再论先进制造技术及其发展趋势

此文是《先进制造技术及其发展趋势》的深化与补充。首先,指出制造业在国家发展中所占的战略地位。接着,从三个方面十二点详细地分析了先进制造技术发展的特色与趋势:产品本身,“精”、“极”、“文”;制造过程,“绿”、“快”、“省”、“效”;制造方法,“数”、“自”、“集”、“网”、“智”,并强调上述这些方面均应基于“制造”与“机械”这两个基点之上。最后,提出了先进制造技术发展的指导思想与我国应该优先发展的方向,强调必须自主创新,必须“以人为本”。     

Proposal of new eco-manufacturing feature interaction-based methodology in CAD phase

Following the environmental crises of recent decades, a turning point in the awareness of the fragility of ecosystems has been marked, i.e., environmental awareness. This has contributed to the development of various environmental laws and regulations such as the “Waste Electrical and Electronic Equipment,” the “Restriction of Hazardous Substances,” and the “Registration, Evaluation, Authorization and Restriction of Chemicals” regulations and the “Energy Using Products” Directives. Our work contributes to the development of eco-friendly product manufacturing processes. In order to estimate and optimize the environmental impacts of a product, most of the methodologies, concepts, and tools that integrate computer-aided design (CAD) and life cycle assessment systems generally exploit the feature technology at the level of each feature independently of the others, i.e., “microplanning.” The feature interaction technology (FIT) is treated only in few studies, but it is pivotal in the eco-manufacturing process. In this paper, we propose a new manufacturing-scenarios-based methodology by using FIT and a Multi-criteria Decision Support Method (MCDSM), which helps manufacturers maintain their marketplaces by producing goods in an eco-friendly way. In fact, this methodology helps designers choose from the CAD design phase the most ecological manufacturing process from possible existent scenarios in real time.     

Research on application of the Internet of things technology in financial leasing of intelligent manufacturing enterprises

In 2015, the State Council issued “Made in China 2025,” stating that the deep integration of information technology and manufacturing should be     

Research on Microelectromagnetic Relays

A new microelectromagnetic relay is presented and fabricated based on micromachining technology, aiming at the miniaturization and high manufacturing efficiency of electromagnetic relays. This microrelay is composed of a lower magnetic circuit, a planar exciting coil, and an upper magnetic armature. A complete magnetic circuit is composed, and the “ON” and “OFF” states are controlled by the current of the exciting coil. The dimension of this microrelay is 5 mm × 5 mm × 0.4–mm. The fabrication process mainly includes lithography, sputtering, electroplating, etching, sacrifice-layer technology, etc. Electromagnetic force is calculated theoretically. The calculation results are used for the optimization design of the armature and the number of turns of the exciting coil. A microelectromagnetic relay is fabricated and the initial test results are given. The resistance of the exciting coil is about 300 Ω. The switch-on state resistance is about 1.7 Ω at an exciting current of about 50–mA. Translated from Journal of Beijing University of Technology, 2004, 30(2) (in Chinese)     

Assessment of manufacturing systems reconfiguration smoothness

The effect of the configuration selection on the smoothness and easiness of manufacturing systems reconfiguration process cannot be neglected, especially when dealing with reconfigurable manufacturing systems (RMS). The term “reconfiguration smoothness” is introduced in this paper to address this issue. In order to evaluate the level of reconfiguration smoothness (RS), a metric was developed to provide a relative measure of the expected cost, time, and effort required to convert from one configuration to another. This metric is composed of three components representing different levels of reconfiguration, namely; market-level reconfiguration smoothness (TRS), system-level reconfiguration smoothness (SRS), and machine-level reconfiguration smoothness (MRS). Rules are introduced to guide the development of execution plans for system-level reconfiguration, which we call “reconfiguration planning”. These plans help reduce the physical effort of reconfiguring the system. A case study is presented to demonstrate the use of the developed metric followed by sensitivity analysis to show the effect of changing different metric parameters. The results show how the developed metric provides a powerful relative assessment tool for the transitional smoothness between a current configuration and a number of candidate feasible configurations for the next period. This can affect the configuration selection decisions at the beginning of each configuration period.     

Distributed flexible reconfigurable condition monitoring and diagnosis technology

As manufacturing becomes increasingly decentralized, flexible and reconfigurable, more research needs to be done on monitoring and diagnosis technology that accommodate these new trends. The distributed condition monitoring and diagnosis technology based on the “flexible and reconfigurable” concept is studied here. A condition monitoring diagnosis model based on the distributed flexible and reconfigurable idea is proposed in this paper. The component makeup and functions of this model are discussed in detail. The model can fulfill in most instances the manufacturing system requirements for changing the configuration of the monitoring diagnosis system according to different manufacturing system configurations. This model also realizes the flexibility and reconfigurability of the monitoring diagnosis system in some degree. The model has already spawned a successful prototype for monitoring a chemical plant in accomplishing monitoring and control of the production process and equipment. Finally, some future research work is pointed out. __________ Translated from Chin. J. Mech. Eng., 2004, 40 (3) (in Chinese)     

Automated inspection system for headlamp reflectors

Up to now the quality control of headlamp reflectors for vehicles has been visually made by inspectors (100%-control). The results depend on the daily constitution and attention of the inspectors. In many cases, those “human factors” lead to dissatisfactory quality control and rejects due to assumed defects. To avoid this and to accordingly reduce production costs and save the environment, a manufacturer of image processing systems and the three biggest manufacturers of car reflectors in Europe have initiated a project with the intention of solving the current problems. This article gives an overview of the project under the aspect of the economical automation of the whole process of the car reflector inspection. The project began in May 2002 and finished in December 2004 and was supported by the European Commission under the 5th framework competitive and sustainable growth, FINDER, project no. G6RD-CT-2002-00668 [EC-research-program, 2001, Fast intelligent defect recognition system (FINDER)]. The work described in this paper is a summary of the technical reports from the authors made for this project [4–8].     

Effect of boundary layer swirl on supersonic jet instabilities and thrust

This paper reports the effects of nozzle exit boundary layer swirl on the instability modes of underexpanded supersonic jets emerging from plane rectangular nozzles. The effects of boundary layer swirl at the nozzle exit on thrust and mixing of supersonic rectangular jets are also considered. The previous study was performed with a 30° boundary layer swirl (S=0.41) in a plane rectangular nozzle exit. At this study, a 45° boundary layer swirl (S=1.0) is applied in a plane rectangular nozzle exit. A three-dimensional unsteady compressible Reynolds-Averaged Navier-Stokes code with Baldwin-Lomax and Chien’sk-ε two-equation turbulence models was used for numerical simulation. A shock adaptive grid system was applied to enhance shock resolution. The nozzle aspect ratio used in this study was 5.0, and the fully-expanded jet Mach number was 1.526. The “flapping” and “pumping” oscillations were observed in the jet’s small dimension at frequencies of about 3,900Hz and 7,800Hz, respectively. In the jefs large dimension, “spanwise” oscillations at the same frequency as the small dimension’s “flapping“ oscillations were captured. As reported before with a 30° nozzle exit boundary layer swirl, the induction of 45° swirl to the nozzle exit boundary layer also strongly enhances jet mixing with the reduction of thrust by 10%.     

纳米技术为我国制造业发展带来的新机遇

纳米技术是本世纪发展最快的实用技术之一，它与制造业息息相关。文章从产业革命的角度论述了纳米技术对制造业产生的三方面影响：从宏观制造向微观制造发展；冲击传统的制造方法、工艺和手段；制造过程及零件材料不再单一。同时指出振兴我国制造业的是抓住这次机遇创新工艺及其方法。对此，作为制造业采取多方面的应对策略，包括放正位置、找准目标、加强基础、理工结合、培养人才等，才能不误战机，赶超世界先进水平。     

Manufacturing cell formation using modified ART1 networks

The primary objective of group technology (GT) is to enhance the productivity in the batch manufacturing environment. The GT cell formation problem is solved using modified binary adaptive resonance theory networks known as ART1. The input to the modified ART1 is a machine-part incidence matrix comprised of the binary digits “0” and “1”. And the outputs are the list of part families and the corresponding part list, machine cells and their corresponding list of machines, and the number of exceptional elements. This method is applied to the known benchmarked problems found in the literature and it is found to outperform other algorithms in terms of minimizing the number of the exceptional elements. The relative merits of using this method with respect to other known algorithms/heuristics in terms of computational speed and consistency are presented .     

Reliability-based design for automobiles in China

The level of automobile design and manufacturing is an important sign of leadership in science and technology and economic power. The achievements of theories and methods for reliability-based design of automobiles in China are reviewed. For reliability-based design, the theories and practices, optimization, sensitivity, and robustness are estimated. The techniques of reliability-based design for automobiles are developed. The techniques service to the “hollow” phenomena of kernel technology, product innovative power, and independent development power can be solved.     

Digital manufacturing-the development direction of the manufacturing technology in the 21st century

After introducing the concepts of digital manufacturing technology, the discipline framework of digital manufacturing is presented in the paper by discussing its basic concept, theory foundation, key technology and scientific problems in detail. As the core of the advanced manufacturing technology, digital manufacturing is gradually becoming the main manufacturing technology of the twenty-first century. Firstly, the main features of digital manufacturing are indicated and its key supporting technologies are investigated by grouping them into four levels related to product development, numerical control, production management, and enterprise collaboration, respectively. Moreover, the existing problems in the research on the multi-discipline theory foundation of digital manufacturing such as manufacturing informatics, computational manufacturing, and manufacturing intelligence, are also indicated. Then, the core scientific problems of digital manufacturing are discussed in depth, which focuses on digitization of manufacturing information, modeling of manufacturing constraints, high-speed and high-precision numerical control theory, and Internet-based collaboration and integration. Lastly, the development trends and application perspectives of digital manufacturing are concluded. __________ Translated from Digital Manufacturing Science, 2003, 1(1–4) (in Chinese)     

Measurement and Characterization of “Resonance Friction” at High Sliding Speeds in a Model Automotive Wet Clutch

The friction forces between various lubricated “friction materials” and sapphire disks were measured using a new “high-speed” rotating disk attachment to the surface forces apparatus (SFA). Two different clutch lubricants and two different friction materials were tested at sliding speeds and normal loads from 5 to 25 m/s, and 0.2 to 1 N (nominal pressures ~1 MPa), respectively. The results show that “resonance friction”—characterized by large amplitude oscillatory (i.e., sinusoidal) vibrations, also known as shudder or chatter—dominates dynamical considerations at high sliding speed, replacing the smooth sliding or low-amplitude stick–slip that is characteristic of low speed/low load sliding. The characteristic (rotational) speeds or frequencies at which resonance friction occurs depend only on the coupled/uncoupled mechanical resonance frequencies of the loading and friction-sensing mechanisms. In contrast, the intensity of and time to enter/exit shudder depends strongly on the lubricating oil and, to a lesser extent, on the friction material. Physical–chemical analyses of the friction materials before and after testing showed that the samples undergo primarily structural rather than chemical changes. Our results provide new fundamental insights into the resonance friction phenomenon and suggest means for its control.     

Rapid and cost-effective manufacturing of high-integrity aerospace components

This paper presents a comprehensive set of theoretical investigations and industrial applications of computer-based rapid manufacturing technology for high-integrity aerospace components. Two rapid manufacturing processes have been proposed by integrating rapid prototyping, high-speed machining (HSM), reverse engineering and geometric computation theory. They have been validated through trial manufacturing of a matrix of current aerospace components embracing critical design features to be found across the aerospace industry. Applied to future development programmes, this research will provide aerospace companies the benefits of significant decrease in product introduction lead-time, savings in non-recurring product introduction costs and considerable reduction in manufacturing costs for “one off” and low volume service parts. The findings can also be applied to rapid prototype development in other industries, such as automotive and military.     

Mass Customization: Metrics and Modularity

Mass customization as a competitive strategy is getting progressively increasing attention in business and academic arenas due to its high potential to provide sustained strategic advantage in a unique fashion. It is well documented that a manufacturing company competes with others in its industry on five dimensions: Price, quality, flexibility, delivery, and service. According to the existing literature, mass customization provides significant strategic advantage in two of these dimensions—price and customization. We, however, argue that when properly implemented, the cellular manufacturing structure associated with the appropriate implementation of mass customization strategy, provides additional competitive value in quality and delivery. Furthermore by virtue of the customer co-design as an integral aspect of mass customization, customer satisfaction also improves under this strategy. Mass customization strategy, therefore, provides competitive advantage in all five competitive dimensions simultaneously—a truly unique strategic accomplishment. We also propose, in this paper, new metrics for mass customization strategy that measure the “mass” as well as the “customization” aspects of this strategy. Finally, we describe in the clearest terms the modus operandi of modularity in product design and the role it plays in bringing about high levels of customization on one hand and economies of scale at component level, on the other. We conclude with remarks that underscore the need for conducting research in the areas at the interface of mass customization and supply chain management.     

Fast algorithm of detection of boundary points in images

A method of detecting boundary points in brightness images, based on subpixel calculation of the brightness difference, is proposed. In a fragment 4×4 pixels in size, this method allows calculating 12 directions of the jump in brightness; the algorithm complexity is ∼34N atomic operations. The method considered is compared with available methods of detection of boundary points in the image. The algorithm proposed is demonstrated to be more stable to the “salt and pepper” noise, ensures more stable determination of the brightness jump direction, and provides a more intense response to the signal. An application of the method is noted.     

A manufacturability advisor for spun and rollformed sheet metal components

In today’s manufacturing scenario, accounting for manufacturability considerations at the product design stage is not an option but a necessity. When CAD/CAM tools are used to reduce design lead times, accounting for manufacturing process related considerations implicitly is often difficult. Availability of manufacturability advisor systems that analyze part geometry and other product related information for ease of manufacturing could be a solution to this problem. The purpose of a manufacturability assessment is to give feedback to the designer in order to make the product/process more effective. Present research is concerned with the development of an automated manufacturability advisor for sheet metal components. Unlike most of the work done in the past that concentrated on bending and other forming processes, present work deals with sheet metal components manufactured by two different processes, namely “spinning” and “rollforming”. Effectiveness of the proposed manufacturability advisor is demonstrated by taking the number of industrial parts as examples.     

Study on affecting factors of collaborative product development based on collaboration hierarchy model

Aiming at the levels of collaborative degree in web-based product development, a collaboration hierarchy model of this product development is developed in this paper. Based on the model, the affecting factors on collaboration levels are analyzed systematically from many aspects, such as technology, organization and business. A gap analysis method is studied in detail, and is applied in a real project. The application shows that it can solve the diverse problems of collaborative product development effectively, and help enterprises find out the critical factors that affect the collaboration. Translated from Modern Manufacturing Engineering, 2006, (6): 1–3, 9 [译自: 现代制造工程]     

Technological information concerning the integrated design of “net-shape” forged parts

This work concerns knowledge integration from manufacturing activities in design in order to make full use of the advantages provided by “net-shape” forging processes, by setting up tools and using specific competencies. The main objectives are improvements in product quality, together with a time reduction required for the design and manufacturing cycle. The specific aspects of this work are to be found in the identification of the pertinent data, information, and knowledge in a context of redesigning industrial products in relation to evolutions in the manufacturing processes. The approach described here is based on analysis of the stages in the product life cycle. This approach is illustrated by the example of forged pinions used in automotive vehicle differentials, and it shows the improvements obtained mainly through design activities. A feature approach is mentioned in perspective in order to make it easier to formalize and capitalize on pertinent information through its integration in a product data management (PDM) system.     

Research on the overall architecture of Internet of Things middleware for intelligent industrial parks

With the continuous development of the Internet of Things technology and the proposal of “Made in China 2025”, the construction of IoT applicat