国際的な研究者の育成と海外との研究交流 - Department of Precision

第5章
国際的な研究者の育成と海外との研究交流
IIASA –Kyoto University
The Third Joint International
Seminar on Applied Analysis and
Synthesis of Complex Systems
(ASCS 2006)
The 21st Century COE Program for Research and Education on
Complex Functional Mechanical Systems, Kyoto University
IIASA – Kyoto University
The Third Joint International Seminar on Applied Analysis and
Synthesis of Complex Systems (ASCS 2006)
June 29-30, 2006.
International Institute for Applied Systems Analysis
Laxenburg, Austria.
Kyoto University
Graduate School of Engineering
Departments of Mechanical Engineering and Science,
Micro Engineering, and Aeronautics & Astronautics
Graduate School of Informatics
Department of Applied Analysis and Complex
Dynamical Systems
International Innovation Center
IIASA – Kyoto University
The Third Joint International Seminar on Applied Analysis and
Synthesis of Complex Systems
The 21st Century COE Program for Research and Education on Complex Functional
Mechanical Systems, Kyoto University
June 29-30, 2006.
International Institute for Applied Systems Analysis
Laxenburg, Austria
Final Agenda
29 June, Wodak Room
SESSION 1: Opening Session
9:30 – 10:00 Welcome Address,
Leen Hordijk, IIASA Director
Greetings from Seminar Organizers
Marek Makowski (IIASA, Austria) and Tetsuo Sawaragi (Kyoto
University, Jp.)
Greetings from Honorary Evaluators,
Gunnar Johannsen (Kassel University, Germany) and Martin Buss
(TUM, Germany)
10:00 – 10:45 Overview of COE and Emergence of Adaptive Motor Function
through Interaction among the Body, Brain, and Environment,
Kazuo Tsuchiya (Kyoto University, Jp.)
10:45 – 11:15 Coffee break
11:15 – 12:00 Soft Dynamical Systems with and for Humans,
Tetsuo Sawaragi (Kyoto University, Jp.)
12:00 – 13:30 Lunch
SESSION 2: Kyoto University COE Session (1)
13:30 – 14:00 Multi-Stage Quality Information Model for Managing Complex
Production System,
Hajime Mizuyama (Kyoto University, Jp.)
14:00 – 14:30 Synchronization of Human Walking Rhythm with Lateral Vibration
in Pedestrian Bridge,
Hiroshi Matsuhisa (Kyoto University, Jp.)
14:30 – 15:00 Reconstruction of the knee joint using the total joint regeneration
system,
Naohide Tomita (Kyoto University, Jp.)
15:00 – 15:30 Coffee break
SESSION 3: Invited Keynote Speech Session (1)
15:30 – 16:30 Semiotics and Intelligent Control (invited),
Morten Lind (Technical University of Denmark, Denmark)
16:30 – 17:15 Remembering by doing: An ontogenetically developed interaction
history for artificial social intelligence (invited),
Naeem Assif Mirza (University of Hertfordshire, UK.)
18: 00 – 21:00 Social Event at Heuriger
30 June, Wodak Room
8:00 – 9:30 Canadian Breakfast* at IIASA
* This is a sort of traditional event (a picnic-type social event) organized every
year in this season by IIASA and is a good opportunity to meet with many of
IIASA people. Details will be annouced on June 29 at the seminar.
SESSION 4: Invited Keynote Speech Session (2)
9:30 – 10:30 Biosemiotic Technology for Creating a Truly Sustainable Production
System (invited),
Jesper Hoffmeyer (University of Copenhagen, Denmark)
10:30 – 11:00 Coffee break
SESSION 5: Invited Keynote Speech Session (3)
11:00 – 12:00 Cell Biology of Mechanoadaptive Bone Remodeling (invited),
Vincent Everts (ACTA - Vrije Universiteit Amsterdam,
Netherlands.)
12:00 – 13:30 Lunch
SESSION 6: Kyoto University COE Session (2)
13:30 – 13:45 Overview of the Researches of Complex Material Group,
Takayuki Kitamura (Kyoto University, Jp.)
13:45 – 14:15 Rheology of Mechanosensitive Bone Cells (invited),
Rommel G. Bacabac (ACTA - Vrije Universiteit Amsterdam,
Netherlands.)
14:15 – 14:45 Mechanosensing Behavior of Cell Network System in Bone Tissue
Matrix,
Mototsugu Tanaka (Kyoto University, Jp.)
14:45 – 15:15 Computational Modeling and Simulation of Mechanobiology in
Bone Functional Adaptation by Remodeling,
Taiji Adachi (Kyoto University, Jp.)
15:15 – 15:45 Coffee Break
SESSION 7: Closing Session
15:45 – 16:15 Comments from Honorary Evaluators and Seminar Organizers
16:15 – 16:30 Concluding Remarks,
Kazuo Tsuchiya (Kyoto University, Jp.)
Project Leader of Kyoto University 21st Century COE Program on Research and
Education on Complex Functional Mechanical Systems
Prof. Kazuo Tsuchiya
Department of Aeronautics & Astronautics
Graduate School of Engineering, Kyoto University
Sakyo, Kyoto 606-8501, Japan.
E-Mail : [email protected]
HONORARY EVALUATORS
Prof. Gunnar Johannsen,
Dept. of Mechanical Engineering,
University of Kassel, Gemany.
Prof. Martin Buss
Institute of Automatic Control Engineering (LSR),
Technische Universitaet Muenchen, Germany.
ASCS 2006 Seminar Organizers
(IIASA)
Dr. Marek Makowski
IIASA (RMS)
Laxenburg, Austria.
E-Mail : [email protected]
(Kyoto University)
Prof. Tetsuo Sawaragi
Dept. of Mechanical Engineering and Science,
Graduate School of Engineering, Kyoto University
Sakyo, Kyoto 606-8501, Japan.
E-Mail : [email protected]
SEMINAR HOTEL FOR NON-IIASA PARTICIPANTS
Hotel for the Participants of the seminar (Already Booked)
The Hotel Schloss Weikersdorf
A - 2500 Baden near Vienna, Schlossgasse 9-11
Tel.: +43 2 252 483 01 - 0
Fax: +43 2 252 483 01 - 150
http://www.hotelschlossweikersdorf.at/ahi/hotelschlossweikersdorf/default_en.asp
http://www.expedia.com/pub/agent.dll?qscr=dspv&&itid=&itdx=&itty=new&from=m
SEMINAR SECRETARIAT
(IIASA)
Kate KENYON
Integrated Modelling Environment
IIASA
International Institute for Applied Systems Analysis
A-2361 Laxenburg, Austria
E-Mail: [email protected]
Phone : +43 2236 807456
Fax : +43 2236 807466
(Kyoto University)
Shinobu MINATO
Secretary
Sawaragi Laboratory
Dept. of Mechanical Engineering and Science,
Graduate School of Engineering, Kyoto University
Sakyo, Kyoto 606-8501, Japan.
Tel & Fax : +81-75-753-5233
E-Mail : [email protected]
November 2006
Report on
IIASA – Kyoto University
Third Joint International Seminar on Applied Analysis and
Synthesis of Complex Systems
June 29-30, 2006
Gunnar Johannsen
Professor of Systems Engineering and Human-Machine Systems
Institute for Measurement and Automation
Department of Mechanical Engineering
University of Kassel
Germany
1. Introduction
The "Third Joint International Seminar on Applied Analysis and Synthesis of Complex
Systems" of IIASA and Kyoto University was held on June 29-30, 2006 at the International
Institute for Applied Systems Analysis (IIASA) in Laxenburg, Austria.
As in 2004, the seminar was a joint initiative of Kyoto University and IIASA with the main
objectives of reporting on new research findings, as well as exchanging ideas and discussing
about concepts and methodologies for analysis and modeling of complex systems. The COE
program "Center of Excellence for Research and Education on Complex Functional
Mechanical Systems" at Kyoto University belongs to the COE (Center of Excellence) Program
of the Japanese Ministry of Education, Culture, Sports, Science and Technology (MEXT). The
COE Project Leader is Kazuo Tsuchiya of Kyoto University, the Seminar Organizers have been
Marek Makowski of IIASA and Tetsuo Sawaragi of Kyoto University.
2. Presentations at the Seminar
The seminar was opened with greetings by Tetsuo Sawaragi and by Marek Makowski, also
with a welcome address on behalf of the IIASA Director Leen Hordijk. A further brief opening
address was given by Gunnar Johannsen as Honorary Evaluator. The second Honorary
Evaluator, Martin Buss, had apologized at short notice for being unable to participate because
of illness.
The Project Leader of the COE, Kazuo Tsuchiya, presented an overview as an introduction for
the Interim Status Report of the COE program at this seminar. The purpose of the seminar was
described as to explain the interim status in more detail and to outline the research plan of the
second half of the COE program, focusing on the research topics in the fields of material
1
science and systems engineering. This relates to the two research groups of the COE program
(1) Complex System Control and Design Group, and (2) Materials Group. A special remark
was mentioned by Kazuo Tsuchiya as feedback from the COE Program Committee: “Because
this research covers a wide variety of subjects, collaboration with researchers from an even
more broad distribution of fields is needed.” This has also been considered with the invitation
of appropriate keynote speakers at this seminar. Further, Kazuo Tsuchiya talked about
"Emergence of Adaptive Motor Function through Interaction between Body, Brain, and
Environment" with applications in system biomechanics. Adaptive motor behavior is
investigated as an intelligent function, called mobiligence.
The Leader of the Complex System Control and Design Group, Tetsuo Sawaragi, presented his
work on "Soft Dynamical Systems with and for Humans". These systems are characterized by
biologically inspired architectures. Self-organizing mechanisms and evolutionary computations
are brought together. The importance of semiosis, i.e. of sign processes, for the communication
between humans, artifacts, and environments has been elaborated. A paradigm shift from
design for manufacture to design for nurture shall lead to a comprehensive reconfigurability of
human-oriented technology.
The research of Hajime Mizuyama on "Multi-Stage Quality Information Model for Managing
Complex Production System" proposed an explorative data analysis framework for
hypothesizing about causal factors and defect-causing mechanisms. – The presentation by
Hiroshi Matsuhisa dealt with the "Synchronization of Human Walking Rhythm with Lateral
Vibration in Pedestrian Bridge". Experimental and modeling works explain human locomotion
with the pull-in effect of the human gait rhythm into the ground swinging frequency, e.g. of a
pedestrian bridge. Two reasons for this effect (neural oscillator, starting motion and posture
control) have been theoretically investigated and experimentally verified. – Naohide Tomita
reported on his progress "From Function Designing to Bio-Environment Designing". Several
biological and clinical approaches for tissue-engineering treatment have been introduced.
Two invited keynote speeches elaborated on semiotics with different application domains.
Morten Lind presented his view on "Semiotics and Intelligent Control". Currently,
mathematical concepts of control theory and information processing concepts of artificial
intelligence dominate intelligent control and robotics research. However, sign relations are
needed with meanings for sensory data and control actions. This calls for systems semantics.
Semantic complexity and meaning structures as well as different dimensions of signification
have been explained. – The other keynote speech by Jesper Hoffmeyer dealt with "Biosemiotic
Technology for Creating a Truly Sustainable Production System". Biotechnology is now
developing in the direction of more integrated levels of cellular and organismic semiotic
functionality. Dangers and promises of biosemiotic technology have been mentioned.
A third invited keynote speech by Naeem Assif Mirza dealt with "Remembering by Doing: An
Ontogenetically Developed Interaction History for Artificial Social Intelligence". Sensorimotor
maps are generated from unknown sensor and actuator layouts. Rhythm, timing, and temporal
horizon of non-verbal communication as well as interaction histories have been explained.
Memory is an active process and not a disembodied store of information: remembering rather
than memory is happening. Three aspects to developing cognitive capabilities have been
mentioned: innate knowledge about some basics, powerful capabilities for learning, and social
structure allowing implicit tuition from other people.
The other two invited keynote speeches covered mechano-adaptive bone cell activities. Vincent
Everts gave an overview on "Cell Biology of Mechanoadaptive Bone Remodeling". Bones
2
adapt their mass and structure to the demands of mechanical usage. The remodeling cycle of
bones with their different cells of specialized functionalities has been described. The effects of
strain-induced fluid flow on cell activation may lead to predicting the long-term integration of
bone-replacing implants. – The presentation by Rommel G. Bacabac on "Rheology of
Mechanosensitive Bone Cells" elaborated further in more detail on the bone adaptation
processes. The bone is a dynamic, living tissue. Experimental and modeling results of bone cell
behavior and their mechanical properties have been explained.
The Leader of the COE Materials Group, Takayuki Kitamura, gave an "Overview of the
Researches of Complex Material Group". The two main research subjects of the group are biomechanics and nano-components. As bio-mechanics has been covered by the two succeeding
presentations (Tanaka, Adachi), Kitamura emphasized research works in nano-components
with explaining structures, experiments on stress and strain, and simulation.
The last two presentations dealt with bio-mechanics and built upon the two invited speeches on
mechano-biology of bone tissues (Everts, Bacabac). Mototsugu Tanaka talked about
"Mechanosensing Behavior of Cell Network System in Bone Tissue Matrix". The network
system formed by bone cells is considered as one of the important elements for bone
remodeling. It has been assumed that understanding the mechano-sensory mechanism of the
bone network system in detail may lead to the creation principle of smart composite materials.
– Finally, Taiji Adachi presented his research work on "Computational Modeling and
Simulation of Mechanobiology in Bone Functional Adaptation by Remodeling". The bone
network structure has been obtained from a uniform stress hypothesis at the cellular level. The
micro-mechanism in the mechano-sensory cell network leading to uniform stress has been
described.
In the closing session, comments from the Honorary Evaluator, Gunnar Johannsen, and from
all invited speakers on the success of the seminar were given. Further, concluding Remarks
were presented by the COE Project Leader, Kazuo Tsuchiya, and by the Seminar Organizers
(Tetsuo Sawaragi and Marek Makowski).
3. Evaluation of the Seminar
The scientific quality of the seminar was again of highest caliber compared with strong
international standards. This time, even all presentations were excellent in contents and style.
The preparations and efforts of the Japanese colleagues and, also, of the invited speakers were
admirable. The discussions were very fruitful, cooperative, and open-minded.
The scientific approaches and the application domains of the eight COE Program speakers of
Kyoto University and those of the five invited speakers were much more complementary than
in 2004. IIASA was not represented by any scientific presentation at this seminar.
This COE Program of Kyoto University can be congratulated to their visionary approach for
mechanical engineering with the strong emphasis on learning from biology, linguistics, and
cognitive sciences. Thereby, commonalities in functionalities and dynamical behaviors have
been discovered across all complex systems under investigation in both research fields of
material science and systems engineering. This is a great scientific progress compared with the
two previous years. The dedication, the excellent research results, and the research culture
achieved in the whole group of Kyoto University comprise strong potentials towards a leading
role of mechanical engineering research in the world.
3
海外との組織的な交流
京都大学‐ミシガン大学‐フライブルク大学 MicRO アライアンス
工学研究科マイクロエンジニアリング専攻
田畑 修
Abstract: The objective of this alliance between three Universities, Kyoto University, The University of Michigan and
Freiburg University, so called MicRO (Micigan, fReibuRg, kyOtO) alliance named after each Universities name, is the
establishment of new design and fabrication paradigms for micro electro mechanical systems (MEMS) of next-generation
in which nanostructures are integrated with MEMS. In 2006, the 3nd symposium was held on 6th – 7th July at Freiburg
University with about 100 participants.
Also the web site of the MicRO alliance was launched at
“http://portal.uni-freiburg.de/MicROalliance” from March 2007.
Key words: MEMS, Michigan, Freiburg, alliance, education
1. はじめに
2004年11月,京都大学,ミシガン大学,フライブルク大学の3大学は次世代微小電気機械融合システム
(MEMS: Micro Electro Mechanical Systems)分野の基盤技術の系統的構築を目指して,3大学の学術交
流協定を締結した.京都大学では多くの大学と学術交流協定が締結されているが,3大学による学術交流
協定の締結は初めてのケースである.この3大学はそれぞれアジア,欧州,北米におけるMEMS分野の研究
拠点として活躍しており,それぞれの大学の名称とこの研究分野からマイクロ(MicRO:Micigan,
fReibuRg, kyOtO)アライアンスと名付けられた.現在この学術交換協定に基づき,21世紀COE「動的機
能機械システムの数理モデルと設計論」による支援を受けて,毎年シンポジウムが開催されている.本
稿では平成17年度のMicROアライアンス活動内容について述べる.MicROアライアンスの目的と目標の詳
細,およびミシガン大学,フライブルク大学の概要と特徴は2004年度の報告書を参照して頂きたい.
2. シンポジウム
2004 年 11 月に京都大学で開催された第 1 回シンポジウム,2005 年 10 月 14 日にミシガン大学アナー
バーキャンパスで開催された第 2 回シンポジウムに引き続いて,第 2 回シンポジウムが 2006 年 7 月 6‐
7 日にフライブルク大学において約 100 名の参加者を得て開催された.京都大学からは教員 5 名,学生 3
名の計 8 名,フライブルク大学からは教員 4 名が参加した.シンポジウム初日には学生同士の交換会,
運営委員会,レセプションが開催され,2 日目にはシンポジウムが開催された.2 日目はマイクロシステ
ム工学科の修了式の日でもあったため,シンポジウムの最終講演は MicRO アライアンスと修了式が共催
する形式とし,ミシガン大学の Ken Wise 教授が“Wireless Integrated Micro Systems (WIMS): Coming
Revolution in the Gathering of Information”と題する講演をアライアンスメンバーと修了生合わせ
て 180 名の聴衆に対して行った.午前中からのシンポジウムでは,ミシガン大学から交際交流を含めた
ミシガン大学の教育・研究への取り組みが Pang 教授から紹介された後,Gianchandani 教授(ミシガン
大学)
,Rohrbach 助教授,Woias 教授(フライブルク大学)
,江利口助教授,土屋助教授(京都大学)か
らそれぞれの大学における研究紹介が行われた.シンポジウム終了後は,修了生と共にガーデンパーテ
ィーに参加し,大いに交流を深めることができた
運営委員会(写真 1)では,ミシガン大学とフライブルク大学の学生交換協定に調印し,協定が締結
された.学生交換協定で残っているのは京都大学とミシガン大学の協定である.留学費用負担について
の考え方や体制の相違からまだ締結の見通しは立っていないが,一刻も早期の締結が期待される.開催
され今後のアライアンス活動についての意見交換を行った.京大からの参加学生には,シンポジウム開
催期間前後にフライブルク大学に滞在してフライブルク大学学生との交流を深めることを強く奨励した.
その結果,2 名の学生が開催数日前からフライブルク大学に滞在し,研究室訪問などの貴重な経験をし
た.第 4 回シンポジウムは 2007 年 10 月 4‐5 日,京都大学において開催される予定である.
3. その他
平成 19 年 1 月に神戸において開催された第 20 回MEMS国際会議の最終日 25 日の午後,運営委員会(写
真2)を開催し,今後の活動について意見交換を行い,MicRO アライアンスを継続していくことで関係者が合意
した.ここれを受けて,2007 年秋に満了する 3 年間の研究交流協定期間をさらに延長することが満場一致で決
定された.また活動内容をさらに充実させるために MicRO アライアンスの専用Webページを開設すること,お
よび 共同研究テ ーマ を設定し,より積極的な研究連携を 図る こ とが合意さ れた .W ebペ ー ジ
( http://portal.uni-freiburg.de/MicROalliance )はフライブルク大学マイクロシステム工学科のサーバーに設置
され,稼動を開始した.今後,内容を充実させていき,それぞれの学生が留学するときのゲートウエーとしての
機能や,社会に向けての教育・研究活動の情報発信の機能を持たせていく予定である.
学費不徴収を含む学生交換協定がフライブルク大学-ミシガン大学,フライブルク大学-京都大学間で締
結されたことで,今後学生レベルの交流をますます活発化させる下地は整いつつあるが,残念な事は,京大か
ら協定大学へ行こうとする学生がまだ極めて少ないことである.京大の学生諸君もこの MicRO アライアンス協
定を利用して積極的に研究の舞台を世界に広げてもらいたいと熱望している.
写真1 2006年7月,運営会議出席メンバー
写真2 2007年1月,運営会議出席メンバー
京都大学-韓国科学技術院(KAIST)
Joint Workshop
報告者 工学研究科 機械理工学専攻
担当教員 工学研究科 機械理工学専攻
1.
嶋田 隆広
北村 隆行
はじめに
2004 年 5 月 20 日~23 日の 4 日間,京都大学と韓国科学技術院(Korea Advanced Institute of
Science and Technology : KAIST)は,両大学の機械系博士課程学生同士の研究発表および意見
交換,国際交流を目的とし,Kyoto Univ. and KAIST 1st Joint Workshop を行った.Seyoung Im
教授(KAIST)と北村隆行教授(京都大学)は,かねてより深い交流があり,今回,21 世紀 COE
プログラム「動的機能機械システムの数理モデルと設計論」-複雑系の科学による機械工
学の新たな展開-(京都大学側)と Center for Nano Scale Mechatronics & Manufacturing BK21
KAIST Valufacture Institute of Mechanical Engineering (KAIST 側)による支援を受け,第一回目
の Workshop 開催に至った.運営は博士課程学生が主体となり,KAIST 側は Sungjin Kwon
氏と Youngmin Lee 氏が,京都大学側は私がワークショップ代表者として活発な意見交換を
行い,スケジュールを決定した.ワークショップでは,京都大学から 9 人(北村研 6 人,宮
崎研 3 人),KAIST から 8 人の博士課程学生が 2 日間に渡って研究発表・意見交換を行った.
本報告では,ワークショップにおける研究発表だけでなく,学生交流の様子についても記
す.
2.
韓国訪問(ソウル-デジョン)
韓国は朝鮮半島の南半部に位置し,日本海を挟んで日本の隣国となっている.大阪
-Incheon 間は航空機で約 1 時間半程度と非常に近く,日本と類似の文化も多く見られる.5
月 20 日,関西国際空港から韓国 Incheon 空港へのフライトを経て,ソウルに到着した.韓
国の首都ソウルは人口約 1000 万人,面積約 600km2 の大都市であり,人口密度は世界一高
い都市と言われている.5 月 21 日には,ソウルより KAIST 本校のあるデジャンへと向かっ
た.KAIST に到着した我々は Im 教授および同研究室の学生に歓迎していただいた.夕食は
KAIST 内のレストランで学生も含め全員で韓国料理を頂いた(図 1).食事後は,私を含む運
営者同士がミーティングルームに集まり,翌日のワークショップのための準備や事前確認
などを行った.
図 1 歓談を愉しむ学生達
3.
Joint Workshop
韓国滞在 3 日目(5 月 22 日),Kyoto Univ. and KAIST 1st Joint Workshop が開催された
(図 2).本ワークショップのスケジュールを(資料1)として後に示す.ワークショップ一
日目は4セッション,二日目は2セッションから成り,1セッションにつき 3~4 人,京都
大学側と KAIST 側が交互に研究成果のプレゼンテーションを行った.ワークショップの進
行も学生が主体となって動き,各セッションの座長は博士課程学生が行い,KAIST2 名,京
都大学 2 名がそれぞれ担当した(図 3).プレゼンテーション 20 分,質疑応答 5 分で行い,
2 日間で 17 名の博士課程学生が発表を行った.研究内容は,連続体力学に基づく巨視的
な強度評価(シミュレーション)研究が3件,破壊力学(異方性材料の破壊力学,3次
元形状き裂の破壊力学など,報告者の発表含む)関連が5件,より微視的な強度評価の
領域(ひずみ勾配理論,転位論)が2件であり,他は量子力学を用いた機械的特性・強
度および物性の評価に関するものであった.
原子を扱ったシミュレーションでは,京都大学側は,量子力学に基づく第一原理解析を
用い,電子/原子レベルからの材料強度・物性の厳密な評価を行う研究が主となっていた.
一方,KAIST 側は,Al(111)表面のスクラッチシミュレーション,カーボンナノチューブ(CNT)
の生成やボンドの組換え過程の解明,多層 CNT 解析のための準連続体理論適用など大規模
解析に目を向けた研究が多く,計算時間短縮のための並列化に関する研究も同時に行われ
ていた.異なる視点からのアプローチのため,お互いに興味を引かれ合い,多くの質疑・
応答が行われた(図 4).また,ナノ~サブミクロンオーダーの材料の実験および FEM 解析に
よる強度評価が発表された.また,現理論の改善および新しい近似法の導入など解析手法
の発展に繋がる研究も行われていた.総じて,京都大学および KAIST の研究内容は,電子/
原子/ナノ/サブミクロンオーダーという広い範囲に渡っており(図 5),まさにマルチスケー
ルな視点から材料強度・物性を解明していく基幹的なものであると感じた.
図 2 ワークショップ
スケジュール
図 3 座長を務める学生
図 5 プレゼンテーションの様子
図 4 質疑応答の様子
ワークショップ4日目(5 月 23 日)の最終では,北村隆行教授より機械系博士課程学生へ
向けて教育的な意味を込めた講義をして頂いた.自分の立っている場所を明確にし,目的
を見つめ,そこに潜む基本的・根本的な概念を見つけ出すことが研究で最も必要であり,
かつ重要なことであるという示唆は,我々にとっても KAIST の学生にとっても良き道標と
なった.その講演を受ける形で,Im 教授から今回のワークショップの成功と次回開催の誓
いがあり,閉会となった(図 6).
その後,簡単な昼食を取りながら,学生同士お互いの連絡先を交換した.何人かの学生
は互いの論文を交換している様子もあった.KAIST を後にした我々は,その日の午後の便
で帰国した.
4.
Kyoto Univ. and KAIST 1st Joint Workshop 参加者アンケート
今回のワークショップのよかった点・反省点を明確にし,次回ワークショップをよりよ
きものにするために,京都大学側からの参加者全員にアンケートを行った.アンケートの
結果を(資料2)として,後に添付する.
アンケート結果を簡単に総括する.英語でのプレゼンテーションの経験のある学生は少
なくはないものの,その回数は数回にとどまっている.今回の企画はまさに,英語での発
表の機会を与えるものであり,本 Workshop を通じて各々がよい経験であったとしている.
また,発表を通じて,良かった点だけでなく問題点を見つけることができたようであり,
大きな刺激になったようである.これらから、学生のこれからの国際的な研究活動特を促
進する効果があったと思われる.とくに,英語によるコミュニケーションは国際的な研究
者となる上で,必要不可欠なものであり,その重要性を再認識したという声も多かった.
一方,Workshop の改善点として,十分な質疑応答時間をとることやアブストラクトの作成,
研究設備見学といったツアーを盛り込む必要があることなどがあげられている.今回の
Workshop の運営者として,これらの意見を真に受け止め,次回の成功に繋げたいと思う所
存である.
図 6 閉会式
(資料1:プレゼンテーションスケジュール)
Kyoto Univ.- KAIST Joint Workshop
On Nano-mechanics and Nano-technology
(May 20-23, 2006)
Presentation Schedule (May 22~23, 2006 )
May 22( Monday ), 2006
Time
Speaker
08:50 ~ 09:10
Title
Room
Opening
E1 Seminar Room
Stress intensity factor analysis of three-Dimensional
Masataka
interface crack between dissimilar anisotropic mat
Nagai
erials
09:10 ~ 10:50
(Youngmin Lee)
Shin,
Hyoyoung
Shuji
Takashima
Sungjjin
Kwon
10:50 ~ 11:00
~ 12:15
(Yoshimasa
the method of domain field projection
E1 Seminar Room
Study of Hall-Petch effect from the point of view
of plastic strain gradient
Parallel computation of large-scale molecular dyna
mics simulations
break time
Nobuyuki
11:00
The view of screw dislocation core structure using
Strain measurement in the micro-structure of electr
Shishido
onic packages using digital image correlation
Kanghyouk
Large-scale finite element analysis of welding proc
Choi
Takahashi)
esses
E1 Seminar Room
Effect of Loading Frequency on Fracture Crack Gr
Do Van
owth between
Truong
Submicron-Film and Substrate
12:15 ~ 13:40
Lunch
13:40 ~ 15:20
Jeewon
Fist-principle calculations of adsorption structure an
(Sungjin Kwon)
Kang
d energies for alkanethiols on the Au(111) surface
Akihiro
Kushima
Faculty House Caf
eteria
E1 Seminar Room
First Principles Evalution of Ideal Strength of Si
Nano-film
Youngmin
Large scale simulations of scratching on the (111)
Lee
surface of thin Al films
Yoshimasa
In situ TEM observation of interfacial fracture in
Takahashi
nano-scale dissimilar body
15:20 ~ 15:30
break time
Effect of microstructural inhomogeneity on fatigue
Masato
crack propagation property of directionally solidifie
Yamamoto
d superalloy
15:30 ~ 17:10
(Masaki Nagai)
Sung Youb
A Microscopic Merging Process of Carbon Nanotu
Kim
Yusuke
bes
First-principles study on elastic anomalies in Ag/Al
Kinoshita
Jong Youn
E1 Seminar Room
multilayers
A quasicontinuum method for deformations of carb
Park
orn nanotubes
May 23( Tuesday ), 2006
Time
Speaker
Title
place
High throughput Nanoimprint Lithography
E1 Seminar Room
Dr. Eung-Sug Lee
09:00 ~ 09:40
(Invited Speaker:
KIMM)
Multi-physics analysis of perovskite
Takahiro Shimada
E1 Seminar Room
surface; ab initio study
09:40 ~ 10:30
MLS(Moving Least Square)-based finite ele
(S. Im)
Jae Hyuk Im
ments for non-matching meshes and contact
E1 Seminar Room
problems
10:30 ~ 10:40
break time
Education of nanoengineering for
10:40 ~ 11:10
Prof. Kitamura
E1 Seminar Room
Mechanical engineering students
11:10 ~ 11:30
Prof.Kitamura
Closing remarks
Prof. Im
Photo
* Presentation Time ( each person )
: 25 minutes ( talk : 20 minute, questions :5 minutes )
E1 Seminar Room
(資料2:アンケート結果)
(1) プレゼンテーションは将来に向けて良い経験になりましたか?
(1~5の5段階評価,
平均
良い:5
4
3
2
1:悪い)
4.8
(2) ディスカッションには参加しましたか?
はい・・・100%,
いいえ・・・0%
・参加した感想
学生が多いので参加しやすい雰囲気であった./ 勉強になりました.
There are useful questions for my study.
最初に質問しても,それ以降,英語力の不足もあってディスカッションを深める
ことが難しかった./ 出来ればもっと質問したかったが,英語力のなさからあまり
質問することができなかった./ 英語で詳細に説明することが難しかった.
(3) KAIST の学生さんとはコミュニケーションができましたか?
(1~5の5段階評価,
平均
とても良くできた:5
4
3
2
1:できなかった)
4.2
(4) ドクターコースの教育課程として,このような企画は良いと思いますか?
(1~5の5段階評価,
平均
良い:5
4
3
2
1:悪い)
5.0
(5) 今回の企画について感想があれば書いてください.
・ 海外の自分たちと同じ立場の学生と交流を持つことは,学術的な面だけでなく,
互いの文化を理解するきっかけになり,有意義なものであったと思う.
・ 適度な発表時間で韓国と日本の両者の発表を行うことで,研究の内容議論のみな
らず,両国の研究/教育に対するスタンスの共通点や相違点を体感することができ,
非常に有意義であったと思います.総じて,京大側の研究は創意工夫によって学
術分野の深化を目指す傾向にあり,KAIST 側は現実世界への応用/適用を目指す
傾向にあると感じました.いずれも重要な方向性であり,バランスが重要である
と感じました.また,同年代の研究者と緊密にコミュニケーションすることで,
互いの理解を深めることができたと思います.
・ 英語でのコミュニケーションに問題が無い人は別として,ほとんどの人にとって,
今回の企画での一番の難関は英語であったと思う.今回の企画で,英語でコミュ
ニケーションすることへの恐怖心が和らいだように思う.
sann
Kyoto Univ. – KAIST Joint Workshop
on Vibration Control Engineering
工学研究科
1.
精密工学専攻
山田 啓介,奥山 智尚
はじめに
2006 年 8 月 31 日から 9 月 1 日の 2 日間,京都大学と韓国科学技術院(Korea Advanced Institute of Science
and Technology,以下 KAIST)の振動工学研究室の博士課程の学生を中心に,研究に関する意見交換と
両大学の学生間の交流を目的として第 1 回 Joint Workshop を KAIST(韓国,Daejeon)において開催した.
ただし,京都大学側は京都大学の学生に限定せず,京都府内の他大学にも声をかけ,同志社大学からも
博士課程の学生が 1 名参加した.Joint Workshop の計画・運営は両国の博士課程の学生が協力して行っ
た.ただし,京都大学の松久寛教授と KAIST の Chong-Won Lee 教授の協力を得て開催に至ったという
ことを合わせて記しておく.日本側は京都大学から 5 名(松久研 4 名,市川研 1 名),同志社大学から 1
名(小泉・辻内研)の合計 6 名が,韓国側は KAIST から 6 名(Lee 研 4 名,Park 研 2 名)が参加し,英
語で研究発表と意見交換を行った.本 Joint Workshop の目的は,両国間の研究に関する情報の交換や英
語によるプレゼンテーションの訓練にとどまらず,Workshop の企画と運営の経験を積み,その過程も含
めて両国の学生達が交流し,お互いの文化を学ぶことにもある.そこで,本報告書では Workshop と両
国の学生の交流の両方について述べる.
なお,京都大学から本 Workshop に参加した 5 人の学生は,21 世紀 COE プログラム「動的機能機械シ
ステムの数理モデルと設計論」-複雑系の科学による機械工学の新たな展開-の助成を受けたことを付
記し,謝意を表する.
2.
Joint Workshop
8 月 31 日,Kyoto Univ. and KAIST Joint Workshop on Vibration Control Engineering が開催された.本
Workshop のスケジュールを資料として後に示す.Workshop は 4 セッションからなり,1 セッションに
付き 3 名ずつ,日本側 6 名と KAIST 側 6 名の博士課程学生が交互に研究成果のプレゼンテーションを
行った.開会スピーチは KAIST の Lee 教授と京都大学の宇津野助教授が行ったが,全体の進行は学生
により執り行われた.各セッションの座長は学生が行い,KAIST2 名,日本側は京都大学 2 名がそれぞ
れ担当した(図 1).各発表者の割り当て時間はプレゼンテーション 20 分,質疑応答 5 分だった.また,
本 Workshop では 5 月に COE の支援の元で行われた他分野の研究室同士の Workshop の反省を踏まえ,
前もって発表内容のアブストラクトを作成し,参加者に配布した.
研究内容は,「Vibration Control」の名の通りダンパ・板や梁および軸構造物の振動解析と制御が主で
あったが,それらに留まらない多様な発表が行われた(図 2).ダンパについては,
「Variable damping and
stiffness vibration system with two controllable dampers(京大)」と「Reducing Floor Impact Vibration and Sound
Using A Momentum Exchange Impact Damper(京大)
」の数値計算及び模型実験結果が発表された.構造物
の振動解析としては,「Dynamic response of golf club and sensor module development for virtual club fitting
equipment(KAIST)」,「Extended Layout of Stiffeners to Increase Fundamental Frequency of Shell Structures
(KAIST)」,
「Modal Model Reduction for Vibration Control of Flexible Rotor(KAIST)」の発表があり,実
際の製品開発を視野に入れた数値計算法の改良が示された.また KAIST 側による「Design of the
electromagnetic actuator with permanent magnet for the high efficiency and small size」と,「Low-cost Hybrid
Active Magnetic Bearing with Hall Diodes used as Proximity Probes」で発表された実験機は,製品のプロト
タイプとして高い完成度を持つものであり,KAIST における振動制御研究室の産業界との強い結びつき
を感じさせるものだった.これら以外にも「Precise measurement technique of the electromechanical coupling
coefficient of piezoelectric elements(京大)」および「Longitudinal acceleration wave decomposition in time
domain with single point axial strain and acceleration measurements(KAIST)」では測定における新手法の基
本原理が提示され,振動からやや離れた「Acquisition of slip phenomenon for developed distributed-type force
sensor(同志社)」
,「Prediction of the measured sound pressure of traffic noise using interpolation of the transfer
function(京大)」
,
「Adaptive Output Regulation for Linear Systems(京大)」の研究が日本側から発表され,
自分達とはやや異質の研究対象に対し KAIST 側の学生達が興味を示す様子が伺われた(図 3).
午前のセッション終了後,食堂で日韓の学生が入り混じって昼食をとった.食事中,学業に限らない
普段の生活などに関する会話が学生間で交わされ,それぞれの環境で研究生活にいそしむ互いの姿を等
身大で捉えながら,より親睦を深めることができた.昼食後は KAIST の研究室見学となり,学生達の
共同部屋と実験室を見て回った(図 4).実験室には Workshop の発表にあったもの以外にも多数の実験
機が置かれ,中には実際に企業で製品化される段階に近い部品などもあって,産業界との太い繋がりを
裏付けていた.
全てのセッションが終了した後,Lee 教授が閉会の挨拶をされ,参加者全員で校庭に移動して記念写
真を撮影した(図 5).
図 1 座長を務める学生
図 3 質疑応答の様子
3.
図 2 プレゼンテーションの様子
図4
KAIST の実験室
図 5 記念撮影
交流会
Joint Workshop が開催された 8 月 31 日は KAIST の夏季休暇の最終日で,夕方から機械工学専攻の建
物の中庭で専攻を挙げてのパーティーが催された.日本から Joint Workshop に参加した 7 人もそのパー
ティーに招待していただき,韓国の学生達と歓談を楽しんだ.このパーティーは KAIST の機械工学専
攻で近年始まったもので,学部生から博士課程の学生,教員までが自由に参加できる.パーティーでは
成績優秀者の表彰や,留学生による催し物などがなされ,途中で日本から参加した我々7 人も紹介され
た.KAIST の留学生の出身国は中国等のアジアが多く,少数のヨーロッパ人もいるということだったが,
日本人留学生はほとんどいないとのことだった.逆に KAIST の学生が日本に短期留学することはあり,
今回の Joint Workshop で韓国学生側の代表だった Jeon さんも昨年の夏季休暇中に日本大学に短期留学し
たとのことだった.パーティー終了後,場所を変えてさらに歓談を楽しんだ.日本側参加者のうち 2 人
は中国人とインドネシア人だったので,4 国の文化や歴史,大学のシステムの相違について話し合った
り,研究室生活を説明し合ったりした.
図6
KAIST で催されたパーティーでの様子
Joint Workshop の翌日の 9 月 1 日,
韓国人学生の Jeon さんと Seo さんの案内でソウル市内を散策した.
KAIST のあるデジョンからソウルまでは KTX(新幹線のようなもの)で 50 分程度であり,料金は 19000
ウォンと非常に安かった.ソウルでは景福宮を見学し,インサドンを経て,ソウルタワーに登った.市
内の看板はほとんどがハングルで書かれているため日本人には理解できないが,2 人の説明のおかげで
困ることはなかった.韓国では日本食,日本映画,日本の漫画・アニメ等の人気が高いことが街を散策
しているだけでもよく分かった.
図 7 ソウル市を案内していただいた
最後に KAIST について簡単に紹介する.韓国政府は人材育成と科学技術の発展の主導的役割を果た
す研究機関の設立を計画し,1971 年,韓国初の政府援助による,科学技術分野のみを専門とする大学院
として KAIST を設立した.KAIST は大学新入生 500 人の 8 割が高 2 からの飛び級入学(高 3 の 1 年間
を入試に当てるのは時間の無駄という発想より)で,無学科,無学年で能力に応じて卒業できる学費無
料の全寮制大学であり,大学院生の中には優秀な研究成果によって兵役免除の学生も多く存在する.韓
国で唯一の科学技術省傘下の大学であり,日本と同様に資源の乏しい韓国の,人材育成によって経済的
な競争力をつけるという国策の一つである.現在では KAIST の卒業生が科学技術系の大手企業に多数
採用され,韓国の経済を牽引している.
4.
おわりに
こうして京大・KAIST 双方の振動制御研究室を中心とした Joint Workshop は無事に終了した.以下に
今回の感想および意見を述べる.
博士課程においても学生の国際的舞台での発表の機会は多くはなく,英語によるプレゼンテーション
の経験を積む上でこの Joint Workshop は有意義なものであった.今回の発表を通じて,国際的に研究活
動する上での英語力の重要さを留学経験のない学生たちは特に実感し,また自分の研究に対する別の視
点からの意見・質問を受け,問題を多面的に捉える姿勢が鍛えられた.また,発表会だけでなく昼食や
発表後の交流会により他国の学生達と対等な立場で親睦と理解を深めたことは,参加者の世界観を広げ
るだけでなく今後の研究生活における国際的な人脈を構築する礎となり,日韓両国の産学にとって有益
であると思われる.
今回の Workshop では質疑応答の時間を 5 分としたが,活発な議論のために 10 分にすべきではないか
という意見もあった.そこで,時間をオーバーしても議論が続いている場合は,質疑応答を打ち切らな
かった.しかし,議論が英語力のある少数の人間中心に行われたことも事実である.また,英語力の問
題で深い議論をできない場面が何度か見受けられた.こ
のような Joint Workshop はそれ単独ではなく,学生達の国際コミュニケーション能力を上げるような基
礎があってこそ初めて真価を発揮すると思われる.KAIST では教科書が全て英語で,授業の 3~4 割が
英語で行われているといい,実際に彼らの英語力は日本側の学生を上回るものであった.この事実を踏
まえ,日本でも学生達の英語力を上げるようなカリキュラムを学部生の段階から積極的に増やしていく
べきだと提言したい.
以上の感想および意見が次回のさらなる成功へと繋がれば幸いである.
Kyoto University – KAIST Joint workshop
On Vibration Control Engineering
August 31, 2006
Seminar Rm. E1
Mechanical Engineering Building, KAIST, Korea
Presentation Schedule
Time
Chair
Speaker
08:50 ~ 09:10
09:10 ~ 10:25
Han-Wook Jeon
Opening
Akihito Ito
Acquisition of slip phenomenon for developed
(Doshisha Univ.)
distributed-type force sensor
Joonkeol Song
Dynamic response of golf club and sensor module
(KAIST)
development for virtual club fitting equipment
Tomonao
Prediction of the measured sound pressure of
Okuyama
traffic noise using interpolation of the transfer
(Koyto Univ.)
function
10:25~10:55
10:55~12:10
Mai Bando
Coffee Break
Ok-Hyun Kang
Extended layout of stiffeners to increase
(KAIST)
fundamental frequency of shell structures
Keisuke Yamada
(Kyoto Univ.)
Byungbo Jung
(KAIST)
12:10 ~ 13:40
Title
Precise measurement technique of the
electromechanical coupling coefficient of
piezoelectric elements
Longitudinal acceleration wave decomposition in
time domain with single point axial strain and
acceleration measurements
Lunch Break
13:40 ~ 14:55
Joonkeol Song
Han-Wook Jeon
Modal Model Reduction for Vibration Control of
(KAIST)
Flexible Rotor
Yanqing Liu
Variable damping and stiffness vibration system
(Kyoto Univ)
with two controllable dampers
Bo-Ha Lee
(KAIST)
14:55 ~ 15:25
Design of the electromagnetic actuator with
permanent magnet for the high efficiency and
small size
Coffee Break
Mai Bando
(Kyoto Univ.)
Adaptive Output Regulation for Linear Systems
15:25 ~ 16:40
Sang-Hyun Park
Low-cost Hybrid Active Magnetic Bearing with
Keisuke Yamada
(KAIST)
Hall Diodes used as Proximity Probes
Lovely Son
Reducing floor impact vibration and sound using
(Kyoto Univ.)
a momentum exchange impact damper
16:40 ~ 17:00
Closing remarks
Photo Taking
17:00 ~ 17:45
NOVIC Lab Tour
17:45 ~ 21:00
Banquet
** Twenty minutes for presentation and five minutes for question and
comments will be given
September 1, 2006
Tour Schedule
Time
Schedule
Expense(Won)
09:00
Leaving Dae-jeon for Seoul by KTX
19000
11:30
Check in New Oriental Hotel
11:30 ~ 12:30
Lunch
12:30 ~ 16:30
Visiting National Museum of Korea
16:30 ~ 18:00
Looking around In-Sa dong
18:00 ~ 19:00
Dinner
19:00 ~ 21:00
Looking around Myung dong
21:00 ~ 22:30
Visiting Nam-san tower
3000
5000
Acquisition of Slip Phenomenon for Developed
Distributed-type Force Sensor
Akihito Ito
Dept. of Mechanical Eng, Doshisha University
[email protected]
Abstract
At present, robots are expected to extend their range of activities to not only
industry but also to care and welfare apparatuses, such as care robots that handle
advanced tasks. Concurrent with the expansion of robots' application field, the
requests for tactile sensors have also been increasing. Though research and
development of various tactile sensors have been carried out until now, the practical
sensor has not been completed yet. To accomplish practical tactile sensors, it is
necessary to acquire forces and moments acting on the fingertips of the robot hand,
and in addition, it is necessary to detect the slip. Especially, evaluation of relative
movements between the sensor and the contacting object is indispensable when
detecting slip. Thus, the force acting on the fingertips of the robot hand needs to be
measured as distribution of forces in the direction of three axes. In our previous
study, we proposed a distributed-type tactile sensor having 12 sensor elements,
each of them able to detect vertical force and shear force, arranged in the 15 mm
20 mm area on the same plane. The prototype sensor, five times larger than those to
be used in practice, was developed, and the algorithm for evaluating relative
movements between the sensors and the contacting object was completed.
However, the slip is divided into micro slip and macro slip. Micro slip appears in
the initial state of slip, and then, by the expansion of micro slip it becomes the
macroscopic slip, namely the relative slip between contacting object and sensor.
Micro slip and macro slip are the phenomena that occur continuously, and by
detecting micro slip, it is possible to predict macro slip.
In this paper, we present a method for detecting micro slip. Micro slip is
detectable from the vibration information of output value of strain gauge attached
on the surface of sensor elements. From the experiment, we showed that micro slip
is detectable using the slip information trained in advance. Since this sensor can
detect both of the macro and micro slip, it is possible to construct a sensor system
robust to slip.
Dynamic response of golf club and sensor module development for
virtual club fitting equipment
Joonkeol Song and Chong-Won Lee
Center for Noise and Vibration Control (NOVIC), Dept. of Mechanical Eng.,
KAIST, Science Town, Daejeon, KOREA
[email protected]; [email protected]
Abstract
Club fitting is one of best ways to improve your performance without hard time of
practice. Many club fitting methods have been suggested and some are employed.
However most of them require very expensive equipments and good instinct of
clubmakers. This research proposes the cost effective and automatable way. With 6
DoF sensor signals attach to the club, the motion, deflection and torsion can be
calculated and it imparts perfect information for this purpose. In this paper, the
developing 6 DoF sensor module will be introduced and the basic simulation results
for golf club’s deflection response for base excitement will be presented.
KEYWORDS: golf, club fitting, cantilever beam
Prediction of the measured sound pressure of traffic noise
using interpolation of the transfer function
Tomonao OKUYAMA 1, Hiroshi MATSUHISA 2, Hideo UTSUNO 3 and PARK Jeong
Gyu 4
1
Department of Precision Engineering, Kyoto University
Yoshida-Honmachi, Sakyo-ku, Kyoto, 606-8501, Japan
e-mail: [email protected]
2
e-mail: [email protected]
3
e-mail: [email protected]
4
e-mail: [email protected]
Abstract
When a new high way road is planning, traffic noise will be predicted through the
scale model experiment before the construction. In this study, the method to
calculate the sound pressure at the evaluation point from the moving source is
proposed. The proposed method discusses an interpolation method of measured
transfer functions at several points on the road model. There are some paths from
the sound source to the evaluation point, and the transfer function is expressed
theoretically as the function of each path length and each diffraction and reflection
coefficients. The impulse response obtained from measured transfer function
consists of superposition of impulse response for each path. Comparing the
impulse response with theoretical one, each sound path can be separated and each
coefficient of the sound path can be identified. Using the identified coefficients
and path lengths, transfer function at an arbitrary point between the measured
points can be interpolated. From the digital sampled sound pressure at
neighborhood of the moving source and each interpolated transfer function at the
position of the moving source at each time, the sound pressure at the evaluation
point is obtained in the frequency domain. By Inverse Discrete Fourier
Transformation (IDFT), the sound pressure in the time domain can be derived. In
this method, only once IDFT is required.
Extended Layout of Stiffeners to Increase Fundamental
Frequency of Shell Structures
Ok-Hyun Kang , Youn-Sik Park, Young-Jin Park
Korea Advanced Institute of Science and Technology, Daejeon, Korea
[email protected]; [email protected]; [email protected]
Abstract
Structural Dynamics Modification (SDM) is to improve dynamic characteristics of
a structure, more specifically of a base structure, by adding or deleting auxiliary
(modifying) structures. In this paper, the focus will be concentrated on the optimal
layout of the stiffeners which are attached to the plate to maximize 1st natural
frequency. Recently, a new topology method was proposed by yamazaki. He uses
growing and branching tree model. In this paper, to overcome limitations of the
method, modified tree model will be suggested. To expand the layout of stiffeners,
non-matching problem will be considered. The problem is solved by using local
lagrange multiplier without the mesh regeneration. Moreover CMS(Component
mode synthesis) method is employed to reduce the computing time of eigen
reanalysis using reduced component models.
Precise Measurement Technique of the Electromechanical
Coupling Coefficient of Piezoelectric Elements
Keisuke YAMADA*, Hiroshi MATSUHISA**, Hideo UTSUNO** and Jeong Gyu PARK***
*Department of Precision Engineering, Kyoto University, Yoshida-honmachi, Sakyo-ku,
Kyoto 606-8501, Japan, JSPS Research Fellow
**Department of Mechanical Engineering and Science, Kyoto University, Kyoto, Japan
***LG Electronics Inc., 19-1 Cheongho-ri, Jinwuy-myun, Pyungtaek-si, Kyunggi-do, 451-713, Korea
[email protected]; [email protected];
[email protected]; [email protected]
Abstract
This paper describes a new precise technique for measuring the electromechanical
coupling coefficient of piezoelectric elements. Knowing piezoelectric elements’
precise electromechanical coupling coefficient is necessary for estimating their
performance and determining the optimum design of active vibration control and
the passive vibration suppression systems that use piezoelectric elements. The
electromechanical coupling coefficient can be derived using theoretical
formulations, however, simulation results using those values usually do not agree
well with experimental results. Therefore, it is much more favorable to
experimentally measure the electromechanical coupling coefficient. However, the
precision of conventional methods is not sufficient for some applications. This is
particularly true when the difference between natural frequencies is too small to
achieve good precision. For these reasons, a measurement technique that is less
sensitive to error in the measuring apparatus is required. In this paper, a new
method using resonance frequencies when an inductance is coupled to the
piezoelectric element was proposed. By using this method, the difference between
resonance frequencies becomes large enough to precisely determine the
electromechanical coupling coefficient. The effectiveness of the new method was
validated in experiment.
Longitudinal acceleration wave decomposition in time domain with
single point axial strain and acceleration measurements
Byungbo Jung , Youn-Sik Park, Young-Jin Park
Korea Advanced Institute of Science and Technology, Daejeon, Korea
[email protected]; [email protected]; [email protected]
Abstract
We investigated a longitudinal acceleration wave decomposition method in time
domain. The proposed method is useful to separate up- and down-stream
acceleration waves with an axial strain and axial acceleration measured at a single
point on the 1 dimensional transmission paths. The advantages such as low
computation load and easy implementation would be accomplished by the extension
to time domain under the assumptions; low frequency range, uniform cross
sectional area and elastic wave propagation. We confirmed the feasibility and
performance of the method through experiment using Split Hopkinson Pressure Bar
(SHPB). The method can be effective in several applications, including active
vibration power control, where wave separation should be obtained in real time.
Modal Model Reduction for Vibration Control of Flexible Rotor
Han-Wook Jeon and Chong-Won Lee
Center for Noise and Vibration Control (NOVIC), Dept. of Mechanical Eng.,
KAIST, Science Town, Daejeon, KOREA
[email protected]; [email protected]
Abstract
Nowadays, flywheel system is well know for energy storage system, and active
magnetic bearings are adopted due to low energy loss and so on. For the efficiency
of energy storage, the flywheel system is operated at very high speed and have large
polar moment of inertia. Therefore, flexible vibration among the vibration modes
and rotational speed dependent dynamic characterstics should be considered to
control the system safely. Moreover operation condition of rapid rotational
variation during the charge and discharge also should be considered for safe control.
FEM model that are used for vibration analysis is not appropriate for the control
model because of its large degree-of-freedom. Therefore this study proposes modal
approach to reduce the size of the control model instead of FEM model. Morever
the study proposes the simple polinomical fitting method to describe the
speed-dependent dynamics and modal truncation method via residue value
evaluation on the modal equation of motion.
KEYWORDS: model reduction, flywheel system, flexible vibration control
Variable damping and stiffness vibration system
with two controllable dampers
Yanqing LIU, Hiroshi MATSUHISA, Hideo UTSUNO
Department of Mechanical Engineering and Science, Kyoto University
Sakyo-ku, Kyoto city 606-8501, Japan, JSPS Research Fellow
[email protected]
Abstract
Semi-active systems with variable damping and stiffness have demonstrated
excellent performance. However, conventional devices for controlling variable
stiffness are typically complicated and difficult to implement in most applications.
To address this issue, a new configuration that requires two controllable dampers is
proposed. A controllable damper and a constant spring comprise a Voigt element.
The Voigt element and a spring are in series. This paper presents theoretical and
experimental analyses of the proposed system. The stiffness of the net system is
changed by controlling the damper in the Voigt element, and the other damper
provides variable damping for the system. The proposed system is experimentally
implemented using two magnetorheological (MR) fluid dampers. The experimental
results agree well with the theoretical analyses. Six different control schemes
involving soft spring, low damping, high damping, damping on-off, stiffness on-off,
and damping and stiffness on-off control are explored. The responses of the system
to sinusoidal and random excitations show that the variable damping and stiffness
control can be realized by the proposed system. Moreover, the system with damping
and stiffness on-off control provides good vibration isolation.
Design of the Electromagnetic Actuator with Permanent Magnet for
the High Efficiency and Small Size
Bo-Ha Lee and Chong-Won Lee
Korea Advanced Institute of Science and Technology, Daejeon, Korea
[email protected]; [email protected]
Abstract
As a dynamic actuator for attenuating the engine-induced vibration transmitted to passenger
vehicle chassis or investigating the vibration transfer path of the vehicle, an electromagnetic
actuator, consisted of a runner, two stators and pairs of electromagnets and permanent magnets,
is developed. It features that it is compact to be fit into the limited space and yet, it possesses
high efficiency and wide frequency bandwidth for effective control of engine vibrations in
standard size passenger cars.
By using the permanent magnets in electromagnetic system, we can increase the actuating force
of the electromagnetic system and decrease the total amount of the power consumption of
actuator when it operates. In addition to that an electronic circuit device is also developed such
that the displacement between the electromagnet pair and the target can be estimated from
measurement of flux density of the installed permanent magnet only. It is found that the
resolution and frequency bandwidth of the displacement estimator are about 3 m and 0 to 4kHz,
respectively.
The designed electromagnetic actuator is capable of attenuating the vibration over the frequency
range of 100 to 400Hz, which is satisfactory for applications of interest
Adaptive Output Regulation for Linear Systems
Mai Bando and Akira Ichikawa
Graduate School of Engineering, Kyoto University,
Yoshida-honmachi, Sakyo-ku, Kyoto, 606-8501, Japan
Abstract
In this paper, we consider the output regulation problem for linear time-invariant
systems with unknown parameters. First we consider the stabilization problem of
time-invariant system with unknown parameters.
We introduce an estimator of the system and adaptive laws which decrease the
estimation error of the state and parameters. We then introduce a feedback law
based on an algebraic Riccati equation. We give a sufficient condition for the global
asymptotic stability of the closed-loop system. We then consider the output
regulation problem and give sufficient conditions for solvability in terms of the
regulator equation. To relax the condition on the solution of the Riccati equation
imposed above, we introduce normalized adaptive laws. Using the solutions of the
Riccati equation and regulator equation we show that the some feedback law fulfills
the output regulation.
An example is worked out numerically and a simulation result of the tracking of a
sine function is presented.
Low-cost Hybrid Active Magnetic Bearing
with Hall Diodes used as Proximity Probes
Sang-Hyun Park & Chong-Won Lee
Korea Advanced Institute of Science and Technology, Daejeon, Korea
[email protected]; [email protected]
Abstract
Recently, design of low-cost miniaturized active magnetic bearings (AMBs)
becomes important. For lower power consumption, a novel design of small-sized
hybrid type AMB is proposed. The proposed 3- pole’s configuration requires fewer
number of power amplifiers compared to a conventional 4-pole AMB. But it has
heavy nonlinear properties in the magnetic flux between magnetic poles, and exists
coupling effect, which leads to non-linearity both states and control inputs. So it is
hard to make simple controller in general. In this paper, the redundant coordinates
to construct the identical controller are introduced. Also permanent magnets are
implemented to provide a constant bias flux, so that stator windings generate only
control flux to stabilize the bearing. In addition, instead of extra proximity probes,
three Hall diodes are used for the rotor displacement measurement, which reduces
the cost. And the experimental results showed the feasibility of the proposed AMB.
KEYWORDS: Active magnetic bearing, Redundant coordinates, Hall sensor
Reducing Floor Impact Vibration and Sound Using
A Momentum Exchange Impact Damper
Lovely Son*, Hiroshi MATSUHISA**, Hideo UTSUNO** and Jeong Gyu PARK***
*Department of Precision Engineering, Kyoto University, Yoshida-honmachi, Sakyo-ku,
Kyoto 606-8501, Japan
**Department of Mechanical Engineering and Science, Kyoto University, Kyoto, Japan
***LG Electronics Inc., 19-1 Cheongho-ri, Jinwuy-myun, Pyungtaek-si, Kyunggi-do, 451-713, Korea
[email protected]; [email protected];
[email protected]; [email protected]
Abstract
This paper deals with reducing floor impact vibration and sound by using a
momentum exchange impact damper. The impact damper consists of a spring
supporting a mass that is contact with the floor. When a falling object collides with
the floor, the floor interacts with the damper mass and the momentum of the falling
object is transferred to the damper. In this works a computational model is
formulated to simulate dynamic floor vibration induced by impact. The floor
vibration is simulated for various sized damper masses. A proof-of-concept
experimental apparatus was fabricated to represent a floor with an impact damper.
This example system consists of an acrylic plate, a tennis ball for falling object, and
an impact damper. A comparison between simulated and experimental results were
in good agreement in suggesting that the proposed impact damper is effective at
reducing floor impact vibration and sound by 25% and 63%, respectively
KEYWORDS: Impact Control, Flooring System, Momentum Exchange Impact
damper