【正文】 response due to two different inputs, then the response due to the bined input is equal to the sum of the individual response due to the bined input is equal to the individual responses. Another benefit is that operational mathematics can be used in the analysis of linear systems. The operational method allows us to transform ordinary differential equations which are much simpler to handle. Traditionally, control system were represented by higherorder linear differential equations and the techniques of operational mathematics were employed to study these equations. Such an approach is referred to as the classical method and is particularly useful for analyzing systems characterized by a single input and a single output. As systems began to bee more plex , it became increasingly necessary to use a digital Computer . The work on a puter can be advantageously carried out if the system under consideration is represented by a set of firstorder differential equations and the analysis is carried out via matrix theory. 8 This is in essence what is referred to as the state space or state variable approach . This method , although applicable to single inputoutput systems , finds important applications in the multivariable system . Another very attractive benefit is that it enables the control system engineer to study variables inside a system. Regardless of the approach used in the design and analysis of a control system , we must at least following steps: (1) Postulate a control system and the system specifications to be satisfied. (2) Generate a functional block diagram and obtain a mathematical representation of the system . (3) Analyze the system using any of the analytical or graphical methods applicable to the problem. (4) Check the performance (speed , accuracy, stability, or other eriterion) to see if the problem. (5) Finally, optimize the system parameters so that (1) is satisfied. 控制系統(tǒng)的介紹 1. 歷史回顧 早在人類歷史文明出現(xiàn)之初，人們就產(chǎn)生了控制自然力的愿望。其結(jié)果是出現(xiàn)了許多新的制造方法，如計(jì)算機(jī)輔助設(shè)計(jì)和計(jì)算機(jī)輔助制造，而且計(jì)算機(jī)控制的機(jī)器，機(jī)械手和機(jī)器人帶來(lái)了生產(chǎn)率空前提高。這些噴射出的火焰為衛(wèi)星的動(dòng)態(tài)提供必要的糾正信號(hào)，從而使衛(wèi)星處于被控制之中。例如，某一建筑物內(nèi)使用的空調(diào)只要維持 +/— 0。這種方法雖然也能用于單輸入單輸出系統(tǒng)，更重要的是用于多變量系統(tǒng)。如 果被研究的系統(tǒng)用一組一階微分方程組來(lái)描述，并用矩陣?yán)碚搧?lái)分析，則在計(jì)算機(jī)上就很容易完成這一任務(wù)。所謂穩(wěn)定性是指輸出始終保持在某一合理的范圍內(nèi)。我們 10 希望衛(wèi)星相對(duì)某個(gè)慣性坐標(biāo)系具有指定的姿態(tài)角，實(shí)際的狀態(tài)角由衛(wèi)星上的一個(gè)姿態(tài)角傳感器測(cè)量。人造地球衛(wèi)星時(shí)代的后期，在系統(tǒng)最優(yōu)化和自適應(yīng)系統(tǒng)方面也做了不少努力。 4 Introduction to Control System 1. 1 HISTORICAL PERSPECTIVE The desire to control the forces of nature has been with man since early civilizations. Although many examples of co