Tohru Ihara

Supporting the Reuse of Parts Based on Operation Histories of Products and Preference of Consumers

For the effective re-use of parts, each re-usable part is required to be under appropriate management throughout their life cycle. A hindrance to the circulation of re-used parts is behavior of users. The flow of re-used parts around the user is uncontrollable and unpredictable. Authors are proposing “Part agent system” that is the combination of network agent called “Part agent” and radio frequency identification chip RFID. This paper discusses the mechanisms how Part agents use the operation history of the parts and the user’s preference on maintenance of the parts to support their effective reuse.

Effect of Material Type and Tip Radius of AFM Probes on Nanosheets Groove Machining Accuracy

This paper presents results of groove machining of potassium niobate nanosheets using an atomic force microscope (AFM). Groove machining operations are performed using recently developed diamond coating (DC) and super sharp silicon (sss) probes. The results obtained using these probes are compared to results obtained using a conventional silicon (Si) probe in order to examine the effects of the material type and the tip radius of the AFM probe on groove machining accuracy.

A prototype safety system for new on-the-job training (OJT) in an anthropocentric cell manufacturing system

The anthropocentric cell manufacturing system (ACMS) discussed consists of a skill-based manufacturing scheduling system, a new on-the-job training (New OJT) system and a safety system. The New OJT was developed using e-learning and automated guided vehicle (AGV)-arm robot as a teacher for CNC machine training. Since the machines and the AGV-arm robot are automatic devices, controlled by computer programs, the dangers might arise during training. Therefore, the safety system is required to ensure that a learner will be safe. We propose a prototype of safety system with designed machine-protection in order to protect the learner from dangerous behaviours during a level 1 training of a New OJT in ACMS. The machine-protection focused on protection from danger using image processing with a background subtraction technique and comparison of objects’ position. We also evaluated safety assessments of the learners, consisting of human error probabilities (HEP) and a human error rate (HER). The prototype of this developed safety system showed that the machine-protection certainly raises a warning alarm when the learner rises into dangerous zones during the training. The evaluated safety assessments showed that our designed New OJT training level 1 course performed more efficient safety performance for self-training of the learner.

Anthropocentric Intelligence-Based Manufacturing

When designing a flexible computer-integrated manufacturing system (FCIMS) which is to be used worldwide, there are many problems that need to be addressed. These may relate to the cultural differences which exist in various regions or countries. Implanting technology designed for use in specific circumstances either ends in failure or friction. It is necessary therefore to understand the different value systems so that they may be built appropriately into manufacturing processes. “Understanding” in this context means clarifying the judgemental processes so that desirable manfacturing goals may be achieved [1]. This understanding may lead to the development of a manufacturing style which is suitable, say, for implementing flexible manufacturing systems in Asia. In essence, then, an aspect of anthropocentric intelligence-based manufacturing is to assist international co-operation in manufacturing by technology transfer. Social, cultural and enterprise factors implicitly influence the form of manufacturing technology used. The industrialized nations are moving towards increasing manufacture of human-sensitivity-oriented products and aesthetic objects. This form of manufacture may be interpreted as an application of anthropocentric intelligence-based manufacturing. Its core technology is the use of computer representation of the knowledge of experienced engineers to control processes.

A New Approach Manufacturing Cell Scheduling based on Skill-based Manufacturing Integrated to Genetic Algorithm

The skilled workers-based scheduling method was developed using the evaluation of workers skill levels and the application of genetic algorithm. The scheduling method was presented through the workers gantt-chart. The scheduling performance indexes were evaluated by a free time index (FTI), a skill level index (SLI), and a working time index (TWI). The results showed that the maximum of FTI and the SLI indicated significant improvement in production efficiency. Additionally, the lowest of a TWI indicated the minimum differences among man-hour of workers.

The general idea and usage of manufacturing knowledge data-contained differences of production culture

Activities of product design and manufacturing are carried out on a worldwide scale. Operations like outsourcing and fabless manufacturing occur frequently in both design and manufacturing processes to stimulate outbreaks of the abovementioned phenomena. In this situation, manufacturing knowledge data, that have been collected and used only by the same enterprise in the same place and within the same ethnic group up to now, are not sufficient or precise enough for making a plan of ongoing manufacturing. This paper tries to suggest an example of manufacturing knowledge data containing an element of production culture and to estimate a risk of manufacturing trouble that could happen between each production culture.

Workpiece-Centered Distributed System in the Shop Floors for Machining and Assembly

This paper proposes a new configuration of shop floors for machining and assembly to overcome problems emerging these days. Workpieces are provided with autonomy and intelligence, which gives the manufacturing system flexibility, adaptability and robustness. It will also facilitate human operators intervention to the manufacturing processes. Design concept of workpiece-centered distributed system is shown. Experiments are made successfully on partially implemented system with sensory functions.

On the Formation Mechanisms of Adhering Layer during Machining Metal Material

Built-up Layer (BUL)/Built-up Edge (BUE) formed on the tool surface can be treated as a protective, thermal barrier or lubricant films especially in the extreme severe conditions when machining the metal materials, which can sustain the tool effective and wear resistance. In order to have a thorough understanding of the adhesion effect during machining, experiments have been carried out to investigate the performance and the formation mechanisms of adhering layer on the carbide tool in machining of aluminium alloys A6063, carbon steel S45C and difficult-to-cut hardened steel S45C (H-S45C). The morphology of tool adhered surface was examined by employing Scanning Electron Microscopy (SEM), the dimensions of adhering layer were measured by Laser Scanning Microscopy (LSM) and the elements on the tool were analyzed by Electron Probe Micro Analyser (EPMA), respectively. The atomic-scale cluster adhesive friction model is proposed to explain the tool-chip contact conditions, which considers the nature of the shear strain, shear strain rate and temperature distribution in the secondary deformation zone. The model is a dynamic model and the rate equation approach can be applied to estimate the formation process of adhering layer during machining. Results have shown that the adhering layer will give rise to BUL on the tool rake face and the BUE on the cutting edge and clearance face.

Influence of High-Cycle Fatigue on Crater Wear Characteristics of Cemented Carbide Tool

Recently, in order to make positively use of the effect of adhesive layer, which works as Build-up edge or Belag on the tool surface during machining operation, there have many investigations on the technique to reduce the wear of cutting tool. However, the mechanism of wear on the rake face is unknown and the reason why the adhesive layer can resist the abrasion is also unclear.This study aims to propose a new crater high-cycle fatigue wear model depending on the tool adhesion model established by the surface cluster on the interface between the Tool-Work Piece. By using this model we can elucidate the mechanism of adhesive layer. When the chip flows on the rake face, the commensurate phase occurs in the surface cluster on the interface, and the surface cluster slides in the similar form of dislocation. At the same time, the strong chemical bonding among the surface clusters becomes the repeat force which can result in the fatigue failure on the tool, and the tool crater wear happens. The energy dissipation process associates with the vibration of cluster, which increases the tool temperature rapidly. Therefore, the crater wear is a damage process on the tool with the high-temperature and high-cycle fatigue.In this study, the mechanism of crater wear when the cemented carbide cut the carbon steel was investigated using the adhesion cluster model, and the crater wear model was proposed to estimate the properties of the adhesive layer.

Research on solar tracking composite control

At present in the field of solar thermal power, there are two types of solar tracking control modes as the date trajectory tracking and the optical test tracking. However, both of them have some disadvantages. As the date trajectory tracking in the lack of automatic adjustability, optical test tracking will use a large number of photoelectric detection devices. In order to solve the problems above, this paper carries out using genetic algorithm to improve original composite control, establishing two improved control schemes— genetic algorithm combined with the overall fit control schemes and dichotomy combined with local area genetic algorithm. Both of them not only save a large number of photoelectric detection circuit consumption but also ensure the tracking accuracy of the composite control. At the same time, the day trajectory tracking control system gets automatic adjustment ability. The research will reduce large-scale thermal power plant construction costs, and promote the development of solar thermal power generation.