combined into a system to work on one operation according to a specific model.
AVM blocks can be divided into several groups:
The linear group includes parts that deal with mathematical operations. A nonlinear group includes blocks that work with a nonlinear dependence of a function on different variables. A logical group contains elements of continuous, discrete logic.
There are several types of analog computers, so their composition may slightly differ from the available options.
Basic elements
In addition to the above blocks, there are basic elements that have their own specific parameters. There is a capacitive charger, which is based on capacitor properties and can store voltage.
The voltage divider also applies to the memory. In this case, the rotation angles of the rheostats affect the operation. They depend on the values to be remembered. The main blocks include a memory pair, which is often represented by an operational amplifier. One can function in tracking the input signal, the other in storage.
Characteristic
Like any device, an analog computer has features. But the most basic is quality factor. This is a generalized parameter of a machine that has a specific formula. Some values depend on the level of interference and are also affected by errors and accuracy.
Varieties
As mentioned earlier, AVMs can be of various types. But in general, each option can be sent to one of two groups:
- specialized - for narrow special tasks;
- universal - for any task option.
Further, all analog computers can be divided into dependent on the type of working fluid, according to design features and the type of operation.
Type of working fluid
The capabilities of an analog computer determined its type. But not only the functioning affects the differentiation of devices. It also depends on the type of working fluid. So, there are:
- mechanical;
- pneumatic;
- hydraulic;
- electric;
- combined;
- electromechanical.
The mechanical type includes such devices that have mechanical displacements. Due to the peculiarities of this variant of the machine, it is necessary to scale the variables, as well as to conduct a force calculation of the structure and dead moves.
This type has its advantages and disadvantages. The machine is reliable and copes with various mathematical problems. However, it has a high cost, a difficult development mechanism and large size.
Pneumatic view works with indicators of air pressure. To get the results you need to get a built network. As part of this machine, you can often see chokes, tanks and membranes.
This type of AVM practically does not have any errors. Now it can often be found in industry, which requires increased vibration resistance and work at temperature extremes.
The hydraulic type works with differential equations that are related to the flow of water. Previously, these machines could be found in many companies, until the 80s of the XX century. Now there are only two hydraulic AVMs that are in the museum.
By analogy, one can guess that electrical devices take DC voltage for the indicators. They are popular for their reliable properties, speed, convenient regulation and accurate final data.
The electromechanical type has mechanical and electrical variables. This type of machine is characterized by rotating transformers and tachogenerators. The device has sliding contacts, so it is less reliable than the previous options.
Design features
This includes:
An AVM of a matrix type has separate elements that are combined strictly into groups according to certain criteria. This option is suitable for creating differential equations. But the execution of processes needs to be configured in a certain way.
Groups that have certain characteristics work each with its own task. For proper research, you need to use scale. This type has low efficiency.
The structural type of the AVM is represented by devices having computing units. In this case, they are not strictly combined, but due to the tasks that are needed to parse the operation. Designed machine for mathematical modeling.
Functioning
This group includes devices:
The fast type is configured so that the steps of solving processes are repeated automatically. This is done thanks to the switching system. The repetition rate depends on the characteristics of the parts. To work at this speed requires a complex design. The advantage of such a machine is the ability to observe the results of experiments.
The slow type has a single action. The solution of ordinary processes in this case can take from several seconds to several minutes. The result of research can be seen only after the end of all cycles.
Iterative AVM uses an iterative method to solve. A machine of this type allows you to control the progress of the experiment at certain times.
Use of machines
Electronic analog computers have been known for a long time, so they went through a certain stage of improvement. These devices are based on setting the physical parameters of the elements. Usually this process occurs due to the inclusion and exclusion of some blocks from the system.
Before the AVM reached its peak, similar devices were used in aviation and rocket technology. Machines in this case helped to quickly process data and generate signals for control. So autopilots and more sophisticated flight control systems became known.
You can also find an analog system in the car. Here it is the transmission. When the torque changes, the fluid changes the pressure in the hydraulic actuator. Thus, a certain transmission coefficient occurs.
As mentioned earlier, often AVMs are classified as highly specialized devices, so they are used for special tasks. The cam mechanical analog device was previously known. It was used in steam locomotive building.
Mechanical computers have become popular in space. They helped to collect data thanks to surface indicators. Until 2002, the Globus computer was known, which coped with similar tasks.
There are analog devices in military equipment. They are responsible for managing artillery fire, calculating various indicators during battles, etc. In this case, fast machines are used that can easily cope with interference.
Examples
There are a lot of examples of analog computers during their existence. For example, in 1962, the Iterator AVM was created. It helped solve a special kind of problems associated with linear equations. This device functions thanks to the special way scientists owe it to Newton. Iterator also copes with linear algebraic equations.
Also, the world knows a whole series of MN devices. The name is an abbreviation - "non-linear model." Initially, the device was supposed to work with Cauchy's tasks. The most striking representative of the line is the "MN-18." This is a medium power device that can solve complex dynamic systems. He does this using mathematical modeling.
Also worth mentioning is the Monte Carlo Cart. This computer came about thanks to Enrico Fermi. It was designed to study the motion of neutrons. To obtain the results, the Monte Carlo method was taken as a basis.
ZAM is another family of analog machines that were created in Warsaw. Their production began in the 60s of the XX century. Each device worked on the basis of a binary number system.
Note
It is generally accepted that the human brain is the most popular “analog device”. Scientists consider it a powerful and efficient device that has ever existed. Of course, one can argue with this statement, since the operation of pulses is carried out due to discrete signals. But the data in the nervous system does not have a digital look.
Digital and analog computers combined to form neurocomputers. These are hybrid devices, which, although classified as analog, are built on digital computers. These machines work similarly to brain cells.