【正文】 一般來說，一個反饋控制系統(tǒng)配置不得限制該feedback。這是一個閉環(huán)控制的典型例子。一個人可以被認為是一個控制系統(tǒng)有許多輸入和輸出，開展高度復雜的操作能力。閉環(huán)控制系統(tǒng)閉環(huán)控制缺少更準確和更適應由輸出反饋提高系統(tǒng)的輸入。這也指出了一個開環(huán)控制系統(tǒng)的性能重要的缺餡，該系統(tǒng)不能夠適應變化的環(huán)境或外部干擾。它通常意味著該系統(tǒng)通常是能夠適應不同的作業(yè)條件，并能有令人滿意的回應。此應用程序優(yōu)化的周邊裝置，與高性能的DSP核心，可提供了高精確度和高效率的全變速控制的所有汽車類型的先進控制技術(shù)。該240C使用亞微米CMOS制造技術(shù)，實現(xiàn)了日志的功耗等級。幾乎所有的指令執(zhí)行時間為50 ns。這兩個數(shù)字和混合信號外設庫包括：定時器串行通信接口（SCI的，SPI）模擬到數(shù)字轉(zhuǎn)換器（ADC）事件管理器系統(tǒng)保護，如低電壓和看門狗定時器該DSP控制器外設庫是不斷增長和變化的，以適應未來的嵌入式控制市場。它用于存儲中間結(jié)果的32位寄存器的16位字，并有兩個硬件可用號碼提供給獨立的CPU。高速中央處理單元（CPU）可處理的數(shù)字化設計，事實上，并不是與查表結(jié)果近似的算法。通過整合到一個單一芯片內(nèi)存和外設，TMS320系列設備降低了系統(tǒng)成本和節(jié)省電路板空間。F/C240是C2000DSP平臺，并控制應用而優(yōu)化。數(shù)字至模擬轉(zhuǎn)換MPEG音頻解碼，數(shù)字壓縮的數(shù)據(jù)反饋到執(zhí)行的DSP解碼，解碼后的樣本，將轉(zhuǎn)換成模擬域回來，與由此產(chǎn)生的信號放大器或類似的音頻設備。浮點DSP的表現(xiàn)更像是共同的通用CPU的寄存器文件。DSP的或多或少取決于兩類下降的基礎架構(gòu)的定點和浮點。大的廠家很多，像德州儀器，摩托羅拉，都提供專門的DSP像馬達控制或調(diào)制解調(diào)器這些領域的，和一般的高性能DSP處理，可以執(zhí)行廣泛的任務范圍。在許多情況下的模擬信號會用各種方法處理問題，在很多方面像濾波和頻譜分析，設計模擬硬件來執(zhí)行這些職能是可能的，但已變得越來越少，由于更高的性能需求，靈活性的需求，以及需要削減減少開發(fā)/測試的時間的需求。這允許程序自動輸入和存儲在每個機床上。這個問題引導了計算機數(shù)控的發(fā)展。在直接數(shù)字控制下，精密機床的束縛，通過數(shù)據(jù)傳輸鏈路，連接在主機和機器工具，通過數(shù)據(jù)傳輸連接需要。即使是在一個最微小的調(diào)整方案，也需要中斷才能加工，并制作出新的磁帶。如果生產(chǎn)預先制定的100份，還需要運行100個紙帶獨立運行的時間?？傊?，所有一切都代表數(shù)控控制的大步發(fā)展。這個問題導致了1959年自動編程工具（APT）語言的發(fā)展，使用類似數(shù)控英文語句來定義幾何零件，描述刀具配置，并制定所需的方案。在最初階段，數(shù)控機床能夠使直接有效地削減人力。數(shù)控機床也比他們更早的機器更為的靈活。2。數(shù)控開發(fā)，克服了人工操作的局限性，并且已經(jīng)完成。用手動控制，產(chǎn)品質(zhì)量直接相關(guān)，并僅限于操作者的技能。 but id the doors or windows are opened or closed intermittently during the operating period, the final temperature inside the house will not be accurately regulated by the openloop control.An electric washing machine is another typical example of an openloop system , because the amount of wash time is entirely determined by the judgment and estimation of the human operator . A true automatic electric washing machine should have the means of checking the cleanliness of the clothes continuously and turn itsedt off when the desired degised of cleanliness is reached.ClosedLoop Control SystemsWhat is missing in the openloop control system for more accurate and more adaptable control is a link or feedback from the output to the input of the system . In order to obtain more accurate bontrol, the controlled signal c(t) must be fed back and pared with the reference input , and an actuating signal proportional to the difference of the output and the input must be sent through the system to correct the error. A system with one or more feedback pat(s like that just described is called a closedloop system. human being are probably the most plex and sophisticated feedback control system in existence. A human being may be considered to be a control system with many inputs and outputs, capable of carrying out highly plex operations.To illustrate the human being as a feedback control system , let us consider that the objective is to reach for an object on aperform the task. The eyes serve as a sensing device which feeds back continuously the position of the hand . The distance between the hand and the object is the error , which is eventually brought to zero as the hand reacher the object. This is a typical example of closedloop control. However , if one is told to reach for the object and then is blindolded, one can only reach toward the object by estimating its exact position. It isAs anther illustrative example of a closedloop control system, shows the block diagram of the rudder control system ofThe basic alements and the bloca diagram of a closedloop control system are shown in fig. In general , the configuration of a feedback control system may not be constrained to that of fig amp。Numerical Control One of the most fundamental concepts in the area of advanced manufacturing technologies is numerical control (NC).Prior to the advent of NC, all machine tools were manual operated and controlled. Among the many limitations associated with manual control machine tools, perhaps none is more prominent than the limitation of operator skills. With manual control, the quality of the product is directly related to and limited to the skills of the operator . Numerical control represents the first major step away from human control of machine tools.Numerical control means the control of machine tools and other manufacturing systems though the use of prerecorded, written symbolic instructions. Rather than operating a machine tool, an NC technician writes a program that issues operational instructions to the machine tool, For a machine tool to be numerically controlled , it must be interfaced with a device for accepting and decoding the p2ogrammed instructions, known as a reader.Numerical control was developed to overe the limitation of h