Integrator

integrator

(1) In electronics, a device that combines an input with a variable, such as time, and provides an analog output; for example, a watt-hour meter.

(2) See systems integrator.

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integrator [′int·ə‚grād·ər]

(electronics)

A computer device that approximates the mathematical process of integration.

integrating network

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Integrator 

a computing device for the determination of an integral, for example, of the form Z = ∫^x1y dx, where x and y are the input variables. The input variables may be mechanical displacement, pressure, electric current (voltage), the number of pulses, temperature, and the like. An integrator can be used as an independent computer for the solution of mathematical problems by integration methods, it can serve as a component of an automatic control system (the integrating network), it can be part of a computer, or it can be used for the simulation of a physical process. Thus, for example, hydraulic integrators are used for the study of transient processes in heat transfer, filtration, and diffusion. The variables investigated are represented by the levels of fluid in vessels connected through the so-called tubes of resistance. If the valves in the tubes are opened, then the initial levels of fluid are redistributed in accordance with the given conditions. Finding the values of the output variable leads in this case to the measurement of the fluid levels in the vessels. The basic element of electronic continuous-action (analog) integrators is a capacitor, the voltage across which is proportional to the integral of the current passing through the capacitor in the feedback circuit of a computer amplifier. Such integrators are usually included in analog computers.

Digital integrators are part of digital differential analyzers, as well as certain specialized computing devices such as interpolators. The integration of a function in digital integrators is replaced by the operation of summing a finite number of successive values of the function (its increments) given at discrete points, while the incoming and outgoing numerical information is represented in the form of electrical pulses, and the integration is accomplished by summing these pulses. Selecting a sufficiently small value for the pulses, one may in practice provide the necessary accuracy when replacing the integral by a sum; the accuracy of an analog integrator is limited.

REFERENCES

Fel’dbaum, A. A. Vychislitel’nye ustroistva v avtomaticheskikh sistemakh. Moscow, 1959.
Tsifrovye analogi dlia sistem avtomaticheskogo uprayleniia. Moscow-Leningrad, 1960.
Raymond, F. H. Avtomatika pererabotki informatsii. Moscow, 1961.(Translated from French.)

M. M. GEL’MAN