测控技术与仪器专业传感器新技术的发展毕业论文外文文献翻译及原文

测控技术与仪器专业传感器新技术的发展毕业论文外文文献翻译及原文
测控技术与仪器专业传感器新技术的发展毕业论文外文文献翻译及原文

毕业设计(论文)外文文献翻译

文献、资料中文题目:传感器新技术的发展

文献、资料英文题目:Development of Sensor New Technology 文献、资料来源:

文献、资料发表(出版)日期:

院(部):

专业:测控技术与仪器

班级:

姓名:

学号:

指导教师:

翻译日期: 2017.02.14

Development of Sensor New Technology

Sensor 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 Elements

Although 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 Sensitivity

The 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 Sensor

The 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 Sensor

Electrical 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 types

These 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 types

These 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 Sensor

Resistance 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 Sensor

The 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 Sensor

The 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)accuracy±0.1% of full scale is quoted

(iii)displacement ranges 25*10-6 m to 10-3m

(iv)rise time less than 50us possible

Typical measurands are displacement, pressure, vibration, sound, and liquid level.

5 Linear Variable-differential Ttransformer

6 Piezo-electric Sensor

7 Electromagnetic Sensor

8 Thermoelectric Sensor

9 Photoelectric Cells

10 Mechanical Sensor and Sensing Elements

In information age, the information industry includes information gathering, transmission, process three parts, namely sensor technology, communication, computer technology. Because of ultra large scale integrated circuit’s 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 technology’s 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 sensor’s 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 ray’s 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

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