自動(dòng)化專(zhuān)業(yè)外文文獻(xiàn)

Development of Sensor New TechnologySensor is one kind component which can transform the physical quantity, chemistry quantity and the biomass into electrical signal. The output signal has the different forms like the voltage, the electric current, the frequency, the pulse and so on, which can satisfy the signal transmission, processing, recording, and demonstration and control demands. So it is the automatic detection system and in the automatic control industry .If automatic Technology is used wider, then sensor is more important.Several key words of the sensor：1 Sensor ElementsAlthough there are exception ,most sensor consist of a sensing element and a conversion or control element. For example, diaphragms,bellows,strain tubes and rings, bourdon tubes, and cantilevers are sensing elements which respond to changes in pressure or force and convert these physical quantities into a displacement. This displacement may then be used to change an electrical parameter such as voltage, resistance, capacitance, or inductance. Such combination of mechanical and electrical elements form electromechanical transducing devices or sensor. Similar combination can be made for other energy input such as thermal. Photo, magnetic and chemical,giving thermoelectric, photoelectric,electromaanetic, and electrochemical sensor respectively.2 Sensor SensitivityThe relationship between the measured and the sensor output signal is usually obtained by calibration tests and is referred to as the sensor sensitivity K1= output-signal increment / measured increment . In practice, the sensor sensitivity is usually known, and, by measuring the output signal, the input quantity is determined from input= output-signal increment / K1.3 Characteristics of an Ideal SensorThe high sensor should exhibit the following characteristics.(a)high fidelity-the sensor output waveform shape be a faithful reproduction of the measured; there should be minimum distortion.(b)There should be minimum interference with the quantity being measured; the presence of the sensor should not alter the measured in any way.(c)Size. The sensor must be capable of being placed exactly where it is needed.(d)There should be a linear relationship between the measured and the sensor signal.(e)The sensor should have minimum sensitivity to external effects, pressure sensor,for example,are often subjected to external effects such vibration and temperature.(f)The natural frequency of the sensor should be well separated from the frequency and harmonics of the measurand.Sensors can be divided into the following categories：1 Electrical SensorElectrical sensor exhibit many of the ideal characteristics. In addition they offer high sensitivity as well as promoting the possible of remote indication or mesdurement.Electrical sensor can be divided into two distinct groups:(a)variable-control-parameter types,which include:(i)resistance(ii)capacitance(iii)inductance(iv)mutual-inductance typesThese sensor all rely on external excitation voltage for their operation.(b)self-generating types,which include(i)electromagnetic(ii)thermoelectric(iii)photoemissive(iv)piezo-electric typesThese all themselves produce an output voltage in response to the measurand 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, the sensor exhibits the reversible effect by deforming or vibrating at the frequency of the alternating voltage.2 Resistance SensorResistance sensor may be divided into two groups, as follows:(i)Those which experience a large resistance change, measured by using potential-divider methods. Potentiometers are in this group.(ii)Those which experience a small resistance change, measured by bridge-circuit methods. Examples of this group include strain gauges and resistance thermometers.3 Capacitive SensorThe capacitance can thus made to vary by changing either the relative permittivity, 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.Unlike the potentionmeter, the variable-distance capacitive sensor has an infinite resolution making it most suitable for measuring small increments of displacement or quantities which may be changed to produce a displacement.4 Inductive SensorThe inductance can thus be made to vary by changing the reluctance of the inductive circuit.Measuring techniques used with capacitive and inductive sensor:(a)A.C. excited bridges using differential capacitors inductors.(b)A.C. potentiometer circuits for dynamic measurements.(c)D.C. circuits to give a voltage proportional to velocity for a capacitor.(d)Frequency-modulation methods, where the change of C or L varies the frequency of an oscillation circuit.Important features of capacitive and inductive sensor are as follows:(i)resolution infinite(ii)accuracy0.1% of full scale is quoted(iii)displacement ranges 25*10-6 m to 10-3m(iv)rise time less than 50us possibleTypical measurands are displacement, pressure, vibration, sound, and liquid level.5 Linear Variable-differential Ttransformer6 Piezo-electric Sensor7 Electromagnetic Sensor8 Thermoelectric Sensor9 Photoelectric Cells10 Mechanical Sensor and Sensing ElementsIn information age, the information industry includes information gathering, transmission, process three parts, namely sensor technology, communication, computer technology. Because of ultra large scale integrated circuits rapid development after having been developed Modern computer technology and communication, not only requests sensor precision reliability, 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, the volume, the cost and so on. As world develop many countries are speeding up to the sensor new technologys research and the development, and all has obtained the enormous breakthrough. Now the sensor new technology development mainly has following several aspects:Using the physical phenomenon, the chemical reaction, the biological effect as the sensor principle therefore the researches which discovered the new phenomenon and the new effect are the sensor technological improving ways .it is important studies to developed new sensors the foundation. Japanese Sharp Corporation uses the superconductivity technology to develop successfully the high temperature superconductivity magnetic sensor and get the sensor technology significant breakthrough. Its sensitivity is so high and only inferior in the superconductivity quantum interference component. Its manufacture craft is far simpler than the superconductivity quantum interference component. May use in magnetism image formation technology. So it has the widespread promoted value.Using the immune body and the antigen meets one another compound when the electrode surface. It can cause the electrode potential change and use this phenomenon to be possible to generate the immunity sensor. The immunity 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 whether contracts the hepatitis, plays to is fast, the accurate role. The US UC sixth branch has developed this kind of sensor.The sensor material is the important foundation for sensor technology, because the materials science is progressive and the people may make each kind of new sensor For example making the temperature sensor 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 sensors; Making the pressure transmitter with the ceramics. The high polymer can become the proportion adsorption and the release hydrogen along with the environment relative humidity size. The high polymer electricity lies between the constant to be small, the hydrogen can enhance the polymer the coefficient of dialectical loss. Making the capacitor the high polymer dielectric medium, determines the electric capacity cape city the change, then obtains the relative humidity. Making the plasma using this principle to gather the legitimate polystyrene film temperature sensor below, it has the characteristic.Measured the wet scope is wide; The temperature range is wide, may reach -400 +1,500 ; The speed of response is quick, is smaller than 1S; The size is small, may use in the small space measuring wet; The temperature coefficient is small.The ceramic electric capacity type pressure transmitter is one kind does not have the intermediary fluid the dry type pressure transmitter. Uses the advanced ceramic technology, the heavy film electronic technology, its technical performance is stable, the year drifting quantity is smaller than 0.1%F.S, warm floats is smaller than 0.15%/10K, anti- overloads strongly, may reach the measuring range several hundred times. The survey scope may from 0 to 60mpa.German E+H Corporation and the American Kahlo Corporation product is at the leading position.The optical fiber application is send the material significant breakthrough, its uses in most early the optical communication techniques. In the optical communication use discovered works as environmental condition change and so on the temperature, pres-sure, electric field, magnetic field, causes the fiber optic transmission light wave intensity, the phase, the frequency, change and so on the polarization condition, the survey light wave quantity change, may know causes these light wave physical quantity the and so on quantitative change temperature, pressure ,electric field, magnetic field size, uses these principles to be possible to develop the optical fiber sensor. The optical fiber sensor and the traditional sensor compare has many characteristics: Sensitivity high, the structure simple, the volume small, anti-corrosive, the electric insulation good, the path of rays may be curving, be advantageous for the realization telemeter and so on. Optical fiber sensor Japan is in the advanced level. Like Idec Izumi Corporation and Sun x Corporation. The optical fiber send receiver and the integrated path of rays technology unify, accelerates the optical fiber sensor technology development. Will integrate the path of rays component to replace the original optics part and the passive light component; enable the optical fiber sensor to have the high band width, the low signal processing voltage, the reliability high, the cost will be low.In semiconductor technology processing method oxygenation, the photo etc hang, the proliferation, the deposition, the plane electron craft, various guides corrosion and steams plates, the sputtering thin film and so on, these have all introduced to the sensor manufacture. Thus has produced each kind of new sensor, like makes the silicon micro sensor using the semiconductor technology, makes the fast response using the thin film craft the gas to be sensitive, the wet sensitive sensor, the use sputtering thin film craft system pressure transmitter and so on.The Japanese horizontal river company uses various guides corrosion technology to carry on the high accuracy three dimensional processing; the system helps the silicon resonance type pressure transmitter. The core partially presses two resonant Liang by the feeling which above the silicon diaphragm and the silicon diaphragm manufactures to form, two resonant Liangs frequency difference correspondence different pressure, measures the pressure with the frequency difference method, may eliminate the error which factor and so on ambient temperature brings. When ambient temperature change, two resonant Liang frequencies and the amplitude variation are same, after two frequency differences, its same change quantity can counterbalance mutually. Its survey most high accuracy may reach 0.01%FS.American Silicon Microstructure Inc.(SMI) the company develops a series of low ends, linear in 0.1% to 0.In 65% scope silicon micro pressure transmitter, the lowest full measuring range is 0.15psi (1KPa), it makes take the silicon as the material, has the unique three dimensional structure, the light 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 distortion, the resistance produces presses the anti- effect but to lose the bridge balance, the output and the pressure becomes the proportion the electrical signal.Such silicon micro sensor is the front technology which now the sensor develops, Its essential feature is the sensitive unit volume is a micron magnitude, Is the traditional sensor several dozens, several 1%. In aspect and so on industry control, 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 transmitter.The Chinese aviation main corporation Beijing observation 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 influence insufficiency, has the high stability, is suitable in each kind of situation, is measured the medium scope widely, but also overcame the tradition lowly to glue the precision which the type brought, sluggish big, shortcoming and so on slow change, had the precision high, the re-liability is high, the volume small characteristic, widely used in domain and so on aviation, petroleum, chemical industry, medical service.Integrates the sensor the superiority is the traditional sensor is unable to achieve, it is a simple sensor not merely, it in at the same time the auxiliary circuit part and send the part will integrate on together the chip, will cause it to have the calibration, to compensate, from the diagnosis and the network correspondence function, it might reduce the cost, the gain in yield, this kind of blood pressure sensor which American LUCAS, NOVASENSOR Corporation will develop, each week will be able 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 examination, the judgment and the information processing function, compares with the traditional sensor has very many characteristics:Has the judgment and the information processing 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 diagnosis and from the calibration function, enhances the reliability; The survey data may deposit and withdraw, easy to operate; Has the data communication interface, can and the microcomputer direct communication.The sensor, the signal adjustment electric circuit, the monolithic integrated circuit integration forms ultra large-scale integrated on a chip the senior intelligence sensor. American HONY WELL Corporation ST-3000 intelligence sensor, the chip size only then has 342mm3, uses the semiconductor craft, makes CPU, EPROM, the static pressure, the differential pressure, the temperature on the identical chip and so on three kind of sensitive units.The intellectualized sensor research and the development, US is at the leading position. American Space Agency when development spaceship called this kind of sensor for the clever sensor (Smart Sensor), on the spaceship this kind of sensor is extremely important. Our country in this aspect research and development also very backward mainly is because our country semiconductor integrated circuit technological level is limited.The sensors development is changing day after day since especially the 80s humanities have entered into the high industrialization the information age, sensor techno-logy to renewal, higher technological development. US, Japan and so on developed country sensor technological development quickest, our country because the foundation is weak, the sensor technology compares with these developed countries has the big disparity. Therefore, we should enlarge to the sensor engineering research, the development investment, causes our country sensor technology and the foreign disparity reduces, promotes our country instrument measuring appliance industry and from the technical development.FromSensor Technology Handbook,Jon Wilson,Newnes傳感器新技術(shù)的發(fā)展傳感器是一種能將物理量、化學(xué)量、生物量等轉(zhuǎn)換成電信號(hào)的器件。輸出信號(hào)有不同形式，如電壓、電流、頻率、脈沖等，能滿(mǎn)足信息傳輸、處理、記錄、顯示、控制要求，是自動(dòng)檢測(cè)系統(tǒng)和自動(dòng)控制系統(tǒng)中不可缺少的元件。如果把計(jì)算機(jī)比作大腦，那么傳感器則相當(dāng)于五官，傳感器能正確感受被測(cè)量并轉(zhuǎn)換成相應(yīng)輸出量，對(duì)系統(tǒng)的質(zhì)量起決定性作用。自動(dòng)化程度越高，系統(tǒng)對(duì)傳感器要求越高。傳感器的幾個(gè)關(guān)鍵詞：1傳感器元件除特例外，大多數(shù)的傳感器都由敏感元件、轉(zhuǎn)換元件或控制元件組成。如振動(dòng)膜、波紋管、應(yīng)力管和應(yīng)力環(huán)、低音管和懸臂都是敏感元件，它們對(duì)壓力和力作出響應(yīng)把物理量轉(zhuǎn)變成位移。然后位移可以改變電參數(shù)，如電壓、電阻、電容或者感應(yīng)系數(shù)。機(jī)械式和電子式元件合并形成機(jī)電式傳感設(shè)備或傳感器。這樣的組合可用來(lái)輸入能量信號(hào)。熱的，光的，磁的和化學(xué)的相互結(jié)合產(chǎn)生的熱電式、光電式、電磁式和電化學(xué)式傳感器。2 傳感器靈敏度通過(guò)校正測(cè)量系統(tǒng)獲得的被測(cè)物理量和傳感器輸出信號(hào)的關(guān)系叫做傳感器靈敏度K1，也就是K1=輸出信號(hào)增量/測(cè)量增量。實(shí)際中，傳感器的靈敏度是已知的，并且通過(guò)測(cè)量輸出信號(hào)，輸入量由下式?jīng)Q定，輸入量=輸出信號(hào)增量/K1。3 理想傳感器的特性（a）高保真性：傳感器輸出波形應(yīng)該真實(shí)可靠地再現(xiàn)被測(cè)量，并且失真很小。（b）可測(cè)量最小的干擾，任何時(shí)候傳感器的出現(xiàn)不能改變被測(cè)量。（c）尺寸：傳感器必須能正確地放在所需的地方。（d）被測(cè)量和傳感器信號(hào)之間應(yīng)該有一個(gè)線性關(guān)系。（e）傳感器對(duì)外部影響的靈敏度應(yīng)該小，例如壓力傳感器經(jīng)常受到外部振動(dòng)和溫度的影響。（f）傳感器的固有頻率應(yīng)該避開(kāi)被測(cè)量的頻率和諧波。傳感器可分為以下幾類(lèi)：1 電傳感器電傳感器具有許多理想特性。它們不僅實(shí)現(xiàn)遠(yuǎn)程測(cè)量和顯示，還能提供高靈敏度。電傳感器可分為兩大類(lèi)