机械专业英语论文
机械专业类英语文章阅读
机械专业类英语文章阅读篇一：机械专业英语作文1Mechanical engineeringEngineering Science in life are widely used, especially in mechanical engineering in the application of life is almost throughout life in all its aspects, to automobiles, aircraft, small electric fans, umbrella, all of these and related machinery. The project includes many subjects, but the mechanical engineering is one of the most important subjects, not only because of our life and itis closely related to, but with the progress of the times, people have to rely on mechanical engineering products, in automation today, machine instead of many this is the part of the human labor, improve the efficiency and save time.As a result of mechanical engineering in every aspect of life, therefore, as an engineer, be faced with a great many challenges, in addition to a solid with knowledge, but also keep pace with the times, familiar with the machinery and related software, can be very good use of software, and as a an engineer, we should try our best to design and produce and closely related to the life of the machine, and can in life play a real role, also have only such, we address and remission now social needs, therefore, the mechanical engineering in the future social development, will play the important role, especially China s case, the industry also is not very developed, machinery can be greater development space.Before the industrial revolution, machinery is mostly wood structure, wood made by hand by. The development of social economy,the demand for mechanical products. The bulk of the production increasing and precision processing technology progress, promote the mass production method ( interchangeability of parts production, professional division of labor and cooperation, water processinglines and assembly lines ) formation. Study of mechanical products in the manufacturing process, especially when used in the pollution of the environment and natural resources excessive consumption problems and their treatment measures. This is a modern mechanical engineering is an especially important task to grow with each passing day, andits importance.Application of mechanical products. This includes selection, ordering, acceptance, installation, adjustment, operation, maintenance, repair and transformation of the industrial use of machinery and complete sets of machinery and equipment, to ensurethat the mechanical products in the long-term use of reliability and economy.As a student, we are now the most important to learn professional knowledge, only in this way, can we later life and learning, to doits part.机械工程工程科学在生活中应用广泛，特别是机械工程在生活中的应用几乎就是遍布了生活中的各个方面，大到汽车、飞机，小到电风扇、雨伞，这些都和机械有关。
机械专业介绍英语作文
机械专业介绍英语作文The field of mechanical engineering is a diverse and dynamic discipline that encompasses the design, development, and implementation of a wide range of mechanical systems and devices. As a mechanical engineering student, I have had the opportunity to delve into the intricacies of this fascinating field, and I am excited to share my insights with you.At the core of mechanical engineering is the understanding and application of fundamental principles of physics, mathematics, and materials science. Mechanical engineers utilize these principles to create innovative solutions to complex problems, ranging from the design of simple machines to the development of advanced technologies that power our modern world.One of the key aspects of mechanical engineering is the design process. Mechanical engineers are responsible for conceptualizing, designing, and optimizing the performance of mechanical systems and components. This involves the use of computer-aided design (CAD) software, finite element analysis (FEA) tools, and other advanced modeling and simulation techniques to test and refine their designs.Another crucial aspect of mechanical engineering is the manufacturing and production of mechanical systems. Mechanical engineers work closely with manufacturing teams to ensure that their designs can be effectively and efficiently produced. This may involve the selection of appropriate materials, the implementation of advanced manufacturing processes, and the development of quality control measures to ensure the reliability and durability of the final product.In addition to design and manufacturing, mechanical engineers are also involved in the operation and maintenance of mechanical systems. They may be responsible for troubleshooting and repairing equipment, optimizing system performance, and developing preventive maintenance strategies to ensure the long-term reliability and efficiency of mechanical systems.One of the most exciting aspects of mechanical engineering is the opportunity to work on a wide range of applications and industries. Mechanical engineers can be found in sectors such as aerospace, automotive, energy, healthcare, and manufacturing, among others. This diversity of applications allows mechanical engineers to apply their skills and knowledge to solve complex problems and contribute to the advancement of technology and society.As a mechanical engineering student, I have had the privilege of exploring various specializations within the field. For example, I have delved into the design and analysis of thermal systems, such as heating, ventilation, and air conditioning (HVAC) systems, as well as the development of advanced energy conversion technologies, such as wind turbines and solar power systems.I have also had the opportunity to work on projects that involve the design and optimization of mechanical components, such as gears, bearings, and linkages. These projects have allowed me to apply my knowledge of materials science, solid mechanics, and dynamic systems to create innovative solutions that improve the performance and reliability of mechanical systems.In addition to technical skills, mechanical engineers must also possess strong problem-solving, critical thinking, and communication abilities. Effective collaboration with cross-functional teams, including engineers from other disciplines, as well as with clients and stakeholders, is essential for the successful completion of projects.As I look to the future, I am excited about the potential of mechanical engineering to continue driving technological advancements and contributing to the betterment of our world. With the rapid pace of innovation and the growing demand forsustainable and efficient solutions, I believe that mechanical engineering will play an increasingly important role in addressing global challenges, such as climate change, energy security, and healthcare.In conclusion, the field of mechanical engineering is a dynamic and multifaceted discipline that offers a wealth of opportunities for those who are passionate about technology, innovation, and problem-solving. As a mechanical engineering student, I am proud to be part of a profession that is at the forefront of shaping the future and improving the quality of life for people around the world.。
机械专业论文中英文
机械专业论文中英文Gearbox Noise —— Correlation with Transmission Error and Influence of Bearing Preload变速箱噪声——相关的传输错误和轴承预压的影响摘要ABSTRACTThe five appended papers all deal with gearbox noise and vibration. The first paper presents a review of previously published literature on gearbox noise and vibration.The second paper describes a test rig that was specially designed and built for noise testing of gears. Finite element analysis was used to predict the dynamic properties of the test rig, and experimental modal analysis of the gearbox housing was used to verify the theoretical predictions of natural frequencies.In the third paper, the influence of gear finishing method and gear deviations on gearbox noise is investigated in what is primarily an experimental study. Eleven test gear pairs were manufactured using three different finishing methods. Transmission error, which is considered to be an important excitation mechanism for gear noise, was measured as well as predicted. The test rig was used to measure gearbox noise and vibration for the different test gear pairs. The measured noise and vibration levels were compared with the predicted and measured transmission error. Most of the experimental results can be interpreted in terms of measured and predicted transmission error. However, it does not seem possible to identify one single parameter,such as measuredpeak-to-peak transmission error, that can be directly related to measured noise and vibration. The measurements also show that disassembly and reassembly of the gearbox with the same gear pair can change the levels of measured noise andvibration considerably.This finding indicates that other factors besides the gears affect gear noise.In the fourth paper, the influence of bearing endplay or preload on gearbox noise and vibration is investigated. Vibration measurements were carried out at torque levels of 140 Nm and 400Nm, with 0.15 mm and 0 mm bearing endplay, and with 0.15 mm bearing preload. The results show that the bearing endplay and preload influence the gearbox vibrations. With preloaded bearings, the vibrations increase at speeds over 2000 rpm and decrease at speeds below 2000 rpm, compared with bearings with endplay. Finite element simulations show the same tendencies as the measurements.The fifth paper describes how gearbox noise is reduced by optimizing the gear geometry for decreased transmission error. Robustness with respect to gear deviations and varying torque is considered in order to find a gear geometry giving low noise in an appropriate torque range despite deviations from the nominal geometry due to manufacturing tolerances. Static and dynamic transmission error, noise, and housing vibrations were measured. The correlation between dynamic transmission error, housing vibrations and noise was investigated in speed sweeps from 500 to 2500 rpm at constant torque. No correlation was found between dynamic transmission error and noise. Static loaded transmission error seems to be correlated with the ability of the gear pair to excite vibration in the gearbox dynamic system.论文描述了该试验台是专门设计和建造噪音齿轮测试。
机械类英语作文
Thirdly, the career prospects for mechanical engineers are vast and diverse. Graduates have the opportunity to work in industries such as automotive, aerospace, energy, and manufacturing. They are involved in the design and development of products, machinery, and systems, as well as the optimization of existing technologies. The demand for mechanical engineers is expected to grow in the coming years, particularly in emerging fields such as renewable energy and biomedical engineering.
机械工程专业的作文英语
As a high school student with a keen interest in engineering, Ive always been fascinated by the intricate workings of machines and the ingenious designs that make them function. This passion led me to a profound decision to pursue a career in Mechanical Engineering. The journey has been both challenging and rewarding, offering me a glimpse into a world where creativity meets functionality.My fascination with mechanical engineering began during a school project where we were tasked with building a simple pulley system. The concept was straightforward, yet the execution was anything but. I remember the initial frustration of not being able to get the pulley to function as expected, but with each failure, I learned something new about the principles of force and motion. This handson experience sparked a curiosity that propelled me to delve deeper into the field.The decision to pursue mechanical engineering was solidified during a summer internship at a local manufacturing plant. There, I witnessed firsthand the application of mechanical principles on a larger scale. The plant was a hive of activity, with machines whirring and workers meticulously assembling parts. It was a symphony of precision and efficiency, and I was captivated by the sheer scale of engineering feats that took place every day.During my time at the plant, I was fortunate enough to work alongside seasoned engineers who were more than willing to share their knowledge. They taught me about the importance of precision in engineering, how a slight miscalculation could lead to a chain reaction of errors. I learnedabout the various components of a machine, from the smallest gear to the largest engine block, and how each played a crucial role in the overall function of the system.One of the most enlightening experiences was when I was given the opportunity to participate in the design of a new machine part. It was a humbling experience to see my ideas come to life, and the sense of accomplishment was indescribable. It was during this project that I realized the true potential of mechanical engineering the ability to create solutions that can improve lives and drive progress.As I progressed through my high school years, I began to explore the various subfields within mechanical engineering. I was particularly drawn to robotics and automation, intrigued by the potential to create machines that could perform tasks with a level of precision and efficiency beyond human capabilities. I spent countless hours researching, building, and programming robots, each project teaching me more about the complexities of mechanical systems and the importance of problemsolving skills.The journey towards a career in mechanical engineering has not been without its challenges. The coursework has been demanding, requiring a strong foundation in mathematics, physics, and computer science. Yet, the challenges have only served to strengthen my resolve. Ive learned to embrace the complexities of the field, to find joy in solving complex problems, and to appreciate the beauty of welldesigned machinery.Looking ahead, I am excited about the prospect of attending university and furthering my education in mechanical engineering. I am eager to explore new technologies, to learn from experts in the field, and to contribute to the advancement of mechanical engineering. Whether its designing more efficient engines, developing advanced robotics, or creating sustainable energy solutions, I am confident that a career in mechanical engineering will offer endless opportunities for growth and innovation.In conclusion, my journey towards mechanical engineering has been a testament to my passion for problemsolving and my love for the intricate world of machines. It has taught me the importance of perseverance, precision, and creativity, and has opened my eyes to the endless possibilities that await in this everevolving field. As I prepare to embark on the next chapter of my life, I am filled with anticipation and a deep sense of purpose, ready to contribute to the world of mechanical engineering and make a difference in the world.。
机械专业 英语作文
机械专业英语作文Title: The Role of Mechanical Engineering in Modern Society。
Mechanical engineering, as a cornerstone of modern technology, plays a pivotal role in shaping our society and advancing human civilization. From the design of intricate machinery to the development of cutting-edge technologies, the contributions of mechanical engineers are ubiquitous and indispensable. In this essay, we will delve into the significance of mechanical engineering in various aspects of contemporary society.First and foremost, mechanical engineering drives innovation and progress across industries. By harnessing principles of physics and mathematics, mechanical engineers design and optimize a wide array of products and systems, ranging from automotive vehicles to renewable energy technologies. For instance, in the automotive sector, mechanical engineers are instrumental in enhancing fuelefficiency, improving safety features, and reducing emissions through the design of lightweight materials, aerodynamic structures, and advanced propulsion systems.Moreover, mechanical engineering intersects with other disciplines to address global challenges such as climate change and sustainable development. In the quest for renewable energy sources, mechanical engineers play a pivotal role in the design and optimization of wind turbines, solar panels, and hydroelectric generators. Through innovation and research, they strive to make these technologies more efficient, affordable, and accessible, thereby facilitating the transition towards a greener and more sustainable energy landscape.Furthermore, mechanical engineering is at the forefront of technological advancements that revolutionize healthcare and improve quality of life. From the development of medical devices to the design of prosthetic limbs, mechanical engineers leverage their expertise to enhance diagnosis, treatment, and rehabilitation processes. For example, the design of robotic surgical systems enablesminimally invasive procedures with greater precision and reduced recovery times, ultimately benefiting patients and healthcare providers alike.In addition to its tangible contributions, mechanical engineering fosters interdisciplinary collaboration and fosters a culture of innovation and problem-solving. By working alongside experts from diverse fields such as materials science, computer engineering, and biomechanics, mechanical engineers tackle complex challenges and push the boundaries of what is possible. Through research, experimentation, and collaboration, they pave the way for breakthroughs that shape the future of technology and society.Furthermore, mechanical engineering education equips individuals with critical thinking skills, analytical abilities, and practical knowledge that are highly sought after in today's job market. Whether pursuing careers in aerospace, automotive, biomedical, or energy sectors, mechanical engineers are well-positioned to make meaningful contributions and drive positive change in their respectivefields. Additionally, the interdisciplinary nature of mechanical engineering enables professionals to adapt to evolving industry trends and embrace lifelong learning opportunities.In conclusion, mechanical engineering serves as a driving force behind technological innovation, sustainable development, and societal progress. From enhancing industrial processes to improving healthcare outcomes, the contributions of mechanical engineers are pervasive andfar-reaching. As we continue to confront global challenges and strive for a better future, the role of mechanical engineering in shaping our society will only become more pronounced and indispensable. Through collaboration, innovation, and a commitment to excellence, mechanical engineers will continue to push the boundaries of what is possible and create a world that is safer, healthier, and more prosperous for generations to come.。
机械专业英语论文1
Application and development of mechanical dynamicsBeginning of the 21st century, the development of dexterous manipulator, walking robots, machine tool, removable optical instrument platform, train, automobile active chassis as the representative of the intelligent electronic products will be one goal of China's machinery industry. Such mechanical and electrical products with innovative materials, structural lightweight, mobile, intelligent and high, resulting in a material nonlinearity, complex geometric nonlinear dynamics, nonlinear control with lag. These issues will be studied mechanical dynamics in the field of frontier in the early 21st century.First the contents of the mechanical dynamics：Any mechanical, while in the presence of motion, will be subject to the force. In the study Machinery and mechanical force generated by the movement in motion when the mechanical dynamics, and mechanical design and improvement of science from the perspective of the interaction force and movement. Detailed mechanical dynamics research can be divided into the following six:（1）At a known external force, required to have identified the true movement of the inertial parameters of the mechanical system; analysis of interaction between the various components of the mechanical motion; research institutions and balance theory and method of the rotary member; mechanical vibration analysis; and institutional analysis and synthesis, and so on.（2）Analysis of the interaction between the various components of the mechanical movement. Size and variation of the structural design of these forces is deputy campaign, the carrying capacity of supporting and component analysis and the choice of a reasonable basis for lubrication method. After obtaining the mechanical movement of the real force of inertia can be calculated for each member, and then based on Alembert principle determined by statics interaction between components. researching the institutional balance and the revolving member of theories andmethods.For rigid rotor balancing existing mature technologies and methods: both the theory and methods need further research to work flexible rotor speed approaches or exceeds the balance of the natural frequency of the rotor itself.（3）Relationship between balance and distribution of mechanical energy during operation. These include: mechanical efficiency calculations and analysis; theory and design governor; flywheel applications and design.Analysis of mechanical vibration is one of the basic elements of mechanical dynamics. It has developed into a content-rich, self-contained discipline.（4）Organizations and agencies comprehensive analysis of the general structure and motion mechanism is concerned, but with the improvement of the mechanical speed of operation, mechanical dynamics analysis and synthesis of high-speed has become an indispensable element when institutions.Second the mechanical dynamics of classification：Mechanical dynamics analysis process, according to their different functions can be divided into two types of problems:(1) Dynamics inverse problem: Given the state of motion and resistance mechanism (moment), the solution should be applied to the counterweight (balanced torque) on the driving member, and a variety of anti-vice campaign force, which is known campaign, seeking power.(2) The positive dynamics of the problem: Given the machine's input force (torque) and the resistance variation, the time to solve the movement of the machine, which is a known force, seeking movement.Third, the mechanical dynamics in modern mechanical systemsFrom the analysis, simulation to design and control, mechanical dynamics in the study area continues to expand, the formation of a number of branches, such as: machine tool dynamics, vehicle dynamics, rotor dynamics, robot dynamics, elastic body dynamics and soon on.(1) Machine DynamicsFor precision machine tools, the machining accuracy is important as an indicator, and the machine vibration is seriously undermined the machining accuracy. Complexexcitation force generated during cutting, gear transmission system, such as rolling bearings is the internal vibration source machine. Research machine dynamics are: the machine power source analysis, dynamic modeling and vibration machine vibration analysis and dynamic design of the machine.(2) Vehicle DynamicsWith high speed, safety and comfort of the vehicle becomes very important. And there were many unique dynamics, such as: Vibration wheels on the rails with a taper will lead serpentine movement of the train, it will stimulate the lateral movement of the vehicle; high-speed train on the rate of movement of the curve in the region when the major issues involved in vehicle safety; to improve the comfort of the car, when the latest research trends active vibration control of the frame, and the movement that inspire every moment according to the road, ready to adjust the parameters of the vibration system components, it is always in optimum damping condition.(3) Rotor dynamicsSteam turbines, generators, motors, centrifuges and other rotating machinery, the main rotor of their work. In order to improve the efficiency and capacity of the machine, increasing the speed of such mechanical. Suppress the vibration of the rotor system when key issues. Especially for large turbine generator rotor damage due to vibration caused by the national economy will result in significant losses. 1980s, China's two 200,000 ten million Turbine claiming the minor axis vibration caused serious incidents. Rotor dynamics and vibration of the rotor support system and countermeasures. It vibration of the shaft and the shaft early as the basis, but the operating speed turbine generator shaft exceeds the critical speed, but also contains a more complex and more vibration, thus forming an important branch of mechanical dynamics.(4) Robot dynamics1960s, robotics born and developed rapidly, it is the body, mechanical electronics, computer science and information science from a multidisciplinary frontier. A variety of industrial robots has become increasingly widely used in paint, handling, welding and assembly of industrial production line, all kinds of special robots are used inmarine exploration, outer space exploration and other fields. Robots learn to become a branch of the agency agency science hyperactive. In order to improve the speed of the robot, high-speed, flexible robot has emerged. The complexity of the robot mechanism far more than the general planar mechanisms, and must consider the dynamics of the robot control.Machine dynamics, vehicle, rotor and robots, which focuses on this type of machinery personality problems. The various types of machinery are included with institutions of various types of machinery and systems are a prime mover, transmission and composition of the working machine. Therefore, institutional dynamics and dynamics of mechanical systems in a variety of mechanical dynamics of the common problems.Fourth mechanical dynamics of the FutureA mechanical development of modern significant feature is that automatic adjustment and control devices are increasingly becoming an integral part of the machinery. Mechanical dynamics of the study has been extended to include the different characteristics of the power machine and control and regulation devices, including the entire mechanical systems, control theory has infiltrated into the field of mechanical dynamics.In some mechanical design, mechanical dynamics of change has made quality. Various simulation methods and testing theories and methods of movement and dynamic parameters, is increasingly becoming an important means of mechanical dynamics studies.。
机械专业英语短文带翻译
机械工程师的关键责任之一是设计与分析机械系统。这涉及使用计算机辅助设计（CAD）软件创建系统的详细三维模型，并在不同条件下模拟其性能。通过分析作用于系统组件的力、应力和振动，机械工程师可以优化设计，确保安全、可靠和高效。
Case Study: Designing an Automotive Suspension System
案例研究：汽车悬挂系统设计
例如，让我们考虑一下汽车悬挂系统的设计。悬挂系统负责在保持车辆稳定控制的同时提供平稳的行驶。机械工程师使用CAD软件设计悬挂系统的各个组件，例如弹簧、减振器和控制臂。
在完成初始设计后，工程师将使用有限元分析（FEA）软件对系统进行分析。这样可以模拟系统在不同的道路条件下（如坑洼或减速带）的行为。通过分析组件中的应力和位移，工程师可以确定潜在的设计问题，并进行必要的修改，以改善悬挂系统的性能和安全性。
For example, let's consider the design of an automotive suspension system. A suspension system is responsible for providing a smooth ride while maintaining the stability and control of the vehicle. A mechanical engineer would use CAD software to design the various components of the suspension system, such as the springs, dampers, and control arms.
After the initial design is complete, the engineer would then analyze the system using finite element analysis (FEA) software. This allows them to simulate the behavior of the system under different road conditions, such as potholes or speed bumps. By analyzing the stresses and displacements in the components, the engineer can identify potential design issues and make necessary modifications to improve the performance and safety of the suspension system.
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《专业英语》读书报告姓名：柳佳琛专业：机械设计制造及其自动化班级：08624学号：2008301390088分数：日期：2011年12月11日PART 1 English-Chinese TranslationLesson 48 Capitalizing on CAPP 后半部分原文：The first of these is the variant or retrieval method.In this method,the computer makes a search through its store of a number of standard or partially completed process plans that have been previously developed by human ing the current design data supplied by the CAD system,it searches for a plan that was based on a part of similar design.This search can make effective use of group technology design coding to simplify the search for similar code numbers,and hence for similar part designs.This original plan is then modified or completed by the human planner to suit the exact requirements of the current part design.The use of a computer and group technology to search for the most similar past design,and to retrieve the process plan for that design,significantly reduces the work required of the process planners.Their task becomes one of modifying the existing plan to suit the particular dimensions of the current part.They are required to perform the entire process planning method only in the case of a completely new part design.第一种是检索式工艺过程设计方法。
在该方法中,计算机通常搜索已存储的大量标准或部分完成的计划（由规划者先前规划的）。
通过使用由CAD系统供应的现存设计数据，设计者为新设计搜索的数据都是基于相似的零件设计。
这个搜索能能有效地利用成组技术译码来简化了为寻找相似代码或者相似零件设计的搜索过程。
随后，在最初的计划被规划者修改或完成来符合当前零部件设计的精确要求。
对计算机，搜索过去最相似的设计所使用的成组技术，以及为设计所检索的过程设计的使用，能有效减少过程的计划者的工作要求。
他们的任务变成了为现有计划修改以适应当前零件的特定范围。
他们被要求只在全新的零件的案例设计中演绎的整个过程规划方法。
The second method of computerized process planning is the generative method.In this method,the computer uses stored manufacturing and design data to generate a complete list of all possible process plans that could be used to manufacture the current part.It then exhaustively searches this list for the one which optimizes a specified cost function.This method always yields the optimal process plan for manufacturing a particular part.However,it has a very high cost in time and computer processing expenses.The computations required to produce even a single process plan for an arbitrary part design can be enormously complex.To repeat this for every feasible process plan of a part can become prohibitive.第二种方法是派生式工艺过程设计方法。
在该方法中,计算机利用储存的制造和设计数据来生成一个完整的列表所有可能的工艺计划（可以用于制造当前零件）。
然后计算机为这个计划详尽地搜索这个列表来优化其中规定的价值功能。
该方法总能生产为制造特定零件所需要的最佳工艺计划。
然而，在时间和计算机处理的花费方面，该方法的代价很高。
计算机的估算要求能够为一个零件工序设计一个单一的工序计划，并且这个估算相当复杂。
然而重复每一个可行的零件计划可以被禁止。
Both of these methods of computerized process planning can also be enhanced through the application of artificial intelligence(AI)technologies in the form of expert systems.In the variant method,AI techniques can be applied to perform the modifications to the selected process plan that are currently performed by a human planner.This involves formalizing the process by which the human planner modifies a retrieved process plan.This process is then captured in the expert system.两种计算机化过程规划的方法可以通过应用人工智能技术，以专家系统的形式来提高。
在检索式工艺过程方法中,可运用人工智能技术进行修改以来选择工艺计划（曾经被人工计划完成）。
这涉及到通过人工修订派生式工艺过程设计来使这个过程正式化。
接着这个过程就能被专家系统捕捉到。
This enables the expert system,in conjunction with the existing search process,to produce finished process plans of equivalent quality to the human finished plans.这使得专家系统通过结合现有的搜索过程来生产并完成工艺过程计划，并且这个计划与人工完成的计划等同。
PART 2 Technical WritingThe Book Report of CAPPProcess planning translates design information into the process steps and instructions to efficiently and effectively manufacture products. As the design process is supported by many computer-aided tools, computer-aided process planning has evolved to simplify and improve process planning and achieve more effective use of manufacturing resources.Alternatively, process planning is the systematic determination of the detailed methods by which parts can be manufactured from raw material to finished product. In recent years, computer aided process planning has been recognised as a key element in computer integrated manufacturing . In spite of the fact that tremendous efforts have been made in developing CAPP systems, the benefits of CAPP in real-life manufacturing environments are yet to be seen. With the rapid development of computer-aided techniques, both the design and implementation of CAPP have changed greatly since its development.At present, there are two general approaches to computer aided process planning variant and generative; each one is associated with specific planning techniques.1.Variant Process PlanningIt follows the principle that similar parts require similar plans. Therefore, the process requires a human operator to classify a part, input part information, retrieve a similar process plan from a database, and edit the plan to produce a new variation of thepre-existing process plan. Planning for a new part involves retrieving of an existing plan and modification. In some variant systems parts are grouped into a number of part families, characterized by similarities in manufacturing methods and thus related to group technology.2.Generative Process PlanningGenerates process plans utilizes decision logic, formulae, manufacturing rules, geometrybased data to determine the processes required to convert the raw materials into finished parts.It develops new plan for each part based on input about the part’s features and attributes. Due to the complexity of this approach a generative CAPP system is more difficult to design and implement than a system based on the variant approach. But a generative CAPP system does not require the aid of a human planner, and can produce plans not belonging to an existing part family. It stores the rules of manufacturing and the equipment capabilities in a computer system. The generative approach is complex and a generative system is difficult to develop.Proper combination of the two approaches can make an efficient CAPP system. First the system will check whether the process planning is possible for a new part by variant approach. If variant system is unable to identify the part to be of a previous group or family it will use generative technique for process planning. So both the variant and generative processplanning approaches need further development in parallel.Significant benefits can result from the implementation of CAPP. In a detailed survey of twenty-two large and small companies using generative-type CAPP systems, the following estimated cost savings were achieved:1.58% reduction in process planning effort2.10% saving in direct labor3.4% saving in material4.10% saving in scrap5.12% saving in tooling6.6% reduction in work-in-processIn addition, there are intangible benefits as follows:1.Reduced process planning and production leadtime; faster response toengineering changes2.Greater process plan consistency; access to up-to-date information in a centraldatabase3.Improved cost estimating procedures and fewer calculation errors4.More complete and detailed process plans5.Improved production scheduling and capacity utilization6.Improved ability to introduce new manufacturing technology and rapidly updateprocess plans to utilize the improved technologyFor the past three decades, computer-aided process planning has attracted a large amount of research interest. A huge volume of literature has been published on this subject. Today, CAPP research faces new challenges owing to the dynamic markets and business globalisation. Thus, there is an urgent need to ascertain the current status and identify future trends of CAPP. Covering articles published on the subjects of CAPP in the past 10 years or so, this article aims to provide an up-to-date review of the CAPP research works, a critical analysis of journals that publish CAPP research works, and an understanding of the future direction in the field. First, general information is provided on CAPP. The past reviews are summarised. Discussions about the recent CAPP research are presented in a number of categories, i.e.feature-based technologies, knowledge-based systems, artificial neural networks, genetic algorithms, fuzzy set theory and fuzzy logic, Petri nets, agent-based technology, Internet-based technology, STEP-compliant CAPP and other emerging technologies. Research on some specific aspects of CAPP is also provided. Discussions and analysis of the methods are then presented based on the data gatheredfrom the Elsevier's Scopus abstract and citation database. The concepts of ‘Subject Strength’ of a journal and ‘technology impact factor’ are introduced and used for discussions based on the publication data. The former is used to gauge the level of focus of a journal on a particular research subject/domain, whereas the latter is used to assess the level of impact of a particular technology, in terms of citation counts. Finally, a discussion on the future development is presented.The importance of CAPP in a modern manufacturing facility cannot be underestimated. CAPP provides a direct link between design and manufacturing. It reduces the time spent between part design and actual manufacture. The CAPP systems of the future should be dynamic, flexible and intelligent. The successors to intelligent systems will be "learning systems" that can monitor production and feed data back to the system. This feedback wilt become the teacher. The systems will be able to learn from manufacturing mistakes and therefore improve the performance. The advantages of a learning and self-adapting system should include more accurate time and cost estimates, improve productivity, ability to monitor processes, less variability, more reliability and reduced human involvement. The CAPP area has been greatly developed in the last two decades and many techniques have been involved. An attempt has been made to present the state-of-the-art of CAPP systems developed during the period 1989-1996. Some of the welt-known CAPP systems are discussed in this paper. The discussion focuses on the general aspects of the systems, such as, functions, working steps, approaches of implementation, methodologies of knowledgerepresentation, programming language, architecture, and pros and cons of the system.。