1、Sensor technology A sensor is a device which produces a signal in response to its detecting or measuring a property ,such as position , force , torque , pressure , temperature , humidity , speed , acceleration , or vibration .Traditionally ,sensors (such as actuators and switches )have been used to
2、set limits on the performance of machines .Common examples are (a) stops on machine tools to restrict work table movements ,(b) pressure and temperature gages with automatics shut-off features , and (c) governors on engines to prevent excessive speed of operation . Sensor technology has become an im
3、portant aspect of manufacturing processes and systems .It is essential for proper data acquisition and for the monitoring , communication , and computer control of machines and systems . Because they convert one quantity to another , sensorsoften are referred to as transducers .Analog sensors produc
4、e a signal , such as voltage ,which is proportional to the measured quantity .Digital sensors have numeric or digital outputs that can be transferred to computers directly .Analog-to-coverter(ADC) is available for interfacing analog sensors with computers . Classifications of Sensors Sensors that ar
5、e of interest in manufacturing may be classified generally as follows: Machanical sensors measure such as quantities as positions ,shape ,velocity ,force ,torque , pressure , vibration , strain , andmass . Electrical sensors measure voltage , current , charge , and conductivity . Magnetic sensors me
6、asure magnetic field ,flux , and permeablity . Thermal sensors measure temperature , flux ,conductivity , and special heat . Other types are acoustic , ultrasonic , chemical , optical , radiation , laser ,and fiber-optic . Depending on its application , a sensor may consist of metallic , nonmetallic
7、 , organic , or inorganic materials , as well as fluids ,gases ,plasmas , or semiconductors .Using the special characteristics of these materials , sensors covert the quantity or property measured to analog or digital output. The operation of an ordinary mercury thermometer , for example , is based
8、on the difference between the thermal expansion of mercury and that of glass. Similarly , a machine part , a physical obstruction , or barrier in a space can be detected by breaking the beam of light when sensed by a photoelectric cell . A proximity sensor ( which senses and measures the distance be
9、tween it and an object or a moving member of a machine ) can be based on acoustics , magnetism , capacitance , or optics . Other actuators contact the object and take appropriate action ( usually by electromechanical means ) . Sensors are essential to the conduct of intelligent robots , and are bein
10、g developed with capabilities that resemble those of humans ( smart sensors , see the following ). This is America, the development of such a surgery Lin Bai an example, through the screen, through a remote control operator to control another manipulator, through the realization of the right abdomin
11、al surgery A few years ago our country the exhibition, the United States has been successful in achieving the right to the heart valve surgery and bypass surgery. This robot has in the area, caused a great sensation, but also, AESOPs surgical robot, In fact, it through some equipment to some of the
12、lesions inspections, through a manipulator can be achieved on some parts of the operation Also including remotely operated manipulator, and many doctors are able to participate in the robot under surgery Robot doctor to include doctors with pliers, tweezers or a knife to replace the nurses, while li
13、ghting automatically to the doctors movements linked, the doctor hands off, lighting went off, This is very good, a doctors assistant. Tactile sensing is the continuous of variable contact forces , commonly by an array of sensors . Such a system is capable of performing within an arbitrary three-dim
14、ensional space .has gradually shifted from manufacturing to non-manufacturing and service industries, we are talking about the car manufacturer belonging to the manufacturing industry, However, the services sector including cleaning, refueling, rescue, rescue, relief, etc. These belong to the non-ma
15、nufacturing industries and service industries, so here is compared with the industrial robot, it is a very important difference. It is primarily a mobile platform, it can move to sports, there are some arms operate, also installed some as a force sensor and visual sensors, ultrasonic ranging sensors
16、, etc. Its surrounding environment for the conduct of identification, to determine its campaign to complete some work, this is service robots one of the basic characteristics In visual sensing (machine vision , computer vision ) , cameral optically sense the presence and shape of the object . A micr
17、oprocessor then processes the image ( usually in less than one second ) , the image is measured , and the measurements are digitized ( image recognition ) .Machine vision is suitable particularly for inaccessible parts , in hostile manufacturing environments , for measuring a large number of small f
18、eatures , and in situations where physics contact with the part may cause damage . Small sensors have the capability to perform a logic function , to conduct two-way communication , and to make a decisions and take appropriate actions . The necessary input and the knowledge required to make a decisi
19、on can be built into a smart sensor . For example , a computer chip with sensors can be programmed to turn a machine tool off when a cutting tool fails . Likewise , a smart sensor can stop a mobile robot or a robot arm from accidentally coming in contact with an object or people by using quantities
20、such as distance , heat , and noise . Sensor fusion . Sensor fusion basically involves the integration of multiple sensors in such a manner where the individual data from each of the sensors ( such as force , vibration , temperature , and dimensions ) are combined to provide a higher level of inform
21、ation and reliability . A common application of sensor fusion occurs when someone drinks a cup of hotcoffee . Although we take such a quotidian event for granted ,it readily can be seen that this process involves data input from the persons eyes , lips , tongue , and hands .Through our basic senses
22、of sight , hearing , smell , taste , and touch , there is real-time monitoring of relative movements , positions , and temperatures . Thus if the coffee is too hot , the hand movement of the cup toward the lip is controlled and adjusted accordingly . The earliest applications of sensor fusion were i
23、n robot movement control , missile flight tracking , and similar military applications . Primarily because these activities involve movements that mimic human behavior . Another example of sensor fusion is a machine operation in which a set of different butintegrated sensors monitors (a) the dimensi
24、ons and surface finish of workpiece , (b) tool forces , vibrations ,and wear ,(c) the temperature in various regions of the tool-workpiece system , and (d) the spindle power . An important aspect in sensor fusion is sensor validation : the failure of one particular sensor is detected so that the con
25、trol system maintains high reliability . For this application ,the receiving of redundant data from different sensors is essential . It can be seen that the receiving , integrating of all data from various sensors can be a complex problem . With advances in sensor size , quality , and technology and
26、 continued developments in computer-control systems , artificial neural networks , sensor fusion has become practical and available at low cost .Movement is relatively independent of the number of components, the equivalent of our body, waist is a rotary degree of freedomWe have to be able to hold h
27、is arm, Arm can be bent, then this three degrees of freedom, Meanwhile there is a wrist posture adjustment to the use of the three autonomy, the general robot has six degrees of freedom. We will be able to space the three locations, three postures, the robot fully achieved, and of course we have les
28、s than six degrees of freedom Fiber-optic sensors are being developed for gas-turbine engines . These sensors will be installed in critical locations and will monitor the conditions inside the engine , such as temperature , pressure , and flow of gas . Continuous monitoring of the signals from thes
29、sensors will help detect possible engine problems and also provide the necessary data for improving the efficiency of the engines . 传感器技术 传感器一种通过检测某一参数而产生信号的装置。这一参数可以是位置、力、 力矩、压力、温度、湿度、速度、加速度或震动。从传统意义上来说，传感器（比 如执行器、开关）可用于限制机器参数的极限位置。常见的传感器有(a)限制工 作台运动的机床停止开关，(b)具有自动关闭功能的压力仪表和温度仪表， （c） 防止速度超限的调速器。传感器
30、技术已成为制造过程和系统的重要方面。它对于 数据的正确采集、机器和系统的检测、通讯以及计算机控制是很必要的。 传感器能够将一种物理量转换为另一种物理量，因此，传感器通常（被看作） 指转换器。模拟传感器产生信号，比如电压信号，该信号与被测物理力量成一定 比例。数字传感器具有数字输出，该数字输出能够直接被传递到计算机上。模数 转换器能够在模拟传感器和计算机之间起到接口作用。 传感器的分类 在制造业中，传感器可以分为以下几类：机械类传感器可以用来测量位置、形 状、速度、力、力矩、压力、震动、应变和质量。电器类传感器可以用来测量电 压、电流、电荷、电传导率。磁传感器可以用来测量磁场、磁通量、磁导率。热
31、 传感器可以用来测量温度、热流、热传导率以及特殊热量。其他类型的传感器有 声学传感器、超声波传感器、化学传感器、光学传感器、放射传感器、激光传感 器、光纤传感器。 根据应用的不同，传感器可以由金属材料、非金属材料、有机材料、无机材料 以及流体、气体、等离子体和半导体构成。利用这些材料的不同特性，传感器将 被测的物理量或参数转换为模拟信号或数字信号输出。比如，普通的水银温度计 的工作原理就是根据水银和玻璃的热膨胀率的不同而工作的。 类似地，当机器某一零件、物体障碍物、被测量与传感器空间中的障碍物遮挡 住光束时，就可被光电器件感知并检测到。接近开关（指感知并测量开关与物体 或机器的运动之间的距离）
32、可根据声学、磁学、电容、光学原理工作。其他执行 器依靠接触物体来执行相应的操作（通常机电一体化的方法） 。传感器对于智能 机器人的控制是不可缺少的， 并且通过模仿人类， 传感器的特性得到了很大发展。 触觉传感技术通过一组传感器可以连续不断的测量接触力的变化。 这样一个系 统能够监控任意的三维空间。 在视觉传感器（机器视觉，计算机视觉）中，光学摄像头感知物体的存在以及 物体的形状。接着，微处理器处理图像（通常不到1 秒）和测量图像，并且该测 量是数字化的（这一过程被称之为图像识别） 。机器视觉传感器特别适用于不能 直接接触到的零件的测量，恶劣的制造环境，大量微小特性的测量以及与零件的 物理接触会
33、造成零件破换的情况。 智能传感器能够执行逻辑功能，进行双向通讯，作出判断并执行相应的操作。 必要的输入和作出判断所需的条件被固化到智能传感器中。比如，带有传感器的 计算机芯片能够编程，当刀具失效时，能够自动地使机床停下来。同样地，如果 移动机器人与物体突然接触放生碰撞时，智能传感器就可以通过检测像距离、热 量、噪声这些参数使移动机器人或机械臂停止。 传感器融合技术。传感器融合技术主要指将多种传感器以一定的方式组合起 来，将每一个传感器的数据（比如力、震动、温度、维数）整合起来，获得更高 级别的的信息和可靠性。传感器融合技术的一个常见应用是喝一杯热咖啡。尽管 我们将这样一个平凡的小事认为是理所当
34、然的事，但我们很容易地观察到，这样 一个过程涉及到了从眼睛、 嘴唇、 舌头、 手的数据输入， 通过我们最基本的视觉、 听觉、嗅觉、触觉，就可以实时监测相对运动、位以及温度。这样，如果咖啡太 热，我们端茶杯草嘴唇的手的运动就会被控制并作出相应的调整。 传感器融合技术最早应用于机器人的移动控制、 导弹的飞行追踪和类似的军事 运用上， 这主要是因为这些检测活动是在模仿人的行为。传感器融合技术应用的 另一个例子是机床操作。在机床操作中， 有一整套不同类型而又集合在一起的传 感器，用于监控（a）工作的维度和表面光洁度（表面处理？） ，(b)=切削力、震 动、磨损，(c)刀具-工件系统各部分的温度以及轴的
35、（传递）功率。 传感器融合技术的一个重要方面是传感器（工作状态）的确认，即某一传感器 失效时就可被检测出来，从而使控制系统保持高的可靠性。从应用的角度讲，接 收来自不同传感器的多余参数是有必要的。可以看出，组成各种各样的传感器的 所有数据的接收、整合、处理时一个复杂的问题。 随着传感器尺寸的不断减小、传感器质量的不断提高、传感器技术的不断被进 步， 以及计算机控制系统、 人工智能、 专家系统和人工神经网络技术的不断发展， 传感器融合技术已变得切实可行并能以较低的成本获得。 光纤传感器用于汽轮机发动机，并不断得到发展。这些光线传感器安装在发动 机的关键部位，监控发动机的内部环境，比如温度、压力、气流。光纤传感器连 续不断的监控信号将有助于检测出潜在的发动机故障问题， 并可提供必要的数据 用于提高发动机的工作效率。
