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1、<p><b>  Robot</b></p><p>  C. M. Shruthi , A. P. Sudheer , M. L. Joy</p><p>  Abstract After more than 40 years of development, since its first appearance till now, the robot h

2、as already been widely applied in every industrial fields, and it has become the important standard of industry modernization.</p><p>  Robotics is the comprehensive technologies that combine with mechanics,

3、 electronics, informatics and automatic control theory. The level of the robotic technology has already been regarded as the standard of weighing a national modern electronic-mechanical manufacturing technology.</p>

4、;<p>  Over the past two decades, the robot has been introduced into industry to perform many monotonous and often unsafe operations. Because robots can perform certain basic more quickly and accurately than human

5、s, they are being increasingly used in various manufacturing industries.</p><p>  With the maturation and broad application of net technology, the remote control technology of robot based on net becomes more

6、 and more popular in modern society. It employs the net resources in modern society which are already three to implement the operatio of robot over distance. It also creates many of new fields, such as remote experiment,

7、 remote surgery, and remote amusement. What's more, in industry, it can have a beneficial impact upon the conversion of manufacturing means.</p><p>  The key words are reprogrammable and multipurpose bec

8、ause most single-purpose machines do not meet these two requirements. The term “reprogrammable” implies two things: The robot operates according to a written program, and this program can be rewritten to accommodate a va

9、riety of manufacturing tasks. The term “multipurpose” means that the robot can perform many different functions, depending on the program and tooling currently in use.</p><p>  Developed from actuating mecha

10、nism, industrial robot can imitation some actions and functions of human being, which can be used to moving all kinds of material components tools and so on, executing mission by execuatable program multifunction manipul

11、ator. It is extensive used in industry and agriculture production, astronavigation and military engineering.</p><p>  During the practical application of the industrial robot, the working efficiency and qual

12、ity are important index of weighing the performance of the robot. It becomes key problems which need solving badly to raise the working efficiencies and reduce errors of industrial robot in operating actually. Time-optim

13、al trajectory planning of robot is that optimize the path of robot according to performance guideline of minimum time of robot under all kinds of physical constraints, which can make the moti</p><p>  Due to

14、 its important role in theory and application, the motion planning of industrial robot has been given enough attention by researchers in the world. Many researchers have been investigated on the path planning for various

15、 objectives such as minimum time, minimum energy, and obstacle avoidance.</p><p>  The basic terminology of robotic systems is introduced in the following:</p><p>  A robot is a reprogrammable,

16、multifunctional manipulator designed to move parts, materials, tools, or special devices through variable programmed motions for the performance of a variety of different task. This basic definition leads to other defini

17、tions, presented in the following paragraphs that give a complete picture of a robotic system.</p><p>  Preprogrammed locations are paths that the robot must follow to accomplish work. At some of these locat

18、ions, the robot will stop and perform some operation, such as assembly of parts, spray painting, or welding. These preprogrammed locations are stored in the robot’s memory and are recalled later for continuous operation.

19、 Furthermore, these preprogrammed locations, as well as other programming feature, an industrial robot is very much like a computer, where data can be stored and later recalled </p><p>  The tooling and grip

20、pers are not part of the robotic system itself: rather, they are attachments that fit on the end of the robot’s arm. These attachments connected to the end of the robot’s arm allow the robot to lift parts, spot-weld, pai

21、nt, arc-well, drill, deburr, and do a variety of tasks, depending on what is required of the robot.</p><p>  The robotic system can also control the work cell of the operating robot. The work cell of the rob

22、ot is the total environment in which the robot must perform its task. Included within this cell may be the controller, the robot manipulator, a work table, safety features, or a conveyor. All the equipment that is requir

23、ed in order for the robot to do its job is included in the work cell. In addition, signals from outside devices can communicate with the robot in order to tell the robot when it shou</p><p>  The robotic sys

24、tem has three basic components: the manipulator, the controller, and the power source. </p><p>  Manipulator</p><p>  The manipulator, which dose the physical work of the robotic system, consist

25、s of two sections: the mechanical section and the attached appendage. The manipulator also has a base to which the appendages are attached.</p><p>  The base of the manipulator is usually fixed to the floor

26、of the work area. Sometimes, though, the base may be movable. In this case, the base is attached to either a rail or a track, allowing the manipulator to be moved from one location to anther.</p><p>  As men

27、tioned previously, the appendage extends from the base of the robot. The appendage is the arm of the robot. It can be either a straight, movable arm or a jointed arm. The jointed arm is also known as an articulated arm.&

28、lt;/p><p>  The appendages of the robot manipulator give the manipulator its various axes of motion. These axes are attached to a fixed base, which, in turn, is secured to a mounting. This mounting ensures that

29、 the manipulator will remain in one location.</p><p>  At the end of the arm, a wrist is connected. The wrist is made up of additional axes and a wrist flange. The wrist flange allows the robot user to conne

30、ct different tooling to the wrist for different jobs.</p><p>  The manipulator’s axes allow it to perform work within a certain area. This area is called the work cell of the robot, and its size corresponds

31、to the size of the manipulator. As the robot’s physical size increases, the size of the work cell must also increase.</p><p>  The movement of the manipulator is controlled by actuators, or drive system. The

32、 actuator, or drive system, allows the various axes to move within the work cell. The drive system can use electric, hydraulic, or pneumatic power. The energy developed by the drive system is converted to mechanical powe

33、r by various mechanical drive systems. The drive systems are coupled through mechanical linkages. These linkages, in turn, drive the different axes of the robot. The mechanical linkages may be compose</p><p>

34、;  Controller</p><p>  The controller in the robotic system is the heart of the operation. The controller stores preprogrammed information for later recall, controls peripheral devices, and communicates with

35、 computers within the plant for constant updates in production.</p><p>  The controller is used to control the robot manipulator’s movements as well as to control peripheral components within the work cell.

36、The user can program the movements of the manipulator into the controller through the use of a hand-held teach pendant. This information is stored in the memory of the controller for later recall. The controller stores a

37、ll program data for the robotic system. It can store several different programs, and any of these programs can be edited.</p><p>  The controller is also required to communicate with peripheral equipment wit

38、hin the work cell. For example, the controller has an input line that identifies when a machining operation is completed. When the machine cycle is completed, the input line turns on, telling the controller to position t

39、he manipulator so that it can pick up the finished part. Then, a new part is picked up by the manipulator and placed into the machine. Next, the controller signals the machine to start operation.</p><p>  Th

40、e controller can be made from mechanically operated drums that step through a sequence of events. This type of controller operates with a very simple robotic system. The controllers found on the majority of robotic syste

41、ms are more complex devices and represent state-of-the-art electronics. This is, they are microprocessor-operated. These microprocessors are either 8-bit, 16-bit, or 32-bit processors. This power allows the controller to

42、 the very flexible in its operation.</p><p>  The controller can send electric signals over communication lines that allow it to talk with the various axes of the manipulator. This two-way communication betw

43、een the robot manipulator and the controller maintains a constant update of the location and the operation of the system. The controller also controls any tooling placed on the end of the robot’s wrist.</p><p&

44、gt;  The controller also has the job of communicating with the different plant computers. The communication link establishes the robot as part of a computer-assisted manufacturing (CAM) system.</p><p>  As t

45、he basic definition stated, the robot is a reprogrammable, multifunctional manipulator. Therefore, the controller must contain some type of memory storage. The microprocessor-based systems operate in conjunction with sol

46、id-state memory devices. These memory devices may be magnetic bubbles, random-access memory, floppy disks, or magnetic tape. Each memory storage device stores program information for later recall or for editing.</p>

47、;<p>  Power supply</p><p>  The power supply is the unit that supplies power to the controller and the manipulator. Two types of power are delivered to the robotic system. One type of power is the AC

48、 power for operation of the controller. The other type of power is used for driving the various axes of the manipulator. For example, if the robot manipulator is controlled by hydraulic or pneumatic drives, control signa

49、ls are sent to these devices, causing motion of the robot.</p><p>  For each robotic system, power is required to operate the manipulator. This power can be developed from either a hydraulic power source, a

50、pneumatic power source, or an electric power source. These power sources are part of the total components of the robotic work cell.</p><p>  Classification of Robots</p><p>  Industrial robots v

51、ary widely in size, shape, number of axes, degrees of freedom, and design configuration. Each factor influences the dimensions of the robot’s working envelope or the volume of space within which it can move and perform i

52、ts designated task. A broader classification of robots can been described as blew.</p><p>  Fixed and Variable-Sequence Robots. The fixed-sequence robot (also called a pick-and place robot) is programmed for

53、 a specific sequence of operations. Its movements are from point to point, and the cycle is repeated continuously. The variable-sequence robot can be programmed for a specific sequence of operations but can be reprogramm

54、ed to perform another sequence of operation.</p><p>  Playback Robot. An operator leads or walks the playback robot and its end effector through the desired path. The robot memorizes and records the path and

55、 sequence of motions and can repeat them continually without any further action or guidance by the operator.</p><p>  Numerically Controlled Robot. The numerically controlled robot is programmed and operated

56、 much like a numerically controlled machine. The robot is servo-controlled by digital data, and its sequence of movements can be changed with relative ease.</p><p>  Intelligent Robot. The intellingent robot

57、 is capable of performing some of the functions and tasks carried out by human beings. It is equipped with a variety of sensors with visual and tactile capabilities.</p><p>  Robot Applications</p>&l

58、t;p>  The robot is a very special type of production tool; as a result, the applications in which robots are used are quite broad. These applications can be grouped into three categories: material processing, material

59、 handling and assembly.</p><p>  In material processing, robots use to process the raw material. For example, the robot tools could include a drill and the robot would be able to perform drilling operations

60、on raw material.</p><p>  Material handling consists of the loading, unloading, and transferring of workpieces in manufacturing facilities. These operations can be performed reliably and repeatedly with robo

61、ts, thereby improving quality and reducing scrap losses.</p><p>  Assembly is another large application area for using robotics. An automatic assembly system can incorporate automatic testing, robot automati

62、on and mechanical handling for reducing labor costs, increasing output and eliminating manual handling concerns.</p><p>  Hydraulic System</p><p>  There are only three basic methods of transmit

63、ting power: electrical, mechanical, and fluid power. Most applications actually use a combination of the three methods to obtain the most efficient overall system. To properly determine which principle method to use, it

64、is important to know the salient features of each type. For example, fluid systems can transmit power more economically over greater distances than can mechanical type. However, fluid systems are restricted to shorter di

65、stances than a</p><p>  Hydraulic power transmission systems are concerned with the generation, modulation, and control of pressure and flow, and in general such systems include:</p><p>  Pumps

66、which convert available power from the prime mover to hydraulic power at the actuator.</p><p>  Valves which control the direction of pump-flow, the level of power produced, and the amount of fluid-flow to t

67、he actuators. The power level is determined by controlling both the flow and pressure level.</p><p>  Actuators which convert hydraulic power to usable mechanical power output at the point required.</p>

68、;<p>  The medium, which is a liquid, provides rigid transmission and control as well as lubrication of components, sealing in valves, and cooling of the system.</p><p>  Connectors which link the var

69、ious system components, provide power conductors for the fluid under pressure, and fluid flow return to tank(reservoir).</p><p>  Fluid storage and conditioning equipment which ensure sufficient quality and

70、quantity as well as cooling of the fluid..</p><p>  Hydraulic systems are used in industrial applications such as stamping presses, steel mills, and general manufacturing, agricultural machines, mining indus

71、try, aviation, space technology, deep-sea exploration, transportation, marine technology, and offshore gas and petroleum exploration. In short, very few people get through a day of their lives without somehow benefiting

72、from the technology of hydraulics.</p><p>  The secret of hydraulic system’s success and widespread use is its versatility and manageability. Fluid power is not hindered by the geometry of the machine as is

73、the case in mechanical systems. Also, power can be transmitted in almost limitless quantities because fluid systems are not so limited by the physical limitations of materials as are the electrical systems. For example,

74、the performance of an electromagnet is limited by the saturation limit of steel. On the other hand, the power limit o</p><p>  Industry is going to depend more and more on automation in order to increase pro

75、ductivity. This includes remote and direct control of production operations, manufacturing processes, and materials handling. Fluid power is the muscle of automation because of advantages in the following four major cat

76、egories.</p><p>  Ease and accuracy of control. By the use of simple levers and push buttons, the operator of a fluid power system can readily start, stop, speed up or slow down, and position forces which pr

77、ovide any desired horsepower with tolerances as precise as one ten-thousandth of an inch. Fig. shows a fluid power system which allows an aircraft pilot to raise and lower his landing gear. When the pilot moves a small c

78、ontrol valve in one direction, oil under pressure flows to one end of the cylinder to lower</p><p>  Multiplication of force. A fluid power system (without using cumbersome gears, pulleys, and levers) can mu

79、ltiply forces simply and efficiently from a fraction of an ounce to several hundred tons of output.</p><p>  Constant force or torque. Only fluid power systems are capable of providing constant force or torq

80、ue regardless of speed changes. This is accomplished whether the work output moves a few inches per hour, several hundred inches per minute, a few revolutions per hour, or thousands of revolutions per minute.</p>

81、<p>  Simplicity, safety, economy. In general, fluid power systems use fewer moving parts than comparable mechanical or electrical systems. Thus, they are simpler to maintain and operate. This, in turn, maximizes sa

82、fety, compactness, and reliability. For example, a new power steering control designed has made all other kinds of power systems obsolete on many off-highway vehicles. The steering unit consists of a manually operated di

83、rectional control valve and meter in a single body. Because the steerin</p><p>  Additional benefits of fluid power systems include instantly reversible motion, automatic protection against overloads, and in

84、finitely variable speed control. Fluid power systems also have the highest horsepower per weight ratio of any known power source. In spite of all these highly desirable features of fluid power, it is not a panacea for al

85、l power transmission problems. Hydraulic systems also have some drawbacks. Hydraulic oils are messy, and leakage is impossible to completely eliminate. A</p><p>  Pneumatic System</p><p>  Pneu

86、matic system use pressurized gases to transmit and control power. As the name implies, pneumatic systems typically use air (rather than some other gas ) as the fluid medium because air is a safe, low-cost, and readily av

87、ailable fluid. It is particularly safe in environments where an electrical spark could ignite leaks from system components.</p><p>  In pneumatic systems, compressors are used to compress and supply the nece

88、ssary quantities of air. Compressors are typically of the piston, vane or screw type. Basically a compressor increases the pressure of a gas by reducing its volume as described by the perfect gas laws. Pneumatic systems

89、normally use a large centralized air compressor which is considered to be an infinite air source similar to an electrical system where you merely plug into an electrical outlet for electricity. In this way,</p>&l

90、t;p>  Free air from the atmosphere contains varying amounts of moisture. This moisture can be harmful in that it can wash away lubricants and thus cause excessive wear and corrosion. Hence, in some applications, air d

91、riers are needed to remove this undesirable moisture. Since pneumatic systems exhaust directly into the atmosphere , they are capable of generating excessive noise. Therefore, mufflers are mounted on exhaust ports of air

92、 valves and actuators to reduce noise and prevent operating personnel</p><p>  There are several reasons for considering the use of pneumatic systems instead of hydraulic systems. Liquids exhibit greater ine

93、rtia than do gases. Therefore, in hydraulic systems the weight of oil is a potential problem when accelerating and decelerating and decelerating actuators and when suddenly opening and closing valves. Due to Newton’s law

94、 of motion ( force equals mass multiplied by acceleration ), the force required to accelerate oil is many times greater than that required to accelerate</p><p>  However, because of the compressibility of ai

95、r, it is impossible to obtain precise controlled actuator velocities with pneumatic systems. Also, precise positioning control is not obtainable. While pneumatic pressures are quite low due to compressor design limitatio

96、ns ( less than 250 psi ), hydraulic pressures can be as high as 10,000 psi. Thus, hydraulics can be high-power systems, whereas pneumatics are confined to low-power applications. Industrial applications of pneumatic syst

97、ems are growing</p><p><b>  工業(yè)機(jī)器人</b></p><p>  C. M. Shruthi , A. P. Sudheer , M. L. Joy</p><p>  摘要:機(jī)器人自問(wèn)世以來(lái)到現(xiàn)在,經(jīng)過(guò)了40多年的發(fā)展,已被廣泛應(yīng)用于各個(gè)工業(yè)領(lǐng)域,已成為工業(yè)現(xiàn)代化的重要標(biāo)志。機(jī)器人技術(shù)是一門(mén)機(jī)械、電子、自動(dòng)控

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