自动化专业外文翻译--自动控制的发展历史3.pdf

HISTORY OF A UTOM ATIC CONTR OL Feedback control i s the basi c mechani sm by w hi ch sy stems, w hether mechani cal , el ectri cal , or bi ol ogi cal , maintain thei r equilibrium or homeostasi s. In the hi gher li fe forms, the condi ti ons under w hi ch li fe can continue are qui te narrow . A change i n body temperature of hal f a degree i s generally a si gn of illness. The homeostasi s of the body i s mai ntained through the use of feedback control [Wi ener 194 8] . A primary contributi on of CR Darw in duri ng the l ast century w as the theory that feedback ov er l ong time peri ods i s responsibl e for the ev oluti on of speci es. In 193 1 V. Vol terra expl ained the bal ance betw een tw o popul ati ons of fi sh in a cl osed pond using the theory of feedback . The use of feedback to control a sy stem has a fascinating hi story .The first appli cati ons of feedback control appeared in the dev el opment of fl oat regul ator mechani sms in Greece in the peri od 300 to1B .C . The w ater cl ock of ktesibi os used a fl oat regul ator. A n oil l amp devi sed by Phil on in approximately 2 50 B .C .U sed a fl oat regul ar in an oil l amp for maintaining a constant l ev el s of fuel oil .Heron of A l ex andri a, w ho liv ed in the fi rst century A .D, publi shed a book enti tl ed Pneumati ca, w hi ch outlined sev eral forms of w ater-l ev el mechani sms usi ng fl oating regul ators The first feedback sy stem to be inv ented in modern Europe w as the temperature regul ator of Corneli s Drebb(1572-1633) of Holl and Denni s Papin inv ented the fi rst pressure regul ator for steam boil ers In 1681.Papin ’s pressure regul ator w as a