Design of a Method for Disassembly Works on Recycle Products

Matsumoto, Toshiyuki,Yahata, Yuko,Shida, Keisuke Korean Institute of Industrial Engineers 2009 Industrial Engineeering & Management Systems Vol.8 No.1

This study proposes a new framework for designing disassembly methods. In recent years, environmental problems have become global issues. Recycling of used products or resources is recognized as a matter of significance since it may help reduce the risk of exhausting natural resources. Considering possible exhaustion of limited natural resources in the near future, reuse of products would gain more environmental significance. As yet, it relies hugely on manual disassembly, which labor cost places burden on the total recycling cost. The purpose of this study is to propose a methodology designing for manual disassembly works, and a creation method of a jig. By focusing on parts' connection and attachment relationship, parts are categorized in 5 categories (parent part, joint key part, attaching key part, child part, and independent part) according to the features that parts possess, and 3 kinds of connection relationships (parent part-joint key part connection, parent part-independent part connection and child part-child part connection) are clarified. Connection relationship and attachment relationship charts have also been created, and utilizing them, disassembly orders are settled, and a disassembly jig is devised. The proposed methodology is also applied to a real product and its work time is improved 42% form 31 to 13 seconds.

Development and Implementation of a Skill Transfer System for a Self-Tapping Screw-Tightening Operation

Toshiyuki Matsumoto,Daisuke Doyo,Keisuke Shida,Takashi Kanazawa 대한산업공학회 2011 Industrial Engineeering & Management Systems Vol.10 No.3

Self-tapping screws have some operational peculiarities. In spite of their economical advantage that requires no prior tapping operation, a weakness of self-tapping screw-tightening operations is that screws can easily be tightened at a non-right angle, thus resulting in an improper tightening strength. Increases in outsourced workers have reduced labor costs, but the accompanying high worker fluidity means that new workers are more frequently introduced into factories. It is necessary to train new workers for self-tapping screw-tightening operations, which occupies a considerable portion of ordinary assembly works. The purpose of this study is to develop and implement a skill transfer system for the operation. This study (1) proposes a set of characteristic values for evaluating the quality of the operation and develops a device that can measure these values; (2) proposes criteria for evaluating the resultant quality of the tightening; and (3) develops a skill training system for better work performance. Firstly, sets of characteristic values for evaluating the quality of the operation, namely, torque, vertical pressure forces and horizontal vibration forces, are proposed. A device that can measure these values is developed. Secondly, criteria for evaluating the resultant quality of the tightening are identified, involving tightening torque, maximum vertical pressure and timing, vibration area during the processing and tightening period, and work angle. By using such parameters, workers with the proper aptitude can be identified. Thirdly, a skill training system for the operation is developed. It consists of screwdriver operation training and screw-tightening training with feedback information about the results of the operation. Finally, the validity of the training system is experimentally verified using new operators and actual workers.

Development and Implementation of a Skill Transfer System for a Self-Tapping Screw-Tightening Operation

Matsumoto, Toshiyuki,Doyo, Daisuke,Shida, Keisuke,Kanazawa, Takashi Korean Institute of Industrial Engineers 2011 Industrial Engineeering & Management Systems Vol.10 No.3

Self-tapping screws have some operational peculiarities. In spite of their economical advantage that requires no prior tapping operation, a weakness of self-tapping screw-tightening operations is that screws can easily be tightened at a non-right angle, thus resulting in an improper tightening strength. Increases in outsourced workers have reduced labor costs, but the accompanying high worker fluidity means that new workers are more frequently introduced into factories. It is necessary to train new workers for self-tapping screw-tightening operations, which occupies a considerable portion of ordinary assembly works. The purpose of this study is to develop and implement a skill transfer system for the operation. This study (1) proposes a set of characteristic values for evaluating the quality of the operation and develops a device that can measure these values; (2) proposes criteria for evaluating the resultant quality of the tightening; and (3) develops a skill training system for better work performance. Firstly, sets of characteristic values for evaluating the quality of the operation, namely, torque, vertical pressure forces and horizontal vibration forces, are proposed. A device that can measure these values is developed. Secondly, criteria for evaluating the resultant quality of the tightening are identified, involving tightening torque, maximum vertical pressure and timing, vibration area during the processing and tightening period, and work angle. By using such parameters, workers with the proper aptitude can be identified. Thirdly, a skill training system for the operation is developed. It consists of screwdriver operation training and screw-tightening training with feedback information about the results of the operation. Finally, the validity of the training system is experimentally verified using new operators and actual workers.

Design of a Method for Disassembly Works on Recycle Products

Toshiyuki Matsumoto,Yuko Yahata,Keisuke Shida 대한산업공학회 2009 Industrial Engineeering & Management Systems Vol.8 No.1

This study proposes a new framework for designing disassembly methods. In recent years, environmental problems have become global issues. Recycling of used products or resources is recognized as a matter of significance since it may help reduce the risk of exhausting natural resources. Considering possible exhaustion of limited natural resources in the near future, reuse of products would gain more environmental significance. As yet, it relies hugely on manual disassembly, which labor cost places burden on the total recycling cost. The purpose of this study is to propose a methodology designing for manual disassembly works, and a creation method of a jig. By focusing on parts’ connection and attachment relationship, parts are categorized in 5 categories (parent part, joint key part, attaching key part, child part, and independent part) according to the features that parts possess, and 3 kinds of connection relationships (parent part-joint key part connection, parent part-independent part connection and child part-child part connection) are clarified. Connection relationship and attachment relationship charts have also been created, and utilizing them, disassembly orders are settled, and a disassembly jig is devised. The proposed methodology is also applied to a real product and its work time is improved 42% form 31 to 13 seconds.

On the Subjective Effect of StirMark When Applied to Videos

Toshiyuki Yokoha,Tadashi Matsumoto,Shigeyuki Sakazawa,Liang Zhao,Hideo Yamamoto 대한전자공학회 2004 ITC-CSCC :International Technical Conference on Ci Vol.2004 No.7

Electro-Magneto-Thermo-Mechanical Properties of a SMA Plate and its Application to Adaptive Thermo-Flow Control

Toshiyuki Takagi,Junji Tani,Shunji Suzuki,Minoru Matsumoto 대한전자공학회 1995 대한전자공학회 워크샵 Vol.1995 No.-

Extending Fatigue Life of Out-of-plane Gusset Joint by Bonding CFRP Plates Under Bending Moment

Risa Matsumoto,Toshiyuki Ishikawa,Manabu Takemura,Yoshisato Hiratsuka,Hirotaka Kawano 한국강구조학회 2016 International Journal of Steel Structures Vol.16 No.4

Carbon fiber reinforced plastic, CFRP, plates bonding method is one of the new repair methods for fatigue cracks. In this method, propagation of fatigue crack will be delay because of the suppression of crack opening by crack bridging and stress reduction by composite effect of bonding CFRP plates. In this study, to clarify the effect of bonding CFRP plates on fatigue life extension, bending fatigue tests were carried out. First, fatigue tests on the specimens in as-welded condition were conducted until fatigue crack propagated to 10mm away from the weld toe. Then, fatigue crack was covered by CFRP plates and the specimens were re-tested until fatigue crack penetrated through the base plate. As the results of bending fatigue tests, the fatigue test data of the specimens repaired by bonding CFRP plates showed much longer fatigue life compared with that in as-welded condition, under stress ratio, R=0 and -infinity.

Prediction of Bending Fatigue Life of Cracked Out-of-Plane Gusset Joint Repaired by CFRP Plates

Risa Matsumoto,Takafumi Komoto,Toshiyuki Ishikawa,Atsushi Hattori,Hirotaka Kawano 한국강구조학회 2018 International Journal of Steel Structures Vol.18 No.4

Carbon fi ber reinforced polymer (CFRP), plates bonding repair method is one of the simple repair methods for cracked steel structures. In this study, the infl uence of width of CFRP plates on bending fatigue life of out-of-plane gusset joint strengthened with CFRP plates was investigated from the experimental and numerical point of view. In the bending fatigue test of cracked out-of-plane gusset joint strengthened with CFRP plates, the eff ect of width of CFRP plates on crack growth life was clarifi ed experimentally. Namely, it was revealed that the crack growth life becomes larger with increasing the width of CFRP plates. In the numerical approach, the stress intensity factor ( SIF ) at the surface point of a semi-elliptical surface crack was estimated based on the linear fracture mechanics. Furthermore, the extended fatigue life of cracked out-of-plane gusset joint strengthened with CFRP plates was evaluated by using the estimated SIF at the surface point and the empirical formula of the aspect ratio of semi-elliptical crack. As the results of numerical analysis, the estimated fatigue life of the specimen strengthened with CFRP plates showed the good agreement with the test results.

Development of a Computer Game "Ecopoly" for Education on Relationship between Environment and Economy

Tasuya Komuro,Toshiyuki Matsumoto 대한산업공학회 2011 Industrial Engineeering & Management Systems Vol.10 No.4

It is necessary for humans who have been facing environmental problems to build a sustainable society in which economic activities coexist with nature. To realize such goals, it is essential to promote and enhance environmental education, and to raise global awareness of environmental issues. As a preceding study, a board game "Ecopoly" based on the Kyoto protocol and the estate dealings game, was developed and the validity of environmental education was verified. This study further aims to develop a computer game "Ecopoly", based on the board game which enables us to learn the relationship between environmental problems and economic activities, and to learn more about environmental problems. This computer game enables to concentrate on it by automatic complicated calculations, and to get a higher visual effect compared with the board game. Experimental testing of the game was conducted with 13 college student subjects, and the validity of the game was verified.

A Fundamental Study for Creating 3D CG Animation of an Assembly Work

Hiroki Yamanaka,Toshiyuki Matsumoto,Shinji Shinoda,Akira Niwa 대한산업공학회 2012 Industrial Engineeering & Management Systems Vol.11 No.2

This paper presents a new mode of expressing a 3D assembly work for creating a 3D CG animation without judgment by human from minimal required information. In the field of manufacturing, there are favorable movements in the utilization of 3D CAD for 3D simulation to shorten lead time for product development and pre-production. But simulating an assembly work has troubles to need huge quantity of manually input data. This paper discusses what minimal necessary information for creating 3D CG animations of assembly works is, focusing on the features of assembly works. Furthermore, a new mode of expressing a 3D assembly work is proposed as “state/change transition diagrams” (SCTD), which express arbitrary scenes in an assembly work as “state” and describe a sequential assembly work with “state” and “change”, and the outline of its stepwise generation algorithm is also described. SCTD can be converted to a 3D CG animation of an assembly work without judgment by human. This paper focuses on the creating 3D CG animation of assembly works which workers use only their both hands.