This paper presents the effect of demand information sharing between a set maker and a component supplier in the electronic device industries. We extend the information sharing (collaboration) from lower level of planning (short- or intermediate-planning) to higher level of planning (long-term planning). Using a computer simulation model, this examines the performance of the supply chain under different information sharing methods. The result shows that information sharing of long-term planning improves the profits of the maker and supplier more than that of short- or intermediate-term planning. Furthermore, we will report on the result of examining the effect of information sharing with different demand patterns faced by the maker and cost structures.

View full abstract

[in Japanese]

View full abstract

Global Manufacturing requires effective logistic systems, which make an enterprise network as a virtual and productive manufacturing company. However. There is a difficult problem that each enterprise cannot have enough information such as shipping date, parts arrival date, and so on. This paper shows a planning data sharing method for global manufacturing using shop transportation. An advanced planning and scheduling (APS) system is used in an Internet infrastructure, while ship assignment and berth scheduling problems are concurrently resolved.

View full abstract

As for the manufacturing industry of future Japan, a customer's needs for a customization and for a delivery shortening demand are required increasingly. That is, "zero" product and middle product inventories and the change to the demand synchronization production which enables production by the shortest lead-time are required. For this reason, defining a group of products, and establishing a process design platform and a production platform is an important subject from a mid- and long-term viewpoint.

View full abstract

It is called the time of cashflow management, and e-business in recent years. A customer's needs are strengthening the tendency of diversification and the formation of short time for delivery increasingly. In a manufacturing industry, curtailment of much more stock, curtailment of an overhead cost, and short time-for-delivery correspondence are required, and conversion to the production system which for that can synchronize with demand is pressing need. This paper describes synchronization of the printed circuit board assembly process which is one of the necks of the present production process.

View full abstract

It is necessary to assign the workers at the appropriate position taking account of their difference of abilities. Adopting a worker's request to the assignment would attain the improvement of workers motivation. In this paper, we provide the worker assignment to bring out the best ability focusing on the individual worker's properties. The assignment plan has many criteria, where data envelopment analysis is adopted for multi dimensional evaluation.

View full abstract

In order to achieve efficient production in large item small volume production systems such as FMS (flexible manufacturing system). a scheduling have an important role. However, a schedule obtained in advance can not correspond to situation that high-priority order and machanical trouble are suddenly arised. In order to cope with such an unexpected situation, it is effective to carry out re-scheduling in real-time. But, in order to obtain a good solution which require mass computational power, it is said that the meta-knowledge which changes and performs a plan according to a situation is effective. This paper describes the system which achieves a real-time planning using the knowledge base incorporating meta-knowledge. The planner which uses meta-knowledge for the layer of a higher rank chooses a policy to be use scheduler such as SPT rule or EDD rule. Moreover, a better schedule can be obtained by adding more new meta-knowledge to a planner.

View full abstract

This paper deals with a real time scheduling system of a holonic manufacturing system for machining process. The holonic manufacturing system was proposed by HMS cooperative research project aiming at realizing more flexible control structures of the manufacturing systems which can cope with the variety of the products and the unscheduled disruptions, such as status changes of equipment and input of high priority jobs. Decision making procedures of individual holons are discussed in the paper to establish a decision making process based on utilities for the holonic real time scheduling systems.

View full abstract

This paper investigates next machine selection methods for real-time job shop scheduling with alternative machines. We propose a simple machine selection rule in which the local workload balancing among alternative machines and the minimization of total workload are both considered. Numerical experiments show that the proposed rule performed best among the real-time machine selection rules.

View full abstract

This paper describes the scheduling allocation system on a task and a facility assigned for skilled engineers in a shop floor. Recently a kind of production demanded by domestic factory is noticed to depend on skill of engineers deeply. Hence manufacturing information included such the skill cannot be analyzed and predicted exactly enough to be difficult to translate it into FA. This research proposed scheduling allocation system considering of the skilled engineers based on the sensibility evaluation quantified that distributes task, facility and the engineers informed in gantt chart.

View full abstract

Uncertain factors, such as emergency orders, in a manufacturing environment give a lot of disturbances to the existing schedule, and then increase performance of the production process. This paper proposes a distributed scheduling system, which can make coordination among manufacturing process, even if some unexpected events arise. In a practical research of a parts manufacturing firm in automobile industry, we develop a prototype system to apply our framework. This paper shows some idea of the distributed scheduling system and it's implementation.

View full abstract

Model of simulation system employed for operational planning and evaluation must be in a good correspondence with real manufacturing system when various changes happen. Instead of time-consuming and error-prone manual operations, an adaptive simulation-modeling paradigm is proposed towards automated updating. Major configuration changes and decision transformations are concluded and the corresponding design solutions with abstraction are presented respectively. The proposed simulation model is proved to be effective through experimental simulation system construction.

View full abstract

In Distributed Autonomous Production Control System (DAPCS), the structure of machining-work element, which needs for a process planning and an operation planning, has influences on a control ability of DAPCS, a processing time of process planning & operation planning of system-module and a communication load among system-modules. In order to examine the appropriate structure of machining-work element in DAPCS, we analyzed "control ability / processing time / communication load" by types of machining-work elements based on Machining feature, Tool or Machine. And we designed the concrete data structure of machining-work element and made the program for making the data of machining-work element from the solid model data of a product.

View full abstract

This paper describes the method which generates bending process plan for sheet metal bending with handing robot. In process planning for sheet metal bending with handing robot, grasping position and reposition timing must be determined as well as bending sequence, tools and gage position for measuring bending line. When grasping position of handling robot is determined on sheet metal, the deformation of sheet metal to a grasping position must be taken into consideration. In this method, The determining of grasping position is solved in analyzing the sheet metal deformation to a grasping position by using of finite element method. The algorithm for determining grasping position is shown as follows. Firstly, The CAD data of sheet metal flat pattern is triangulated by the method of Dealunay tringulation. And then, Subsequent shape of sheet metal part is constructed. Several grasping position candidates are specified, and the constraint on the position is specified. The deformation minimum grasping position candidate is indicated as grasping position.

View full abstract

Much emphasis has been given to minimize the time not only for design and manufacturing of products but also for development of manufacturing lines, in order to deliver products to market as soon as possible. However, planning, design and evaluation processes of manufacturing lines are very complicated, and individual engineers carry out the manufacturing lines' design based on their own experiences. It is now eagerly required to establish systematic methods and support tools, in order to support all the engineering processes for the planning, design, evaluation and redesign of the manufacturing lines. The objective of the research is to establish systematic methods and computerized support systems for manufacturing lines' design based on cluster analysis and sensitivity analysis.

View full abstract

In recent years, a small-lot production becomes in use, and a product life cycle is becoming short. Since it corresponded to them, a production system is also shifting to production with variety of volume and period. Various production systems, such as a Cellular Manufacturing System and an autonomous assembly robot system are invented, and the system is continuing to be changed forever. Those production systems are complicated as compared with conventional production systems. Therefore, in order to perform a simulation to them so much, the simulator excellent in flexibility and extendibility is required. In this research, each element which constitutes a production system is created as independent modules, and the simulator performed combing them is developed.

View full abstract

Many kinds of FA control software have reactive and event-driven behaviors. These behaviors can be expressed as Statecharts : a finite state machine with hierarchical states and with guards of transitions. In this research, Statechart-based automated testing method on software for FA is proposed. Generation of test sequence for testing on state-transitions and of test data for testing on guard conditions could be fully automated from Statecharts, and critical error in implementation could be tested systematically. The practical application showed its effectiveness on efficiency and quality improvement in control software development process.

View full abstract

Manufacturing industries in Japan have been faced with the problem of lost knowledge. Knowledge possessed by production engineers and workers and workers is usually hard to extract by the traditional method of artificial intelligence and knowledge engineering, since it is deeply related to the complicated conditions of the physical world. The authors' research group has developed a method for knowledge acquisition, storage, and utilization by using the technology of virtual manufacturing. The method, named Active Knowledge Archive (AKA), introduces the connections between the descriptions of knowledge applications and the digital models. For knowledge acquisition, a conrete situation of problem solving generated by virtual tools is presented to a knowledge holder. It is easier for the knowledge holder to remind and use his knowledge in the concrete situation. Each extracted information is associated to the virtual model for preserving the context of knowledge application and it can be retrieved with the similar conditions of other virtual models.

View full abstract

To support a cutting tool management system in distributed manufacturing industries, there must be a cutting tool database, which can provide information necessary for that purpose. This paper deals with the methodology to construct a cutting tool database and to manage of cutting tool information for distributed cutting tool management system using network. In the past study, by introducing STEP technology and using EXPRESS and EXPRESS-G, we designed an information model of cutting tools, thereby representing models of such basic tool database as parts structure, assembly, nominal size and real size. We proposed an EXPRESS early binding XML for capturing the nature of tool data model, and for generation the serialization format of an EXPRESS data model, and evaluating its usefulness.

View full abstract

This paper deals with the working tool model for process planning. We introduced the behavior model of cutting tool, working tool, as a feature models of machined shapes to connect the machining operation and machined shapes in previous reports. The working tool consists of the swept macro tool, the envelope of the swept macro tool, and the working edge. In this report, th egeometric representation of working tool is represented by its profile and path based on the geometric representation of Machining Features. Moreover, the process planning data model is proposed for representing the setup placement of the raw stock and the placement of the Working Step. We also introduce a removal volume that is the intersection between raw stock and Working Tool.

View full abstract

The system provides design drafts and assembly order for Lego Mindstorms based on functional requirements. The operator inputs functional requirements to the system. These requirements are analyzed for primitive functions by reference to the block library. Each primitive function corresponds to a function block such as tire, caterpillar or light sensor. A genetic algorithm is applied to generate arrangements of possible combinations of function blocks. To make connections among function blocks in each generated arrangement using connection blocks and to complete this arrangement as a robot body, a simple genetic algorithm is applied. This results in the generation of a design draft for the robot. Assembly order is generated by re-arranging whole blocks in bottom-up order.

View full abstract

The study deals with the development of CAD/CAM system for 5-axis machining in consideration with th esurface finish. In the study, inclination machining has been done using the ball end mill. Various changes of the tool attitude has been carried out since the inclination is used in order to avoid the machining using the tool tip of the cutting tool. We search the difference of surface appearance and surface roughness in terms of tool attitude. However, in the case of form machining, wherein, 5-axis control machining is needed, it is difficult to maintain the tool attitude when the tool interference is considered. This study aims at the development of the CAD/CAM system in order to create a tool path intended for improving the machined surface. The tool path is created in consideration with the machined surface quality of different attitude. The cutting start point, tool feed direction and tool attitude can be determined automatically by using the device method.

View full abstract

The study proposes a new machining method to create a sharp corner on over-hanged surfaces. Sharp corner on overhanging surfaces are difficult to machine in conventional way or even in 3 to 5-axis EDM machine especially if the surfaces have different angles. In present research, we try to machine the sharp corner using the new machining method. The 6-axis controlled machining using the non-rotational tool with the application of ultrasonic vibration has been applied, since they can set the non-rotational tool in an arbitrary position against the workpiece. From the experimental results, it shows that the 6-axis controlled ultrasonic vibration cutting is capable of producing a sharp corner on overhanging surfaces.

View full abstract

We report on ISO14649 proposed as CNC data model in next generation, replacing G code in usual. This standard is nearly completed for machining shape of a hole and 2.5D, but is not for machining free surface. This paper argues a merit and demerit of this standard for the purpose of machining die/mold consisting of free surfaces with high speed and high precision.

View full abstract

We apply ISO14649 CNC data model to machining system utilizing non-rotating tool, and test cutting free surface using this machining system. The application of ISO14649 makes this system to more intelligent and informative than current system using RS-274 (G codes).

View full abstract

This paper deals with a operation support method in machining. A framework of intelligent machining support is proposed. The framework augments operator's machining skill by coordinating operation planning and machining simulation. A conventional approach of operation planning with machining simulator is called simulation-based operation planning. The approach generates efficient plans only in predetermined situation, because the relationship between planner and simulator should be fixed in advance. A feature of proposed framework in user customization of the planner and the simulator. The customization activities of software are executed according to the operator's situation understanding. Then, proposed method is expected to applicable to the various machining situations.

View full abstract

This paper proposes a changing method of the machine tool performance adapted for production culture. The production culture changes with a countries or an era. Each production cultural sphere needs each survival processing method in belonging country and an era. So, it is necessary to correspond every manufacturing facility performance to the production culture. Therefore, we propose a method that an ambiguous cultural attribute modified method technical attribute by using a tree structure, and the technical attribute has quantified dignity with Quality Function Deployment (QFD). As a result, we carried out the feasibility study of the method by changing the NC parameter a changing method to adapt the machine tool performance for production culture was able to be shown.

View full abstract

Conventional production system simulators are mainly applied to the automated lines. But they are not available to so called human-oriented production system U-shaped line, because it is difficult to model worker behavior in such lines. This paper proposes a new modeling method of woker behavior for production line simulation. Behavior of workers are expressed by transition graph with nodes having three elements of "behavior", "machine" and "time". Our modeling method are applied to some U-shaped lines with production system simulators, and its effectness are shown.

View full abstract

The establishment of low-cost and multi-functional automation technologies are still indispensable to the industry today for enhancement of cost competitiveness. This study shed light on the human advantages in production environment : dexterity and flexibility with which the human performs most complicated and difficult tasks. This gives a clue to a new approach to automation. Especially, This paper focuses on the human task learning characteristics in parts supplying operation for assembling task, the area where automation is not full-fledged yet. In this paper, first, the two remarkable human characteristics are extracted. Next, based on this analysis, new themes to achieve efficient automation system is newly proposed.

View full abstract

Low-cost and multi-functional automation technologies are still indispensable to the industry today for enhancement of cost competitiveness. This study shed light on the human advantages in production environment : dexterity and flexibility with which the human performs most complicated and difficult tasks. This gives a clue to a new approach to automation. This paper mainly concerns a worker's characteristics of visual information with assembling parts. First, to solve the problem of a general automation line, NAGARA assembly system learning from human's performance is newly proposed. Then, the characteristic of human's assembly operation is analyzed as the first step to construct the low-cost NAGARA production system.

View full abstract

The hierarchizing interlock of sensors is always monitoring the surrounding area of a construction robot by using a radar sensor and an infrared sensor. When the operator approaches the robot, this system switches to a lower speed. And when he touches the soft-touching bumper switch, this system makes the robot stop immediately. According to the risk assessment of the construction robot, adequate sensors are arranged and layered based on their safe performance.

View full abstract

A hybrid micro machine tool is developed. This tabletop size machine tool can be applied for EDM, ECM, mechanical machining, laser processing, and complex machining which is combined each machining method. To study the basic performance of hybrid micro machine tool, a complex machining experiment is carried out with the developed machine tool. The complex machining has 3 steps : machining electrode by milling, hole shaping by EDM, and hole finishing by ECM. These steps are performed in sequence on the same machine tool. In order to evaluate a hybrid micro machine tool from the environmental point of view, machining energy, the volume of machining liquid, and installation space of hybrid micro machine tool are measured. The measured values are compared with estimated values when same complex machining is carried out with conventional machine tools. Machining energy, the volume of machining liquid, and installation space of hybrid micro machine tool areone-hundredth times smaller than that of conventional machine tool.

View full abstract

The study deals with a control of chamfering quality by an industrial robot. chamfering quality means property of chamfered edge shape for various functions. In order to perform chamfering by a robot, Try to categorize the chamfered edge shape according to its own function, i. e. "for safe", "for insertion" and "for design", these functions were not defined in the conventional design field. A tool path is generated using CAD data followed by conversion, to control the robot without requiring a teaching-playback operation. Adopt a non-rotational cutting tool instead of rotational tools for its capability of chamfering without scars and burrs. Develop a chamfering angle and width control device to compensate for positioning errors and to control the width and angle of chamfering part which is attached to the robot. From the experimental result, the system is found to have an ability of chamfering quality control by an industrial robot.

View full abstract

Strategy for manipulation of deformable thin objects is presented. First, the contact state between environment surfaces and the object is defined. Secondly, manipulations categorized into five types are defined and state transition paths are shown. Transition paths based on contact state between environment surfaces and the object are generated. Thirdly, a method in order to evaluate the transition paths quantitatively is proposed. Finally, a simple example is shown to demonstrate the validity of this method.

View full abstract

The study deals with the development of a software to perform path planning on the basis of CAD data for chamfering by an industrial robot. For a 6-DOF robot, it is important to generate control commands considering with cutting patterns, i. e. start point, end point and tool direction. Although they are usually decided by an experienced operator, in the article, they are decided automatically by employing a reference vector calculated on the basis of CAD data and by considering tool configuration. From the experimental result of the simulation and actual operation by the robot, the software is found to be effective to perform automatic path planning in real time.

View full abstract

Industrial robots with high performance have been developed and introduced to manufacturing processes. They have taken hard work away from labors. When industrial robots are operated for a new work, an operator must make an operation program for them on an actual manufacturing line. Teaching technique is utilized for making it, but it takes a lot of time and cost. A new method to make a robot program using virtual reality techniques off a manufacturing line is proposed, but it has difficultly of robot operations in a virtual space because of bad man-machine interfaces using a computer mouse and keyboard. In this paper, to overcome the drawbacks of current robot teaching off-line, a robot teaching system using virtual reality devices, which enable an operator to realize intuitive 3D-operation of virtual robots, is proposed and developed.

View full abstract

With the aim of reducing the lead times for the design and manufacturing of products produced upon receipt of order, we have constructed an Automatic Design/Manufacturing Support System with the following unique functions. The System performs the functions of automatic design based on various parameters inputted by a designer, creating the necessary drawings and forms automatically and transfers these to a manufacturing plant thus notifying the person in charge of production management. We have constructed an automatic design system incorporating these functions as a Web application type three-tier system applied with Web technologies.

View full abstract

This paper discusses a networked manufacturing system using DCOM (Distributed Component Object Model) to provide an easily configurable and rapidly changeable manufacturing environment. A component API (Application Programming Interface) concept is proposed and implemented using DCOM. A networked manufacturing system composed of open-architecture CNCs from different vendors can be quickly constructed and rapidly reconfigured in structure by using prefabricated component API. The experimental result shows effectiveness of the proposed implementation method.

View full abstract

To establish inverse manufacturing system is strongly required for reducing environmental loads. In this system, products are made from used products, parts and materials taken back from market, not only new ones. Focusing on factories, which produce these products in the inverse manufacturing system, complicated fluctuation of amount, quality and timing of these resources requires these factories very flexible. The purpose of this study is to derive several rules and conditions for operating these factories efficiently, through simulating these factories focused on material flow, considering the fluctuations.

View full abstract

Part-reuse should be a prime strategy for products with a short life cycle such as office automation appliances for facilitating material circulation in order to reduce environmental impacts. To improve efficiency of the inverse manufacturing system, it is necessary to coordinate production processes and disassembling processes so as to reduce effects of fluctuation caused by user's unpredictable behavior. This paper proposes methods of order control of reuse-parts in production plant and process control in disassembling plant by exchanging the process and inventory information between both plants. The effectiveness of the proposed methods is verified by means of life-cycle simulation.

View full abstract

Stimulated by the global environmental issues, needs for a new manufacturing paradigm are increasing. Such a new manufacturing paradigm should drastically reduce materials and energy consumptions, while maintaining quality of life, product quality, and corporate profits. To investigate the feasibility of such a manufacturing paradigm, life cycle design is an indispensable tool. On the other hand, upgradable artifacts, which can upgrade their functionality during operation and the remanufacturing stage, is an important type of artifacts for realizing inverse manufacturing, because they have longer life times, encourage reuse of components, and moreover, create new business chances at lower stages of product life cycles. In this paper, we clarify a decision making problem in upgradable artifacts design and propose an idea to suport such decision making by using "life cycle simulation (LCS) systems" that are currently developed by various researchers.

View full abstract

This paper is focused on application to the rapid life cycle scenario for the products that are short functional lifetimes using life cycle simulation. This simulation consists three types of reuse (i. e. parts reuse to the new product, parts reuse for repair and secondhand reuse), and three user groups (i. e. normal users, low-price products users and secondhand users). As an example of such a short functional lifetime products, the mobile phone is described. Using this life cycle simulation, the transition of the market share of the family products and the series products is simulated. The parts reuse to the new product supplies almost full parts of the next generation products, and each type of reuse reduces 51% of the waste. And applying the rapid life cycle scenario, reuse rate is increased, so users will take high product service without increase the material consumption and waste generation.

View full abstract

A support system of design, paying attention to product re-manufacturing, was proposed to meet the current situation of short lifetime for products and the demand for recycling. An evaluation on the disassemblability of products was done for the purpose of an easy take-out of the target parts, and a strategic component design with consideration of the reusability of products and the technological progress was proposed. An experiment was carried out upon the disassembling of a printer, and it was found that the easiness of disassembling could be comparable between the calculated process from entropy and that of the practical operation.

View full abstract

Manufacturing industries are facing borderless mega competitions to survive in a global market today. In order to defeat competitors, cost reduction and quality improvement should be done as a matter of course. But the most important point is when to market. As soon as customers' needs are clear, manufacturers should develop new products, install manufacturing systems, and put the products into a global market right on time. Such agility is indispensable for all manufacturers. To realize agility new engineering methods, such as concurrent Engineering, Simultaneous Engineering, and Virtual Enterprise, has been adopted and various information technologies, such as CAD, CAM, CAE, network, database, etc., are installed to support manufacturing system engineering activities through the manufacturing system life cycle, which covers designing, constructing, operating and recycling.

View full abstract