传感器专业名词英文解释.docx
《传感器专业名词英文解释.docx》由会员分享,可在线阅读,更多相关《传感器专业名词英文解释.docx(15页珍藏版)》请在三一办公上搜索。
1、传感器专业名词英文解释1. Briefly define the following terms 1) Transducer A transducer is a device that converts a signal from one physical form to a corresponding signal having a different physical form . 2) Sensor A sensor converts a physical signal into an electrical signal (i.e., a microphone). 3) Actuator
2、 An actuator is a device that converts electrical energy into physical energy (i.e., a loudspeaker). 4) Linearity The linearity describes the closeness between the calibration curve and a specified straight line. 5) Sensitivity The sensitivity is defined in terms of the relationship between input ph
3、ysical signal and output electrical signal. It is generally the ratio between a small change in electrical signal to a small change in physical signal. The sensitivity is the slope of the calibration curve. 6) Hysteresis The hysteresis refers to the difference between two output values that correspo
4、nd to the same input, depending on the direction (increasing or decreasing) of successive input values. That is, similarly to the magnetization in ferromagnetic materials, it can happen that the output corresponding to a given input depends on whether the previous input was higher or lower than the
5、present one. Some sensors do not return to the same output value when the input stimulus is cycled up or down. The width of the expected error in terms of the measured quantity is defined as the hysteresis. 7) Repeatability The repeatability is the closeness of agreement between successive results o
6、btained with the same method under the same conditions and in a short time interval. R=(23)100%yFS sample standard deviation 8) Strain (mechanical) Fractional change in length L/L. 9) Gage factor The gage factor is defined as the fractional change in resistance divided by the strain. 10) Piezoresist
7、ive effect The change in resistivity as a result of a mechanical stress is called the piezoresistive effect. 11) direct piezoelectric effect. the phenomenon of generation of a voltage under mechanical stress is referred to as the piezoelectric effect. converse piezoelectric effect. The mechanical st
8、rain produced in the crystal under electric stress is called the converse piezoelectric effect. Numerical Aperture The acceptance cone defines how much light will be accepted into the fiber and ultimately how much remains in the fiber, and is referred to as the numerical aperture. Extrinsic sensor T
9、he optical fiber plays no part in achieving the modulating but simply acts as a transmission medium ; these are extrinsic sensors. Intrinsic sensors (fiber optic sensor) The optical fiber plays a major role in modulating the energy from the source; these are referred to as intrinsic sensors. Humidit
10、y 12) 13) 14) 15) 16) a quantity representing the amount of water vapor in the atmosphere or a gas 17) Absolute humidity Absolute humidity is the mass of water vapor per unit volume of air. 18) Relative humidity The ratio of the actual vapor density to the theoretical maximum (saturation) vapor dens
11、ity at the same temperature, expressed as a percentage. The relative humidity is the ratio of the actual vapor pressure to the saturation vapor pressure at given temperature. 19) Peltier effect When two dissimilar metals are connected together, a small voltage called a thermojunction voltage is gene
12、rated at the junction. This is called the Peltier effect. 20) Law of Homogeneous Conductors For a given pair of homogeneous conductors forming a closed loop, the Seebeck emf depends only on the temperatures of the junctions, and not on the temperature distribution along the length of the conductors.
13、 21) Law of intermediate metals A third (intermediate) metal wire can be inserted in series with one of the wires without changing the voltage reading (provided that the two new junctions are at the same temperature). If there is a third metal introduced into the thermocouple circuit , it will not a
14、dversely effect the reading, if and only if the two junctions of the third metal are at the same temperatures . 22) Bernoullis theorem Bernoullis equation states that energy is approximately conserved across a constriction in a pipe. Bernoullis equation: P/(g) + v2/g + y = constant (=density; g=acce
15、leration of gravity ; v=fluid velocity; y=elevation ) 2. Describe the following devices and how they work 1) Strain gage The strain gauge usually consists of wire, baking, thinpaper, and lead welded. The wire is arranged in the form of a grid in order to obtain higher resistances. 2) Parallel plate
16、Capacitive Sensor The parallel plate Capacitive Sensor is a function of the distance d (cm) between the electrodes of a structure, the surface area A (cm2) of the electrodes, and the permittivity 0 -128.8510F/mfor air) of the dielectric between the electrodes; therefore: (C=eAd=ere0Ad3) Differential
17、 Capacitive Sensor A differential capacitor consists of two variable capacitors so arranged that they undergo the same change, but in opposite directions. The amplifier circuit, depending on its configuration, can generate a voltage proportional to C1 - C2 or C1/C2 or (C1 - C2)/(C1 + C2). 4) Variabl
18、e Reluctance Sensors A typical single-coil variable-reluctance displacement sensor is illustrated in the Figure below. The sensor consists of three elements: a ferromagnetic core, a variable air gap, and a ferromagnetic plate. Based on change in the reluctance of a magnetic flux path. Self-inductanc
19、e L of the coil is: 2 L=WRm lR=Reluctance can be given as: m mm0S5) Variable-Reluctance Tachogenerators It consists of a ferromagnetic, toothed wheel attached to a rotating shaft, a coil and a magnet. The wheel rotates in close proximity to the pole piece, thus causing the flux linked by thecoil to
20、change. The sensors output depends on the speed of the rotation of the wheel and the number of teeth. 6) LVDT An LVDT consists of three coils, a form and a core. The coils are wound on a hollow form. The primary is excited by some ac source. Flux formed by the primary is linked to the two secondary
21、coils, inducing an ac voltage in each coil. A core is inside the former. It can slide freely through the center of the form. In many applications, the two secondary coils are connected in series opposition. Then the two voltages will subtract; that is, the differential voltage is formed. When the co
22、re is centrally located, the net voltage is zero. When the core is moved to one side, the net voltage will increase. 7) Compression Mode Piezoelectric Accelerometers Upright compression designs sandwich the piezoelectric crystal between a seismic mass and rigid mounting base. A pre- load stud or scr
23、ew secures the sensing element to the mounting base.When the sensor is accelerated, the seismic mass increases or decreases the amount of compression force acting upon the crystal, and a proportional electrical output results. 8) Shear mode accelerometer Shear mode accelerometer designs bond, or “sa
24、ndwich,” the sensing material between a center post and seismic mass. A compression ring or stud applies a preload force required to create a rigid linear structure. Under acceleration, the mass causes a shear stress to be applied to the sensing material. This stress results in a proportional electr
- 配套讲稿:
如PPT文件的首页显示word图标,表示该PPT已包含配套word讲稿。双击word图标可打开word文档。
- 特殊限制:
部分文档作品中含有的国旗、国徽等图片,仅作为作品整体效果示例展示,禁止商用。设计者仅对作品中独创性部分享有著作权。
- 关 键 词:
- 传感器 专业 名词 英文 解释
链接地址:https://www.31ppt.com/p-3269392.html