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附录A 英文文献
operations research techniques in industrial engineering
1.Introduction of Industrial Engineering
Industrial Engineering (often now supplemented as "Industrial & Systems Engineering" or "Industrial & Operations Engineering") is a branch of engineering dealing with optimizing complex processes or systems. It is concerned with the development, improvement, implementation and evaluation of integrated systems of people, money, knowledge, information, equipment, energy, materials and/or processes. It also deals with designing new product prototypes more efficiently and more effectively. Industrial engineering draws upon the principles and methods of engineering analysis and synthesis, as well as the mathematical, physical and social sciences together with the principles and methods of engineering design to specify, predict, and evaluate the results to be obtained from such systems or processes. Its underlying concepts overlap considerably with certain busines-oriented disciplines such as Operations Management, but the engineering side tends to greater emphasize extensive mathematical proficiency and utilization of quantitative methods.
While the term originally applied to manufacturing, nowadays the term "industrial" in industrial engineering can be somewhat misleading (leading to the typical extensions noted above). It has grown to encompass any methodical or quantitative approach to optimizing how a process, system, or organization operates. In fact, the primary U.S. professional organization for Industrial Engineers, the Institute of Industrial Engineers (IIE) has been considering changing its name to something broader (such as the Institute of Industrial & Systems Engineers), although the latest vote among membership deemed this unnecessary for the time being. The various topics of concern to industrial engineers include management science, financial engineering, engineering management, supply chain management, process engineering, operations research, systems engineering, ergonomics, cost and value engineering, quality engineering, facilities planning, and the engineering design process. Traditionally, a major aspect of industrial engineering was planning the layouts of factories and designing assembly lines and other manufacturing paradigms. And now, in so-called lean manufacturing systems, industrial engineers work to eliminate wastes of time, money, materials, energy, and other resources.
All engineers work at planning, designing, implementing and controlling the systems that represent the way people use technology. The systems that are the subject of Industrial Engineering design are broad and are characterized by a need to integrate both the physical and decision making capabilities of humans together with all other aspects of the system design. Problems range from the design of a work method and work station, to the design of a factory layout and methods of controlling the flow of materials on the factory floor, to the design of an overall corporate plan involving materials procurement, production, inventory and distribution. The idea of a factory is also extended to include health care systems, municipal systems, transportation systems; in fact all the systems that are essential to the functioning of modern society. Systems that facilitate effective decision making and implementation in areas such as scheduling, inventory, and quality control are typical of industrial engineering.
Examples of where industrial engineering might be used include designing an assembly workstation, strategizing for various operational logistics, consulting as an efficiency expert, developing a new financial algorithm or loan system for a bank, streamlining operation and emergency room location or usage in a hospital, planning complex distribution schemes for materials or products (referred to as Supply Chain Management), and shortening lines (or queues) at a bank, hospital, or a theme park. Industrial engineers typically use computer simulation (especially discrete event simulation), along with extensive mathematical tools and modeling and computational methods for system analysis, evaluation, and optimization
2.Industrial Engineering in the enterprise application
Guangzhou Honda Automobile Co., Ltd. (Guangzhou Honda) in 2006 established a second plant, part of the stamping into a fully automated stamping production line, mainly the appearance of the production of Accord car cover. In order to reduce the equipment cost into the production line this time a split way unit, namely the procurement of small Oyabe Japan unstacking of cleaning and feeding device, 2 machine presses, Jinan, Shanghai, the company's handling robot ABB; Then, to ABB's entire line of integrated solutions in collaboration with manufacturers to integrate the entire line, the establishment of a production line of automatic stamping (see Figure 1). Modular form of procurement through full use of different manufacturers in their respective strengths in the field, combine their advanced technology, in the procurement of Guangzhou Honda to achieve a good cost-cutting effect.
Figure 1 The second plant of Guangzhou Honda stamping production line Post-production problems
Since this is the first time all three companies to cooperate, and Guangzhou Honda is the first time the press handling robots into automated production lines, production lines in the design, manufacture stage, the equipment manufacturers do not take sufficient account of the production rate of the production line problem. Especially in the production line early in the production line to optimize the production rate, we have a lot of difficulties, specifically as follows:
1. Equipment and control devices, there are many logical inconsistencies, the result is a direct production line resulted in slow rhythms, such as: in January 2007 the average production line needs a parts 8.1s;
2. New factories, equipment used in the past, different, technology personnel need to take the time to grasp the characteristics of a variety of devices, and then the beat will go to consider the optimal production program;
3. The flexible robot is very large, the early production operators are not familiar with, not meet, there is no sense of optimization, which takes time to master the ability to optimize;
4. Between different manufacturers equipment, lack of accuracy of the signal chain, increase productivity and also increase the speed of the equipment of the probability of collision, it is difficult to find equipment productivity and the balance between security;
5. All equipment is only used between each other to optimize the signal chain, there is no production line speed control mode and a dedicated controller;
6. There is no synchronization of the system into the robot, the hardware is optimized to increase the degree of difficulty, and bound in a certain range of production rhythms.
Elements of the impact of production rate
In 2007, the production line technicians, operators of a continuous effort to improve efficiency and optimize production line operations, in the field of application of the idea of continuous improvement to reduce the value of parts produced by CT. After continuous efforts, we sum up a production line to optimize an effective way to beat. January 2008 No. 8 on behalf of Accord started production at the same time; we started on the optimization of stamping production line work. We only took a month to optimize the production line to the ideal state, in February 2008, the average production line parts of a time to 6.9s.
At this point, we will talk about the speed associated with the production elements and production lines to optimize the production method of the beat.
Punching robots in automated production lines, there are two speeds associated with the production of very important elements, namely: the speed of the equipment and the movement of motor coordination.
1. Movement speed
In practice, we found that when the equipment is running at maximum speed, and each punch presses simultaneously, each time moving the robot simultaneously, the fastest production line. The speed of the equipment, the unstacking unit and press the speed of change is not normally; and robot velocity flexible adjustment is very large, the impact of the production line to become a major factor in speed.
Robots and robot velocity is closely related to the movement characteristics, in addition to the actual velocity value and set the relationship between size, but also with the movement position in the process of change and movement are related. The characteristics of the robot moves as follows:
(1) changes in posture during the movement the less the faster movement. The premise that security is guaranteed, the as shown in Figure 2, the second paragraph of the first paragraph of the track and the track is set to approximate the planar motion (trajectory of the paragraphs of the Z coordinates of each point or less the same data), thereby reducing the process of robot movement changes in posture.Figure 2 in the first paragraph of the robot trajectory and the trajectory is set to close in the second paragraph of the planar motion
(2) robot velocity is characterized by movement between the two points (see Figure 3): MOVJ arc velocity> MOVL speed linear motion. MOVEJ when you select the command, the robot will automatically calculate the fastest movement trajectory arc.
Figure 3 between the two campaigns, the robot velocity MOVJ arc> MOVL speed linear motion
Understanding of the characteristics of the robot moves, it can be standardized in all parts of the track. Into new parts, reproduction parts similar trajectory ago, so after a simple change can be an ideal trajectory. Done after this step, you can move a single robot to the fastest speed to meet the elements of the first condition.
2. Of motor coordination
How to each the largest in their respective sport combines the speed of the equipment together, form a fast-paced production line? That is, how to regulate the coordination of action between devices as well?
First of all, analyze what is the ideal stamping production line to optimize the state? Production line is ideal to optimize the state of the equipment to the maximum speed of their run to the shortest cycle time to complete a single action, every movement of the equipment is only one cycle of wait point; in the premise of security, the former one device to start as soon as possible the next piece of equipment. Standing on the point of view of the entire line, the robot can move to send synchronization, synchronization can be punching presses (see Figure 4). Robot is expected to start on the back end, the press started slider, and die almost collided with the robot; slider began to rise, the robot immediately into the reclaimer, and almost collided with the mold. That is, equipment to the maximum speed of their operation, start-up parameters between the settings to maximum, and to coordinated movement.
Figure 4 to achieve the robot to move to send the synchronization and the synchronization stamping presses Production line to optimize the production of the beat
In order to better analysis of the production line, we have the production line is divided into five units, to reduce production time for each part is to reduce the time for each unit of action. Unshackling unit as a result of the use of a 2-dimensional movement of the feed material in hand, the hand-feeding movements of the robot cycle time than the faster cycle time, hand-feeding unit is not a production line bottlenecks. Here, we will focus on the robot unit. Production line robot cell is the press and the press behind the robots, the action unit of time (see Figure 5) is the stamping presses, robotic cutting, feeding robot, the robot is expected to return to waiting for the next press time the whole process.
Figure 5 units of time T = t press stamping + t Robot Robot Cutting + t on + t the robot is expected to return to wait for the next feed point
Production line unit is the most important element, the first unit of the equipment will be coordinated action so that the action unit of time at least, the production line in order to further coordinated actions of the unit to optimize the effectiveness of the production line. How to make the unit arrived in motor coordination of the equipment unit will take at least it moves? There are three main methods:
1. To reduce the robot trajectory in the pick up point and the point of discharge from the Z direction (see Figure 6), to reduce the robot's stay in the press of time to allow the robot to leave the press as soon as possible, as well as related equipment to start the next move.
Figure 6 Trajectory of robot pick-up point and the discharge point of the distance between the Z direction
2. To speed up the robot is expected to start after the stamping presses
Optimization of parameters of the robot has a robot can be adjusted to the back after feeding with the interference from the point of value, thereby changes the speed stamping presses start. After the robot is expected to start on the fastest time stamping presses, when the robot started to feed back as soon as the end to start sending signals Press.
3. After stamping presses to speed up the cutting robot
There are two ways to speed up the presses after punching cutting robot, shown in Figure 7. First, to make tracks in the press around waitunload points; Second, press start to reduce the cutting angle of the robot.
Figure 7 points around waitunload first press, and then start to reduce the angle
Optimization of the production line must be met to the last state to enter the optimization problem of initial conditions. For example, in the stamping process to stop the production line cleaning mode, in this article on the experience into the production line to optimize the initial conditions of the state. If the production line in accordance with the clean mold from the press to stop start the automatic production line, the production line moves the beginning of each unit of time is different, each unit is similar to the action of time, can not enter the production line has been to optimize the way a good sync. At that time, had to take another way to make the production line has been optimized access to synchronize a good way. As shown in Figure 11, to resume, when the entire line of equipment to enter the state after the automatic stop machine for unstacking expected, unstacking units billet hand feeding suspended awaiting the point in waiting for materials, other equipment normal operation;
3.Concluding remarks
Optimization of the production line is very meaningful. Optimization of the production line after a substantial increase in operating efficiency, in the same period of time can produce more parts, thus reducing the cost of production parts and equipment cost. Particularly in the equipment of the vehicle into a relatively larger production line stamping plant, optimization is even more important.
Job opportunities for Industrial Engineers are both challenging and widely based. Former graduates are currently practicing Industrial Engineering in all types of work activity ranging from paper product manufacturing, to airlines, to utilities, to hospitals. Invariably, the work assigned is original in its nature demanding that the Industrial Engineer to be creative in applying his or her many abilities to achieve the best solution. Managers require such results if they are to keep their costs under control and improve the quality in this increasingly competitive world. This requirement will sustain the high demand for Industrial Engineers well into the future.
附录B 汉语翻译
工业工程的运用
1.工业工程的介绍
工业工程（通常现在补充为“工业及系统工程”或“工业及营运工程”）是优化处理复杂流程或系统工程的一部分。它关注的是发展，改进，实施和评估包括人员，成本，知识，信息，设备，能源，材料和/或流程为的一体的系统。它同时处理更高效、有效的设计新产品原型。工业工程利用分析和综合工程的原则和方法，以及数学，物理和社会科学的设计方法来确定，预测和评估从这样的系统或流程获得的结果。它的基本概念与某些面向业务原理相重叠，比如说营运管理等学科等，但在工程方面更倾向于强调宽广的数学能力和定量方法的使用。
虽然长期原本用于工作，现在在工业工程中所谓的“工业”可能有点错误的理解（导致典型扩展如上所述）。它已经发展到包括任何有有序的或定量方法的如何优化流程，系统或组织的运作。事实上，作为美国主要的工业工程师组织也就是工业工程师研究所（IIE）正考虑把它的名字更改得更广泛一些（如工业及系统工程师研究所），虽然各成员最新投票认为这暂时是不必要的。工业工程师关注的各种课题包括管理科学，金融工程，工程管理，供应链管理，工艺工程，运筹学，系统工程，人机工程，成本和价值工程，质量工程，办公室规划，工程设计过程。传统上，工业工程的主要方面是办公室的规划布局和设计组装线等制造模式。现在，在所谓的精益办公人员中，工业工程师的工作是消除时间，金钱，材料，能源和其他资源的浪费。
所有工程师在规划，设计，实施和控制系统领域的工作其实也就是代表了人们对技术的使用。该工业工程设计课题系统很广泛，是由一个需要整合包括有形决策系统的设计有包含所有其他方面系统的设计。问题的范围从一个工作方法和工作车站设计，到办公室里材料的布局和控制，以至于一个整体的企业，其中涉及材料采购，工作，库存和分配计划的设计。一个办公室的概念也扩大到包括卫生保健系统，市政系统，交通系统，实际上所有的系统对现代社会的运作来说是必不可少的。系统在这些领域诸如有效的决策、实施、调度和库存，质量控制是典型的工业工程。
工业工程在哪里被使用的例子包括设计一个包括装配工作站，为各种业务的工作效率谋划，咨询一个高效率专家，给银行金融开发新算法或贷款制度，简化操作，并在医院急诊室位置或使用，规划材料或产品（以下简称复杂的分配计划，以供应链管理），缩短在银行，医院，或主题公园的线路（或排队）。工业工程师通常使用的计算机模拟（特别是离散事件仿真），以及具有广泛的数学工具和系统建模和分析，评估计算方法和优化等。
2.工业工程在企业中的运用
广州本田汽车有限公司（简称广州本田）2006年建立了第二办公室，在冲压部分导入了一条全自动的冲压工作线，主要工作雅阁车的外观覆盖件。为了降低设备成本，导入这条工作线的时候采用了拆分单元的方式进行，分别采购了日本小矢部的拆垛清洗和上料装置、济南二机的压力机、上海ABB公司的搬运设备人；然后，以ABB公司的整线集成方案协同各厂家集成整线，建立了一条自动冲压工作线（见图1）。通过分单元采购形式，充分利用不同厂家在各自领域内的强项，揉合他们的先进技术，在采购中广州本田实现了很好的成本削减效果。
图1 广州本田第二办公室的冲压工作线
投产后遇到的问题
由于这三家公司是第一次合作，且广州本田也是第一次导入设备人搬运的冲压自动工作线，在工作线设计、制造阶段，各设备厂家没有充分考虑工作线的工作速率问题。特别是在工作线的投产初期，在工作线工作速度优化方面，我们遇到很多困难，具体表现为：
1. 设备与设备之间的控制逻辑存在很多不一致的地方，直接的结果就是导致工作线工作节拍慢，比如：2007年1月份工作线平均工作1个零件需要8.1s；
2. 全新的办公室，所使用的设备也不同以往，技术人员需要花时间来掌握各种设备的特点，然后才会再去考虑工作节拍的优化方案；
3. 设备人的柔性非常大，投产初期操作人员不熟悉、不适应，没有优化意识，需要时间才能掌握优化的本领；
4. 不同厂家设备之间的连锁信号缺乏准确性，提高工作速度的同时也增加了设备发生相互碰撞的概率，难以找到工作效率与设备安全之间的平衡点；
5. 各个设备之间只是用相互之间的连锁信号进行优化，没有整线控制工作速度的模式与专用控制器；
6. 没有导入设备人的同步系统，硬件上增加了优化的难度，并且在一定范围内约束了工作节拍。
影响工作速度的要素
2007年，工作线的技术人员、操作人员不断地为提高效率而进行工作线的优化作业，在现场中应用持续改善的思想降低零件工作的CT值。经过不断努力，我们总结出一套优化工作线工作节拍的有效方法。2008年1月第8代雅阁开始投产，与此同时，我们开始展开对冲压工作线的优化工作。我们只用了一个月的时间就把工作线优化到理想状态，2008年2月，工作线平均工作1个零件的时间缩短到6.9s。
在此，我们将谈谈与工作速度相关的要素和工作线优化工作节拍的方法。
冲压设备人自动工作线中，有两个与工作速度相关的非常重要的要素，即：各设备的动作速度和动作协调性。
1．动作速度
在实践中我们发现，当各设备以最大的速度运行，并且各台压力机同步冲压、各台设备人同步搬运的时候，工作线工作速度最快。对于各设备速度来说，拆垛单元和压力机的速度通常是不会变更的；而设备人运动速度调整的柔性非常大，成为影响工作线速度的主要因素。
设备人的运动速度与设备人的动作特征是有密切关系的，除其实际的运动速度与设定的数值大小有关系外，还与运动过程中的姿势变化和运动方式有关系。设备人动作的特点如下：
（1）运动过程中姿势变化越少运动速度越快。在保证安全的前提下，如图2所示，将第一段轨迹与第二段轨迹设置为近似的平面运动（各段轨迹中各点坐标的Z数据大致相同），从而减少设备人运动过程中姿势的变化。
图2 将设备人第一段轨迹与第二段轨迹设置为近似的平面运动
（2）设备人运动速度的特征是两个点之间的运动（见图3）：MOVJ弧线运动速度＞ MOVL直线运动速度。当选择MOVEJ命令，设备人会自动计算运动最快的弧线轨迹。
图3 在两个点之间的运动中，设备人的MOVJ弧线运动速度＞ MOVL直线运动速度
了解设备人动作的特点后，就可以将各个零件的轨迹标准化。导入新零件时，复制以前相似的零件轨迹，做简单的改动后就可以得到理想的轨迹。做了这一步后，就可以将单台设备人的搬运速度调到最快，满足要素中的第一个条件。
2. 动作协调性
如何将各台以各自最大运动速度的设备揉合在一起，组成一条工作节奏快的工作线？也就是，如何调节设备之间动作的协调性呢？
首先，分析一下什么是冲压工作线理想的优化状态？工作线理想的优化状态就是各设备以自己的最大速度运行，以最短时间完成单个动作循环，各设备的每个动作循环中只有一个等待点；在安全的前提下，前一台设备以最短时间启动下一台设备。站在整线的角度看，设备人能够同步搬送，压力机能够同步冲压（见图4）。设备人上完料开始后退时，压力机滑块开始启动，并且模具差点与设备人相撞；滑块开始上升时，设备人立即进入取料，并且差点与模具相撞。也就是，设备以自身最大的速度运行，相互之间的启动参数设置到最大值，并且能够协调一致运动。
图4 实现设备人的同步搬送和压力机的同步冲压
优化工作线的工作节拍
为了更好地对工作线进行分析，我们把工作线划分为5个单元，减少每个零件的工作时间就是要减少每个单元的动作时间。由于拆垛单元采用了2维运动的上料手送料，因此，上料手的动作循环时间比设备人的循环时间要快，上料手单元不是工作线的瓶颈。在此，我们将主要讨论设备人单元。工作线设备人单元是指压力机与压力机后面的设备人，单元的动作时间（见图5）是指压力机冲压、设备人下料、设备人上料、设备人回到压力机等待下料的整个过程的时间。
图5 单元时间T= t压力机冲压＋t设备人下料＋t设备人上料＋t设备人回到下料等待点
单元是工作线最重要的元素，首先将单元内的设备动作协调，使单元的动作时间最少，才能进一步使工作线的单元动作协调，达到工作线优化的效果。如何使单元的设备动作协调到达单元的动作时间最少呢？主要有三个方法：
1. 减少设备人轨迹中拾取点和放料点Z方向的距离（见图6），减少设备人在压力机里的停留时间，使设备人尽快离开压力机以及启动相关设备的下一个动作。
图6 设备人轨迹中拾取点和放料点Z方向之间的距离
2. 加快设备人上料后启动压力机冲压
设备人的优化参数里有一项可以调整设备人上料后往后退时与干涉点的距离数值，从而改变启动压力机冲压的快慢。设备人上料后启动压力机冲压最快的时机是，当设备人投料完毕开始后退时立即送出启动压力机信号。
3. 加快压力机冲压后设备人下料
有两个方法可以加快压力机冲压后设备人下料，如图7所示。一是使轨迹中的waitunload点靠近压力机；二是减少压力机启动设备人下料的角度。
图7 先将waitunload点靠近压力机，再减少启动角度
工作线优化到最后都要碰到进入最优化状态的初始条件问题。例如冲压工艺中的停止工作线抹模，在这条工作线上就遇到进入最优化状态的初始条件问题。如果工作线按照从停止抹模的压力机开始启动整线自动工作的话，工作线上各个单元的开始动作时间不一样，各个单元的动作时间相近，工作线不能进入已经优化好的同步方式。这时，唯有采用另外一种方式，才能使工作线进入已经优化好的同步方式。如图11所示，恢复时，当整线的设备都进入自动状态后，停止拆垛机供料，拆垛单元的上料手拿着坯料暂时停止，在上料等待点等待着，其他设备正常运转；
3.结束语
工作线的优化重要意义在于被优化后的工作线不仅大幅提高经营效率，而且在相同时间内可以工作更多的零部件，从而降低了工作零部件和设备成本。尤其是在车辆设备进入一个相对较大的工作线冲压办公室，优化显得更重要。
工业工程师的工作都充满挑战和广泛的基础。之前工业工程毕业生目前工作范围类型从纸工作企业办公室，航空公司，公用事业到医院。毫无例外，工作分配的本质要求就是工业工程师他或她拥有提出最佳解决方案的应用能力并且要有创造性。在这个日益竞争激烈的世界，管理人员要求控制成本同时提高质量，这就使对工业工程师的大量需求得以保持。
