光電傳感器英文和譯文

1、progress in materials science volume 46, issues 34, 2001, pages 461504 the selection of sensors j shieh, j.e huber, n.a fleck, , m.f ashby department of engineering, cambridge university, trumpington street, cambridge cb2 1pz, uk available online 14 march 2001. /10.1016/s0079-6425(00

2、)00011-6, how to cite or link using doi permissions selection; sensing range; sensing resolution; sensing frequency 1. introduction the oxford english dictionary defines a sensor as “a device which detects or measures some condition or property, and records, indicates, or otherwise responds to the i

3、nformation received”. thus, sensors have the function of converting a stimulus into a measured signal. the stimulus can be mechanical, thermal, electromagnetic, acoustic, or chemical in origin (and so on), while the measured signal is typically electrical in nature, although pneumatic, hydraulic and

4、 optical signals may be employed. sensors are an essential component in the operation of engineering devices, and are based upon a very wide range of underlying physical principles of operation. given the large number of sensors on the market, the selection of a suitable sensor for a new application

5、 is a daunting task for the design engineer: the purpose of this article is to provide a straightforward selection procedure. the study extends that of huber et al. 1 for the complementary problem of actuator selection. it will become apparent that a much wider choice of sensor than actuator is avai

6、lable: the underlying reason appears to be that power-matching is required for an efficient actuator, whereas for sensors the achievable high stability and gain of modern-day electronics obviates a need to convert efficiently the power of a stimulus into the power of an electrical signal. the classe

7、s of sensor studied here are detailed in the appendices. 2. sensor performance charts in this section, sensor performance data are presented in the form of 2d charts with performance indices of the sensor as axes. the data are based on sensing systems which are currently available on the market. the

8、refore, the limits shown on each chart are practical limits for readily available systems, rather than theoretical performance limits for each technology. issues such as cost, practicality (such as impedance matching) and reliability also need to be considered when making a final selection from a li

9、st of candidate sensors. before displaying the charts we need to introduce some definitions of sensor characteristics; these are summarised in table 1.1 most of these characteristics are quoted in manufacturers data sheets. however, information on the reliability and robustness of a sensor are rarel

10、y given in a quantitative manner. table 1. summary of the main sensor characteristics rangemaximum minus minimum value of the measured stimulus resolutionsmallest measurable increment in measured stimulus sensing frequencymaximum frequency of the stimulus which can be detected accuracyerror of measu

11、rement, in% full scale deflection sizeleading dimension or mass of sensor opt environmentoperating temperature and environmental conditions reliabilityservice life in hours or number of cycles of operation drift long term stability (deviation of measurement over a time period) costpurchase cost of t

12、he sensor ($ in year 2000) full-size table in the following, we shall present selection charts using a sub-set of sensor characteristics: range, resolution and frequency limits. further, we shall limit our attention to sensors which can detect displacement, acceleration, force, and temperature.2 eac

13、h performance chart maps the domain of existence of practical sensors. by adding to the chart the required characteristics for a particular application, a subset of potential sensors can be identified. the optimal sensor is obtained by making use of several charts and by considering additional tabul

14、ar information such as cost. the utility of the approach is demonstrated in section 3, by a series of case studies. 2.1. displacement sensors consider first the performance charts for displacement sensors, with axes of resolution versus range r, and sensing frequency f versus range r, as shown in fi

15、g. 1 and fig. 2, respectively. fig. 1. resolution versus sensing range for displacement sensors. view thumbnail images fig. 2. sensing frequency versus sensing range for displacement sensors. view thumbnail images 2.1.1. resolution sensing range chart (fig. 1) the performance regime of resolution ve

16、rsus range r for each class of sensor is marked by a closed domain with boundaries given by heavy lines (see fig. 1). the upper limit of operation is met when the coarsest achievable resolution equals the operating range =r. sensors of largest sensing range lie towards the right of the figure, while

17、 sensors of finest resolution lie towards the bottom. it is striking that the range of displacement sensor spans 13 orders of magnitude in both range and resolution, with a large number of competing technologies available. on these logarithmic axes, lines of slope +1 link classes of sensors with the

18、 same number of distinct measurable positions, . sensors close to the single position line =r are suitable as simple proximity (on/off) switches, or where few discrete positions are required. proximity sensors are marked by a single thick band in fig. 1: more detailed information on the sensing rang

19、e and maximum switching frequency of proximity switches are summarised in table 2. sensors located towards the lower right of fig. 1 allow for continuous displacement measurement, with high information content. displacement sensors other than the proximity switches are able to provide a continuous o

20、utput response that is proportional to the targets position within the sensing range. fig. 1 shows that the majority of sensors have a resolving power of 103106 positions; this corresponds to approximately 1020 bits for sensors with a digital output. table 2. specification of proximity switches prox

21、imity switch type maximum switching distance (m) maximum switching frequency (hz) inductive 6104110155000 capacitive 110361021200 magnetic 31038.51024005000 pneumatic cylinder sensors (magnetic) piston diameter 8103 3.2101 3005000 ultrasonic 1.21015.2150 photoelectric 31033002020,000 full-size table

22、 it is clear from fig. 1 that the sensing range of displacement sensors cluster in the region 105 101 m. to the left of this cluster, the displacement sensors of afm and stm, which operate on the principles of atomic forces and current tunnelling, have z-axis-sensing ranges on the order of microns o

23、r less. for sensing tasks of 10 m or above, sensors based on the non-contacting technologies of linear encoding, ultrasonics and photoelectrics become viable. optical linear encoders adopting interferometric techniques can achieve a much higher resolution than conventional encoders; however, their s

24、ensing range is limited by the lithographed carrier (scale). a switch in technology accounts for the jump in resolution of optical linear encoders around the sensing range of 0.7 m in fig. 1. note that “radar”, which is capable of locating objects at distances of several thousand kilometres,3 is not

25、 included in fig. 1. radar systems operate by transmitting high-frequency radio waves and utilise the echo and doppler shift principles to determine the position and speed of the target. generally speaking, as the required sensing range increases, sensors based on non-contact techniques become the m

26、ost practicable choice due to their flexibility, fast sensing speed and small physical size in relation to the length scale detected. fig. 1 shows that sensors based on optical techniques, such as fibre-optic, photoelectric and laser triangulation, cover the widest span in sensing range with reasona

27、bly high resolution. for displacement sensors, the sensing range is governed by factors such as technology limitation, probe (or sensing face) size and the material properties of the target. for example, the sensing distance of ultrasonic sensors is inversely proportional to the operating frequency;

28、 therefore, a maximum sensing range cut-off exists at about r=50 m. eddy current sensors of larger sensing face are able to produce longer, wider and stronger electromagnetic fields, which increase their sensing range. resolution is usually controlled by the speed, sensitivity and accuracy of the me

29、asuring circuits or feedback loops; noise level and thermal drift impose significant influences also. sensors adopting more advanced materials and manufacturing processes can achieve higher resolution; for example, high-quality resistive film potentiometers have a resolution of better than 1 m over

30、a range of 1 m (i.e. 106 positions) whereas typical coil potentiometers achieve only 103 positions. 2.1.2. sensing frequency sensing range chart (fig. 2) when a displacement sensor is used to monitor an oscillating body, a consideration of sensing frequency becomes relevant. fig. 2 displays the uppe

31、r limit of sensing frequency and the sensor range for each class of displacement sensor. it is assumed that the smallest possible sensing range of a displacement sensor equals its resolution; therefore in fig. 2, the left-hand side boundary of each sensor class corresponds to its finest resolution.4

32、 however, sensors close to this boundary are only suitable as simple switches, or where few discrete positions are to be measured. lines of slope 1 in fig. 2 link classes of sensors with the same sensing speed, fr. for contact sensors such as the lvdt and linear potentiometer, the sensing speed is l

33、imited by the inertia of moving parts. in contrast, many non-contact sensors utilise mechanical or electromagnetic waves and operate by adopting the time-of-flight approach; therefore, their maximum sensing speed is limited by the associated wave speed. for example, the maximum sensing speed of magn

34、etostrictive sensors is limited by the speed of a strain pulse travelling in the waveguide alloy, which is about 2.8103 m s1. the sensing frequency of displacement sensors is commonly dependent on the noise levels exhibited by the measuring electronic circuits. additionally, some physical and mechan

35、ical limits can also impose constraints. for example, the dynamic response of a strain gauge is limited by the wave speed in the substrate. for sensors with moving mass (for example, linear encoder, lvdt and linear potentiometer), the effects of inertial loading must be considered in cyclic operatio

36、n. for optical linear encoders the sensing frequency increases with range on the left-hand side of the performance chart, according to the following argument. the resolution becomes finer (i.e. decreases in an approximately linear manner) with a reduced scan speed v of the recording head. since the

37、sensor frequency f is proportional to the scan speed v, we deduce that f increases linearly with , and therefore f is linear in the minimum range of the device. 2.2. linear velocity sensors although velocity and acceleration are the first and second derivatives of displacement with respect to time,

38、velocity and acceleration measurements are not usually achieved by time differentiation of a displacement signal due to the presence of noise in the signal. the converse does not hold: some accelerometers, especially navigation-grade servo accelerometers, have sufficiently high stability and low dri

39、ft that it is possible to integrate their signals to obtain accurate velocity and displacement information. the most common types of velocity sensor of contacting type are electromagnetic, piezoelectric and cable extension-based. electromagnetic velocity sensors use the principle of magnetic inducti

40、on, with a permanent magnet and a fixed geometry coil, such that the induced (output) voltage is directly proportional to the magnets velocity relative to the coil. piezo-velocity transducers (pvts) are piezoelectric accelerometers with an internal integration circuit which produces a velocity signa

41、l. cable extension-based transducers use a multi-turn potentiometer (or an incremental/absolute encoder) and a tachometer to measure the rotary position and rotating speed of a drum that has a cable wound onto it. since the drum radius is known, the velocity and displacement of the cable head can be

42、 determined.5 optical and microwave velocity sensors are non-contacting, and utilise the optical-grating or doppler frequency shift principle to calculate the velocity of the moving target. typical specifications for each class of linear velocity sensor are listed in table 3. table 3. specification

43、of linear velocity sensors sensor class maximum sensing range (m/s) resolution (number of positions) maximum operating frequency (hz) magnetic induction25360 510451051001500 pvt 0.251.3110551057000 sensor class maximum sensing range (m/s) resolution (number of positions) maximum operating frequency

44、(hz) cable-extension 0.715110511061100 optical and microwave 131651105 10,000 目錄目錄 1. 簡(jiǎn)介簡(jiǎn)介.2 2. 傳感器性能圖表傳感器性能圖表.2 2.1位移傳感器位移傳感器 .3 2.1.1分辨率 - 感應(yīng)范圍圖（圖 1）.4 2.1.2.檢測(cè)頻率 檢測(cè)范圍圖（圖 2）.5 2.2線性速度傳感器線性速度傳感器 .6 問題 3-4，2001 年第 46 卷，頁(yè) 461-504 傳感器的選擇 j shieh, j.e huber, n.a fleck m.f ashby 劍橋大學(xué)工程系，英國(guó)劍橋 cb2 的 1pz，t

45、rumpington 街 _ 摘要摘要 對(duì)于一個(gè)特定的應(yīng)用系統(tǒng)來說要選擇最為合適的傳感器。大量種類的傳感 器存在，并且許多傳感器是基于耦合的電氣和機(jī)械現(xiàn)象，如壓電，磁致伸縮和 焦電效應(yīng)。傳感器的性能圖表是從商用設(shè)備供應(yīng)商提供的數(shù)據(jù)而來。選擇適當(dāng) 的傳感器是基于傳感器的經(jīng)營(yíng)特色，以匹配應(yīng)用程序要求。最終的選擇是根據(jù) 外加的其他因素，如成本，阻抗匹配。這些案例研究說明了選拔程序。 關(guān)鍵詞關(guān)鍵詞 傳感器 選擇 感應(yīng)范圍 檢測(cè)分辨率 檢測(cè)頻率 _ 1. 簡(jiǎn)介簡(jiǎn)介 “牛津英語(yǔ)大辭典”定義傳感器“一個(gè)能夠檢測(cè)測(cè)量環(huán)境或一些變量，且 能夠記錄，顯示，或以其他方式收到信息的設(shè)備”。因此，傳感器具有將刺激 轉(zhuǎn)換

46、成可測(cè)量信號(hào)的功能。這些刺激可以是力學(xué)，熱學(xué)，電磁學(xué)，聲學(xué)，或起 源于化學(xué)（等）的刺激，而測(cè)得的信號(hào)通一般是電信號(hào)，雖然氣動(dòng)，液壓和光 信號(hào)也可以采用。基于廣泛而最基本物理原理的傳感器是工程設(shè)備中必不可少 的組成部分。 考慮到市場(chǎng)上種類繁多的傳感器，對(duì)于工程設(shè)計(jì)人員為一個(gè)新的應(yīng)用程序 選擇合適的傳感器是一項(xiàng)艱巨的任務(wù)：這篇文章的目的就是提供一套簡(jiǎn)單的挑 選步驟。本研究是對(duì)胡貝爾等對(duì)執(zhí)行機(jī)構(gòu)選擇問題的延伸和補(bǔ)充。傳感器比執(zhí) 行機(jī)構(gòu)具有更為廣泛的應(yīng)用：根本原因，驅(qū)動(dòng)器需要有效的比配功率，而傳感 器是實(shí)現(xiàn)現(xiàn)性電子產(chǎn)品所要求的的高穩(wěn)定性和增益性并能將其轉(zhuǎn)換成強(qiáng)有效的 電信號(hào)地刺激。傳感器種類的研究將在

47、附錄中詳細(xì)的闡述。 2. 傳感器性能圖表傳感器性能圖表 在本節(jié)中，傳感器性能數(shù)據(jù)以性能為橫軸的二維圖中進(jìn)行展示。這些數(shù)據(jù) 是基于當(dāng)前市場(chǎng)上一般可用的傳感系統(tǒng)的。而不是具有工藝?yán)碚撗芯康睦碚撝?識(shí)。如成本，實(shí)用性（如阻抗匹配）和可靠性等問題也需要從備選傳感器性能 列表中進(jìn)行對(duì)比，然后在做最后的選擇。 在闡釋圖表之前，我們需要介紹一些有關(guān)傳感器特性的定義，在表 1.1 中 給出的性能多是廠商會(huì)給出的。然而，傳感器的可靠性和魯棒性很少以確定 的方式給出 表 1.主要傳感器的特性總結(jié) 范圍刺激的最大值減最小值 分辨率可測(cè)量的最小的刺激變化值 檢測(cè)頻率可被檢測(cè)的刺激的最高頻率 精度測(cè)量誤差, 以滿課度百

48、分比的形式給出 尺寸一般傳感器的主要規(guī)格 外界環(huán)境溫度和環(huán)境條件 可靠性服務(wù)時(shí)長(zhǎng)活著運(yùn)行周期 漂移長(zhǎng)期穩(wěn)定性（一段時(shí)期內(nèi)的測(cè)量偏差） 成本采購(gòu)成本 (2000 年以美元計(jì)) 全尺寸表 在下面，我們將用二維的傳感器特性圖呈現(xiàn)選項(xiàng)：范圍，分辨率和頻率的限制。 此外，我們應(yīng)該限制我們的注意力集中于能夠測(cè)量距離，加速度，力，溫度的 的傳感器。 每個(gè)性能圖展示是的實(shí)際存在的應(yīng)用于各產(chǎn)業(yè)中的傳感器。通過在圖表中 添加為特定應(yīng)用所需的敏感器特性，可以識(shí)分辨出傳感器的子集。要想選擇出 最合適的傳感器是利用幾個(gè)圖表，并要考慮下面的表格信息如價(jià)格。該方法的 實(shí)用性表現(xiàn)在 2.1位移傳感器 首先考慮位移傳感器的性能

49、圖表，分辨率 與范圍 r 的關(guān)系，檢測(cè)頻率 f 與范 圍 r 的關(guān)系，如圖 1 和圖 2 分別所示。 圖 1。位移傳感器的分辨率與傳感范圍的對(duì)應(yīng)系。 圖 2。位移傳感器的檢測(cè)頻率與傳感范圍的對(duì)應(yīng)關(guān)系。 2.1.1分辨率 - 感應(yīng)范圍圖（圖 1） 對(duì)于這種傳感器的分辨率對(duì)感應(yīng)范圍 r 的性能結(jié)構(gòu)是用封閉的的加重的線標(biāo)記 的（見圖一）。當(dāng)可感應(yīng)的分辨率等于感應(yīng)范圍即 = r 是，。令人吃驚的位 移傳感器的范圍跨越 13 個(gè)數(shù)量級(jí)，大量的競(jìng)爭(zhēng)技術(shù)，在范圍和分辨率。在這 些數(shù)軸，斜坡+1 傳感器具有獨(dú)特的可衡量的職位相同數(shù)量的鏈接類線。接近傳 感器，以單一的立場(chǎng)是一致的是適合作為簡(jiǎn)單的接近（開/關(guān)）開

50、關(guān)，或需要幾 個(gè)分立位置。接近傳感器是由一個(gè)單一的厚圖帶標(biāo)記。 1：最大開關(guān)頻率接近 開關(guān)感應(yīng)范圍和更詳細(xì)的信息匯總表 2。對(duì)位于圖右下角的傳感器。 1 允許連 續(xù)位移測(cè)量，信息含量高。位移傳感器，接近開關(guān)以外，能夠提供連續(xù)的輸出 響應(yīng)是成正比的感應(yīng)范圍內(nèi)目標(biāo)的位置。圖 1 可以看出，大多數(shù)傳感器有 103- 106 位置的分辨能力，這對(duì)應(yīng)約 10-20 位數(shù)字輸出的傳感器。 表 2。接近開關(guān)的規(guī)格 接近開關(guān)類型最大開關(guān)距離 (m)最大開關(guān)頻率（hz） 感應(yīng)區(qū)6104110155000 容量110361021200 磁性31038.51024005000 氣缸傳感器（磁）活塞 直徑超聲波 81033.21013005000 超聲波1.21015.2150 光電31033002020,000 全尺寸表 從圖 1 可以很明顯的看到位移傳感器的感應(yīng)范圍集中在 10-5-101 米的區(qū)域。這 個(gè)范圍左側(cè)，afm 和 stm 位移傳感器是靠原子力來運(yùn)行的，并且 z 軸感應(yīng)范 圍在微米級(jí)左右。對(duì)于測(cè)量 10 米或以上的傳感任務(wù)，傳感器基于非接觸式的 線性編碼的超聲波的光電技術(shù)。光學(xué)