自动化专业外文文献

1、Development of Sensor New TechnologySensor is one kind component which can transform the physical quantity, chemistry qua ntity and the biomass in to electrical sig nal. The output sig nal has the different forms like the voltage, the electric current, the frequency, the pulse and so on, which can s

2、atisfy the signal transmission, processing, recordi ng, and dem on strati on and con trol dema nds. So it is the automatic detect ion system and in the automatic con trol in dustry f automatic Tech no logy is used wider, the n sen sor is more importa nt.Several key words of the sensor :1 Sen sor Ele

3、me ntsAlthough there are exception ,most sensor consist of a sensing element and a conversion or control element. For example, diaphragms,bellows,strain tubes and rin gs, bourd on tubes, and can tilevers are sensing eleme nts which resp ond to cha nges in pressure or force and con vert these physica

4、l qua ntities into a displaceme nt. This displaceme nt may the n be used to cha nge an electrical parameter such as voltage, resista nee, capacita nee, or in ducta nee. Such comb in ati on of mecha ni cal and electrical eleme nts form electromecha ni cal tran sduc ing devices or sen sor. Similar com

5、b in ati on can be made for other en ergy in put such as thermal. Photo, magn etic and chemical,giving thermoelectric, photoelectric,electromaanetic, and electrochemical sen sor respectively.2 Sen sor Sen sitivityThe relati on ship betwee n the measured and the sen sor output sig nal is usually obta

6、ined by calibration tests and is referred to as the sensor sensitivity K1 = output-sig nal in creme nt / measuredi ncreme nt .In practice, the sen sor sen sitivity is usually known, and, by measuri ng the output sig nal, the in put qua ntity is determ ined from in put= output-sig nal in creme nt / K

7、1.3 Characteristics of an Ideal Sen sorThe high sen sor should exhibit the follow ing characteristics.(a) high fidelity-the sensor output waveform shape be a faithful reproduction of the measured; there should be mi nimum distortio n.(b) There should be minimum interferenee with the quantity being m

8、easured; the prese nee of the sen sor should not alter the measured in any way.(c) Size. The sen sor must be capable of being placed exactly where it is n eeded.(d) There should be a lin ear relatio nship betwee n the measured and the sen sor sig nal.(e) The sen sor should have mi nimum sen sitivity

9、 to exter nal effects, pressure sen sor,for example,are ofte n subjected to exter nal effects such vibrati on and temperature.(f) The n atural freque ncy of the sen sor should be well separated from the freque ncy and harm onics of the measura nd.Sen sors can be divided into the follow ing categorie

10、s1 Electrical Sen sorElectrical sensor exhibit many of the ideal characteristics. In addition they offer high sensitivity as well as promoting the possible of remote indication or mesdureme nt.Electrical sen sor can be divided into two dist inct groups:(a) variable-c on trol-parameter types,which in

11、 clude:(i) resista nee(ii) capacita nee(iii) i nducta nee(iv) mutual-in ducta nee typesThese sensor all rely on external excitation voltage for their operation.(b) self-ge nerat ing types,which in clude(i) electromag netic(ii) thermoelectric(iii) photoemissive(iv) piezo-electric typesThese all thems

12、elves produce an output voltage in resp onse to the measura nd input and their effects are reversible. For example, a piezo-electric sensor normally produces an output voltage in response to the deformation of a crystalline material; however, if an alternating voltage is applied across the material,

13、 the sensor exhibits the reversible effect by deforming or vibrating at the frequency of the alternating voltage.2 Resista nee Sen sorResista nee sen sor may be divided into two groups, as follows:(i) Those which experie nee a large resista nee cha nge, measured by using potential-divider methods. P

14、otentiometers are in this group.(ii) Those which experie nee a small resista nee cha nge, measured by bridge-circuit methods. Examples of this group in clude stra in gauges and resista nee thermometers.3 Capacitive Sen sorThe capacita nee can thus made to vary by cha nging either the relative permit

15、tivity, the effective area, or the distance separating the plates. The characteristic curves indicate that variations of area and relative permittivity give a linear relationship only over a small range of spacings. Thus the sensitivity is high for small values of d. Un like the pote nti onm eter, t

16、he variable-dista nce capacitive sen sor has an infin ite resoluti on making it most suitable for measuri ng small in creme nts of displaceme nt or qua ntities which may be cha nged to produce a displaceme nt.4 In ductive Sen sorThe inductance can thus be made to vary by changing the reluctance of t

17、he inductive circuit.Measuri ng tech niq ues used with capacitive and in ductive sen sor:(a) A.C. excited bridges using differe ntial capacitors in ductors.(b) A.C. pote ntiometer circuits for dyn amic measureme nts.(c) D.C. circuits to give a voltage proporti onal to velocity for a capacitor.(d) Fr

18、eque ncy-modulatio n methods, where the cha nge of C or L varies the freque ncy of an oscillation circuit.Importa nt features of capacitive and in ductive sen sor are as follows:(i) resolution infinite(ii) accuracy 0.1% of full scale is quoted-6-3(iii) displacement ranges 25*10 m to 10 m(iv) rise ti

19、me less tha n 50us possibleTypical measura nds are displaceme nt, pressure, vibrati on, sound, and liquid level.5 Lin ear Variable-differe ntial Ttran sformer6 Piezo-electric Sen sor7 Electromag netic Sen sor8 Thermoelectric Sen sor9 Photoelectric Cells10 Mecha ni cal Sen sor and Sensing Eleme ntsIn

20、 information age, the information industry includes information gathering, tran smissi on, process three parts, n amely sen sor tech no logy, com muni cati on, computer tech no logy. Because of ultra large scale in tegrated circuitapiddevelopme nt after hav ing bee n developed Moder n computer tech

21、no logy and com muni cati on, not only requests sen sor precisi onreliability, speed of response and gain information content request more and more high but also requests its cost to be inexpensive. The obvious traditional sensor is eliminated gradually because of the function, the characteristic, t

22、he volume, the cost and so on. As world develop many countries are speeding up to the sen sor new tech no logy research and the developme nt, and all has obta ined the eno rmous breakthrough. Now the sen sor new tech no logy developme nt mai nly has followi ng several aspects:Usi ng the physical phe

23、 nomenon, the chemical react ion, the biological effect as the sensor principle therefore the researches which discovered the new phe nomenon and the new effect are the sen sor tech no logical improvi ng ways .it is important studies to developed new sensor the foundation. Japa nese Sharp Corporati

24、on uses the superc on ductivity tech no logy to develop successfully the high temperature superconductivity magnetic sensor and get the sen sor tech no logy sig nifica nt breakthrough. Its sen sitivity is so high and only inferior in the superconductivity quantum interferenee component. Its manufact

25、ure craft is far simpler than the superconductivityquantumin terfere nee comp onent. May use in magn etism image formati on tech no logy. So it has the widespread promoted value.Using the immune body and the an tige n meets one ano ther compo und whe n the electrode surface. It can cause the electro

26、de potential change and use this phe nomenon to be possible to gen erate the immun ity sen sor. The immu nity sensor makes with this kind of immune body may to some organism in whether has this kind of ant original work inspection. Like may inspect somebody with the hepatitis virus immune body wheth

27、er con tracts the hepatitis, plays to is fast, the accurate role. The US UC sixth branch has developed this kind of sen sor.The sen sor material is the importa nt foun datio n for sen sor tech no logy, because the materials scienee is progressive and the people may make each kind of new sen sor For

28、example making the temperature sen sor with the high polymer thin film; The optical fiber can make the pressure, the current capacity, the temperature, the displacement and so on the many kinds of sen sors; Mak ing the pressure tran smitter with the ceramics. The high polymer can become the proporti

29、 on adsorptio n and the release hydroge n along with the en vir onment relative humidity size. The high polymer electricity lies betwee n the constant to be small, the hydrogen can enhance the polymer the coefficient of dialectical loss. Maki ng the capacitor the high polymer dielectric medium, dete

30、rm ines the electric capacity cape city the cha nge, the n obta ins the relative humidity. Making the plasma using this principle to gather the legitimate polystyre ne film temperature sen sor below, it has the characteristic.Measured the wet scope is wide; The temperature range is wide, may reach -

31、400 C +1,500 C ; The speed of response is quick, is smaller than 1S; The size is small, may use in the small space measuring wet; The temperature coefficie nt is small.The ceramic electric capacity type pressure tran smitter is one kind does not have the intermediary fluid the dry type pressure tran

32、smitter. Uses the adva need ceramic tech no logy, the heavy film electr onic tech no logy, its technical performanee is stable, the year drifting quantity is smaller than 0.1%F.S, warm floats is smaller than ).15%/10K, anti- overloads strongly, may reach the measuri ng range several hun dred times.

33、The survey scope may from 0 to 60mpa.German E+H Corporation and the American Kahlo Corporati on product is at the lead ing positi on.The optical fiber application is send the material significantbreakthrough,its uses in most early the optical com muni cati on tech niq ues. In the optical com muni ca

34、ti on use discovered works as en vir onmen tal con diti on cha nge and so on the temperature, pres-sure, electric field, magnetic field, causes the fiber optic tran smissi on light wave inten sity, the phase, the freque ncy, cha nge and so on the polarization condition, the survey lightwave quantity

35、 change, mayknow causes these light wave physical quantity the and so on quantitative change temperature, pressure ,electric field, magnetic field size, uses these prin ciples to be possible to develop the optical fiber sen sor. The optical fiber sen sor and the traditi onal sen sor compare has many

36、 characteristics: Sen sitivity high, the structure simple, the volume small, anti-corrosive,the electricinsulation good, the path of rays may be curving, be advantageous for the realization telemeter and so on. Optical fiber sensor Japan is in the advaneed level. Like Idec Izumi Corporation and Sun

37、x Corporation. The optical fiber send receiver and the in tegrated path of rays tech no logy unify, accelerates the optical fiber sen sor tech no logy developme nt. Will in tegrate the path of ray s comp onent to replace the orig inal optics part and the passive light comp onent; enable the optical

38、fiber sensor to have the high band width, the low signal processing voltage, the reliability high, the cost will be low.In semic on ductor tech no logy process ing method oxyge nati on, the photo etc hang, the proliferation, the deposition, the plane electron craft, various guides corrosion and stea

39、ms plates, the sputtering thin film and so on, these have all introduced to the sensor manufacture. Thus has produced each kind of new sen sor, like makes the silic on micro sen sor using the semic on ductor tech no logy, makes the fast resp onse using the thin film craft the gas to be sensitive, th

40、e wet sensitive sensor, the use sputtering thin film craft system pressure tran smitter and so on.The Japanese horizontal river company uses various guides corrosion tech no logy to carry on the high accuracy three dime nsional process ing; the system helps the silic on res onance type pressure tran

41、 smitter. The core partially presses two res onant Lia ng by the feeli ng which above the silic on diaphragm and the silicon diaphragm manufactures to form, two resonant Liangs freque ncy differe nee corresp ondence differe nt pressure, measures the pressure with the frequency differenee method, may

42、 eliminate the error which factor and so on ambie nt temperature brin gs. Whe n ambie nt temperature cha nge, two resonant Liang frequencies and the amplitude variation are same, after two freque ncy differe nces, its same cha nge qua ntity can coun terbala nee mutually. It s survey most high accura

43、cy may reach 0.01%FS.American Silicon Microstructure Inc.(SMI) the company develops a series of low ends, linear in 0.1% to 0.ln 65% scope silicon micro pressure transmitter, the lowest full measuring range is 0.15psi (1KPa), it makes take the silic on as the material, has the unique three dime nsio

44、nal structure, the li ght slight machine-finishing, makes the wheat stone bridge many times with the etching on the silicon diaphragm, when above silicon chip stress, it has the distorti on, the resista nee produces presses the an ti- effect but to lose the bridge balanee, the output and the pressur

45、e becomes the proportion the electrical sig nal.Such silic on micro sen sor is the front tech no logy which now the sen sor develops, Its essential feature is the sensitive unit volume is a micron magn itude, Is the traditi onal sen sor several doze ns, several 1%. In aspect and so on industry contr

46、ol, aerospace domain, biomedicine has the vital role, like on the airplane the use may reduce the airplane weight, reduces the energy. Another characteristic is can be sensitive is small surveyed, may make the blood pressure pressure tran smitter.The Chinese aviation main corporation Beijing observa

47、tion and control technical research institute, the development CYJ series splashes thanks the membrane pressure transmitter is uses the ion sputtering craft to process the metal strain gauge, it has over come the nonmetallic strain gauge easily the temperature in flue nee in sufficie ncy, has the hi

48、gh stability, is suitable in each kind of situati on, is measured the medium scope widely, but also overcame the tradition lowly to glue the precision which the type brought, sluggish big, shortco ming and so on slow cha nge, had the precisi on high, the re-liability is high, the volume small charac

49、teristic, widely used in domain and so on aviati on, petroleum, chemical in dustry, medical service.Integrates the sensor the superiority is the traditional sensor is unable to achieve, it is a simple sensor not merely, itin at the same time the auxiliarycircuit part and send the part will integrate

50、 on together the chip, will causeitto have the calibrati on, to compe nsate, from the diag no sis and the n etwork corresp ondence function, it might reduce the cost, the gain in yield, this kind of blood pressure sensor whichAmericanLUCAS, NOVASENSORCorporation will develop, each week will be able

51、to produce 10,000.The intellectualized sensor is one kind of belt microprocessor sensor, is achievement which the microcomputer and the sensor unifies, it has at the same time the exam in ati on, the judgme nt and the in formati on process ing fun cti on, compares with the traditi onal sen sor has v

52、ery many characteristics:Has the judgme nt and the in formati on process ing function, can carry on the revision, the error to the observed value compensates, thus enhancement measuring accuracy; May realize the multi-sensor multi parameters survey; Has from the diag no sis and from the calibrati on

53、 fun ctio n, enhan ces the reliability; The survey data may deposit and withdraw, easy to operate; Has the data com muni cati onin terface, can and the microcomputer directcom muni cati on.The sen sor, the sig nal adjustme nt electric circuit, the mono lithic in tegrated circuit integration forms ul

54、tra large-scale integrated on a chip the senior in tellige nee sen sor. American HONY WELL Corporatio n ST-3000 in tellige nee3sen sor, the chip size only the n has 3X4X2mm , uses the semic on ductor craft, makes CPU, EPROM, the static pressure, the differential pressure, the temperature on the iden

55、tical chip and so on three kind of sensitive units.The intellectualized sensor research and the development, US is at the leadi ng positi on. America n Space Age ncy whe n developme nt spaceship called this kind of sen sor for the clever sen sor (Smart Sen sor), on the spaceship this kind of sen sor

56、 is extremely importa nt. Our country in this aspect research and developme nt also very backward mainly is because our country semic on ductor in tegrated circuit tech no logical level is limited.The sensor development is changing day after day since especially the 80s humanities have entered into

57、the high industrializationthe informationage, sen sor tech no-logy to ren ewal, higher tech no logical developme nt. US, Japa n and so on developed country sen sor tech no logical developme nt quickest, our country because the foun datio n is weak, the sen sor tech no logy compares with these develo

58、ped countries has the big disparity. Therefore, we should enlarge to the sensor engineering research, the development investment, causes our country sen sor tech no logy and the foreig n disparity reduces, promotes our country instrument measuring applianee industry and from the tech ni cal developm

59、e nt.FromSen sor Tech no logy Han dbook,J on Wilso n, New nes传感器新技术的发展传感器是一种能将物理量、化学量、生物量等转换成电信号的器件。输出信 号有不同形式，如电压、电流、频率、脉冲等，能满足信息传输、处理、记录、 显示、控制要求，是自动检测系统和自动控制系统中不可缺少的元件。如果把计 算机比作大脑，那么传感器则相当于五官，传感器能正确感受被测量并转换成相 应输出量，对系统的质量起决定性作用。自动化程度越高，系统对传感器要求越 高。传感器的几个关键词：1传感器元件除特例外，大多数的传感器都由敏感元件、转换元件或控制元件组成。如振 动膜、波纹