测控专业英语8

1、Unit 8 New TechnologyAn Introduction to Robotics Technology The word “robot” originates from the Czech word for forced labor, or serf. It is introduced by playwright Karel Capek, whose fictional robotic inventions are much like Dr. Frankensteins monster-creatures created by chemical and biological,

2、rather than mechanical, methods. But the current mechanical robots of popular culture are not much different from these fictional biological creations. 句中句中forced labor, or serf意为意为“强迫劳动、奴隶强迫劳动、奴隶”，playwright 意为意为“剧作家剧作家”。An Introduction to Robotics Technology Basically a robot consists of:(1)A mech

3、anical device, such as a wheeled platform capable of interacting with its environment.(2)Sensors on or around the device that are able to sense the environment and give useful feedback to the device.(3)Systems that process sensory input in the context of the devices current situation and instruct th

4、e device to perform actions in response to the situation.An Introduction to Robotics Technology 译为：机器人是一种可以重复编程的、多功能的操作装置，通译为：机器人是一种可以重复编程的、多功能的操作装置，通过不同的程序，它可以移动材料、零件、工具或特殊装备，最过不同的程序，它可以移动材料、零件、工具或特殊装备，最终完成各种各样的任务。终完成各种各样的任务。Here is the definition of “robot” (from the Robot Institute of America, 19

5、79): A re-programmable, multifunctional manipulator designed to move material, parts, tools, or specialized devices through various programmed motions for the performance of a variety of tasks. Figure 8.1 shows an example of a robot.An Introduction to Robotics Technology A robot consists of two main

6、 parts: the robot body and some form of Artificial Intelligence (AI) system. Many different body parts can be called a robot. Articulated arms are used in welding and painting; gantry and conveyor systems move parts in factories; and giant robotic machines move earth deep inside mines. One of the mo

7、st interesting aspects of robots in general is their behavior, which requires a form of intelligence. The simplest behavior of a robot is locomotion. Typically, wheels are used as the underlying mechanism to make a robot move from one point to the next. And some force such as electricity is required

8、 to make the wheels turn under command. 句中句中Articulated arm意为意为“关节臂关节臂”， gantry and conveyor 意为意为“起重台架和输送机起重台架和输送机”， locomotion 意为意为“运动、移运动、移动动”。An Introduction to Robotics Technology (1)MotorsA variety of electric motors provide power to robots, allowing them to move material, parts, tools, or spec

9、ialized devices with various programmed motions. The efficiency rating of a motor describes how much of the electricity consumed is converted to mechanical energy. Lets take a look at some of the mechanical devices that are currently being used in modern robotics technology.DC motors: Permanent-Magn

10、et, Direct-Current (PMDC) motors require only two1eads, and use an arrangement of fixed-and electro-magnets (stator and rotor) and switches. These form a commutator to create motion through a spinning magnetic field.句中句中Permanent-Magnet意为意为“永磁永磁”， stator and rotor意为意为“定子和转子定子和转子”， commutator 意为意为“换向

11、器换向器”。An Introduction to Robotics Technology (1)MotorsAC motors: AC motors cycle the power at the input-leads, to continuously move the field. Given a signal, AC and DC motors perform their action to the best of their ability.Stepper motors: Stepper motors are like a brushless DC or AC motor. They m

12、ove the rotor by applying power to different magnets in the motor in sequence (stepped). Stepper are designed for fine control and will not only spin on command, but can spin at any number of steps-per-second (up to their maximum speed).An Introduction to Robotics Technology (1)MotorsServomotors: Se

13、rvomotors are closed-loop devices. Given a signal, they adjust themselves until they match the signal. Servos are used in radio control airplanes and cars. They are simple DC motors with gearing and a feedback control system.句中句中Servomotors意为意为“伺服电机伺服电机”。An Introduction to Robotics Technology (2) Dr

14、iving mechanisms Gears and chains: Gears and chains are mechanical platforms that provide a strong an accurate way to transmit rotary motion from one place to another, possibly changing it along the way. The speed change between two gears depends on the number of teeth on each gear. When a powered g

15、ear goes through a full rotation, it pulls the chain by the number of teeth on that gear.Pulleys and belts: Pulleys and belts, two other types of mechanical platforms used in robots, work the same way as gears and chains. Pulleys are wheels with a groove around the edge, and belts are the rubber loo

16、ps that fit in that groove.句中句中Gears and chains意为意为“齿轮和链齿轮和链”， Pulleys and belts 意意为为“带轮和带带轮和带”，groove意为意为“轮槽轮槽”。An Introduction to Robotics Technology (2) Driving mechanisms Gearboxes: A gearbox operates on the same principles as the gear and chain, without the chain. Gearboxes require closer toler

17、ances, since instead of using a large loose chain to transfer force and adjust for misalignments, the gears mesh directly with each other. Examples of gearboxes can be found on the transmission in a car, the timing mechanism in grandfather clock, and the paper-feed of your printer.句中句中tolerances意为意为

18、“公差公差”， mesh意为意为“啮合啮合”， grandfather clock意为意为“有摆的落地大座钟有摆的落地大座钟”，paper-feed意意为为“进纸系统进纸系统”。Truck gearboxesAn Introduction to Robotics Technology (3) Power supplies Power supplies are generally provided by two types of battery. Primary batteries are used once and then discarded; secondary batteries ope

19、rate from a (mostly) reversible chemical reaction and can be recharged many times. Primary batteries have high density and a lower self-discharge rate. Secondary (rechargeable) batteries have less energy than primary batteries, but can be recharged up to a thousand times depending on their chemistry

20、 and environment. Typically the first use of a rechargeable battery gives almost 4 hours of continuous operation in an application or robot.句中句中discarded意为意为“丢弃丢弃”。An Introduction to Robotics Technology (3) Power supplies There are literally hundreds of types and styles of batteries available for us

21、e in robots. Batteries are categorized by their chemistry and size, and rated by their voltage and capacity. The voltage of a battery is determined by the chemistry of the cell, and the capacity by both the chemistry and size. See Table 8.1 for battery size.Size NEDA IECDescriptionAAA 24ALR03smalles

22、t of the command sizes AA15ALR6most popular small battery, typically used in packs of 2 or 4 C14ALR14small flashlight battery, large toys D13ALR20largest common battery 9V1604A6L-R61rectangular with clip-on connector An Introduction to Robotics Technology (4) Electronic controlIn a robot, there are

23、two major hardware platforms: The mechanical platform of unregulated voltages, power and back-EMF (ElectroMotive Force) spikes, and the electronic platform of clean power and 5-volt signals. These two platforms need to be bridged in order for digital logic to control mechanical systems. The classica

24、l component for this is a bridge relay. A control signal generates a magnetic field in the relays coil that physically closes a switch. MOSFETs (Metallic Oxide Semiconductor Field Effect Transistors) for example, are highly efficient silicon switches, available in many sizes like the transistor that

25、 can operate as a solid state relay to control the mechanical systems.句中句中EMF意为意为“电动势电动势”，bridge relay意为意为“桥形继电器桥形继电器” , MOSFETs意为意为“金属氧化物半导体场效应晶体管金属氧化物半导体场效应晶体管 ”，solid state relay 意为意为“固态继电器固态继电器”。An Introduction to Robotics Technology (4) Electronic controlOn the other hand, larger size robots ma

26、y require a PMDC motor, in which the decrease of the value o the MOSFETs “on”, resistance, results in great increases in the heat dissipation of the chip, thereby significantly reducing the chips heat temperature Junction temperatures within the MOSFET and the coefficients of conduction of the MOSFE

27、T package and heat sink are other important characteristics of PMDC motors.译为：另一方面，大尺寸的机器人可能需要一个永磁直流电机，译为：另一方面，大尺寸的机器人可能需要一个永磁直流电机，其中金属氧化物半导体场效应晶体管的通态电阻的降低，会极其中金属氧化物半导体场效应晶体管的通态电阻的降低，会极大地增加芯片的热损失，从而大大地降低芯片的温度。大地增加芯片的热损失，从而大大地降低芯片的温度。An Introduction to Robotics Technology (4) Electronic controlThere

28、are two broad families of transistors: Bipolar J unction Transistors (BJT) and Field-Effect Transistors (FET). In BJT devices, a small current flow at the base moderates a much larger current between the emitter and collector. In FET devices, the presence of an electrical field at the gate moderates

29、 the flow between the source and drain.句中句中BJT意为意为“双极结晶体管双极结晶体管”, FET意为意为“场效应晶体管场效应晶体管 ”， emitter and collector意为发射极和接收极，意为发射极和接收极，source and drain 意为源极和漏极。意为源极和漏极。An Introduction to Robotics Technology (5) Sensors Robots react according to a basic temporal measurement, requiring different kinds of

30、sensors.In most systems a sense of time is built-in through the circuits and programming. For this to be productive in practice, a robot has to have perceptual hardware and software, which updates quickly. Regardless of sensor hardware or software, sensing and sensors can be thought of as interactin

31、g with external events (in other words, the outside world). The sensor measures some attribute of the world. A sensor receives energy and transmits a signal to a display or computer. Sensors use transducers to change the input signal (sound, light, pressure, temperature etc.) into an analog or digit

32、al form capable of being used by a robot.句中句中perceptual意为意为“感知的感知的”，transducers意为意为“换能器换能器”。An Introduction to Robotics Technology (5) Sensors Logical sensors: One powerful abstraction of a sensor is a logical sensor, which is a unit of sensing or module that supplies a particular percept. It consis

33、ts of the signal processing, from the physical sensor, and the software processing needed to extract the percept.Proprioceptive sensors: Proprioception is dead reckoning, where the robot measures a signal originating within itself.Proximity sensors: A proximity sensor measures the relative distance

34、between the sensor and objects in the environment.句中句中Proprioceptive意为意为“本体感受的本体感受的”，dead reckoning 意意为为“推测推测”，proximity sensor意为意为“接近传感器接近传感器”。An Introduction to Robotics Technology (5) Sensors InfraRed (IR) sensors: Another type of active proximity sensor is an infrared sensor. It emits near-infra

35、red energy and measures whether any significant amount of the IR light is returned.Bump and feeler sensors: Another popular class of robotic sensing is tactile or touch-based, done with a bump and feeler sensor. Feelers or whiskers are constructed from sturdy wires. A bump sensor is usually a protru

36、ding ring around the robot consisting of two layers.句中句中Bump and feeler sensors意为意为“凹凸触角传感器凹凸触角传感器”， tactile意为意为“触觉的触觉的”，whiskers意为意为“触须触须”，sturdy意为意为“坚固的坚固的”，protruding ring意为意为“凸圈凸圈”。An Introduction to Robotics Technology 2. Microcontroller systemsMicrocontrollers (MCUs) are intelligent electronic

37、 devices used inside robots. They deliver functions similar to those performed by a microprocessor (Central Processing Unit, or CPU) inside a personal computer. MCUs are slower and can address less memory than CPUs, but are designed for real-world control problems. One of the major differences betwe

38、en CPUs and MCUS is the number of external components needed to operate them. MCUs can often run with zero external part, and typically need only an external crystal or oscillator.句中句中crystal or oscillator意为意为“液晶显示屏液晶显示屏”An Introduction to Robotics Technology 2. Microcontroller systemsThere are four

39、 basic aspects of a microcontroller: speed, size, memory, and other. Speed is designated in clock cycles, and is usually measured in millions of cycles per second (Mega Hertz, MHz). The use of the cycles varies in different MCUs, affecting the usable speed of the processor. Size specifies the number

40、 of bits of information the MCU can process in one step-the size of its natural cluster of information. MCUs come in 4-, 8-, 16-, and 32-bits, with 8-bit MCUs being the most common size. MCUs count most of their ROM in thousands of bytes (KB) and RAM (Random Access Memory) in single bytes. Many MCUs

41、 use the Harvard architecture，in which the program is kept in one section of memory (usually the internal or external SRAM). This in turn allows the processor to access the separate memories more efficiently.句中句中Harvard architecture意为意为“哈佛结构哈佛结构”。An Introduction to Robotics Technology 2. Microcontro

42、ller systemsThe fourth aspect of microcontrollers, referred to as “other”, includes features such as a dedicated input device that often (but not always) has a small LED or LCD display for output. A microcontroller also takes input from the device and controls it by sending signals to different comp

43、onents in the device. Also the program counter keeps track of which command is to be executed by the microcontroller.An Introduction to Robotics Technology 2. Microcontroller systemsR/C Servos: Servomotors, used in radio-controlled models (cars, planes, etc.) are useful in many kinds of smaller robo

44、ts, because they are compact and quite inexpensive. The servomotors themselves have built-in motor, gearbox, position-feedback mechanisms and controlling electronics. Standard radio control servomotors which are used in model airplanes, cars and boats are useful for making arms, legs and other mecha

45、nical appendages which move back and forth rather than rotating in circles.句中句中appendages意为意为“附件附件”。An Introduction to Robotics Technology 2. Microcontroller systemsPneumatics: Pneumatics is the name for fluid power used in a large number of commercial robots. Pneumatics is also used in a variety of

46、 anthropomorphic systems that fall under the category of fluid power. A better known branch of fluid power is hydraulics. Visit the pneumatics website for additional information.An Introduction to Robotics Technology 3. Summary The field of robotics has created a large class of robots with basic phy

47、sical and navigational competencies. At the same time, society has begun to move towards incorporating robots into everyday life, from entertainment to health care. Moreover, robots could free a large number of people from hazardous situations, essentially allowing them to be used as replacements fo

48、r human beings. Many of the applications being pursued by AI robotics researchers are already fulfilling that potential. 句中句中basic physical and navigational competencies意为意为“基本基本机体和导航能力机体和导航能力”An Introduction to Robotics Technology 3. Summary In addition, robots can be used for more commonplace task

49、s such as janitorial work. Whereas robots were initially developed for dirty, dull, and dangerous applications, they are now being considered as personal assistants. Regardless of application, robot will require more rather than less intelligence, and will thereby have a significant impact on our so

50、ciety in the future as technology expands to new horizons.句中句中janitorial work意为意为“看门工作看门工作”， dirty, dull, and dangerous 意为意为“在脏的工作环境、无趣的、有危险的在脏的工作环境、无趣的、有危险的”。Machine Vision in Brief 1. What is Machine Vision? “Machine Vision (MV)” is a field of study and technology whose goal is endow machines with

51、 the ability to perceive selective aspects of the world using visual means.This sounds like a circular definition. One can easily get lost in a particular concept or technology when trying to define machine Vision. Perhaps its best to start with a more ostensible definition, then. Those of us fortun

52、ate enough to have functional eyes have an incredible ability to perceive and understand the world through them. Engineers have long sought to endow machines with this capability. 句中句中ostensible意为意为“表面的表面的”。Machine Vision in Brief 1. What is Machine Vision? It is easy to assume that this just means

53、duplicating the mechanisms people use in machines, but thats not all there is to it. Some techniques involve projecting and reflecting laser beams off distant targets, for example, which is very different from how you and I work. Some systems can read and understand information in bar codes or other

54、 special constructs that are difficult for humans to deal with.句中句中bar codes意为意为“条形码条形码”。Machine Vision in Brief 1. What is Machine Vision? Most importantly, few techniques being researched or in use today really resemble the awesome complexity and flexibility available to humans. MV researchers hav

55、e their own bag of tricks. It may be that some day, they bring all those tricks together and find they can make machines “see” as well as or even better than humans do.句中句中tricks意为意为“技巧、技艺技巧、技艺”。Machine Vision in Brief 1. What is Machine Vision? All practical machine vision systems in use today exis

56、t for their own specific purposes. Some are used to ensure that parts coming off assembly lines are manufactured correctly. Some are used to detect the 1ines in a road for the benefit of cars that drive themselves. Though some interested parties claim otherwise, there are no general purpose vision s

57、ystems, either in laboratories or on the market.句中句中assembly lines意为意为“组装生产线组装生产线”。Machine Vision in Brief 1. What is Machine Vision? If it sounds like its difficult to define machine vision, dont fret. The point is that the field of machine vision is not simply interested duplicating human vision.

58、What is essential is the basic goal visual perception, i.e., the ability to “understand” the world visually, sufficiently for moving about in and interacting with a complex, ever-changing world and discerning information in the environment. Figure 8.6 shows facial measures used in a biometrics visio

59、n system.句中句中fret意为意为“焦急焦急”。Machine Vision in Brief 2. General-Purpose Vision As mentioned above, all practical machine vision end products available now are for specific purposes.Human vision is general purpose. In our everyday experiences, we see a plenty of panoply things in all sorts of lighting

60、 conditions. We are able to operate well in almost any circumstance in which theres even a modest amount of light entering our eyes and which isnt damaging them.Merely being able to see light is nearly useless, though. The best video cameras today are still just recording or transmission devices; th