論文 - 仰木　裕嗣

動作を計測するためのセンサ技術とその応用 センサ情報から身体動作を判別する

仰木 裕嗣

バイオメカニクス研究 19 （ 4 ） 249 - 255 2016年03月

力学解析による義足の調整方法および,セルフリハビリテーション方法の基盤開発

仰木 裕嗣富永修一

立石科学技術振興財団助成研究成果集 25   63 - 66 2016年01月

視覚障がいスイマーのためのトレーニング支援装置の開発

仰木 裕嗣谷川哲朗, 小林真, 鈴木完爾, 塚本昂佑, 山本明, 野崎基範, 寺田雅裕, 生田泰志, 野口智博

日本機械学会シンポジウム:スポーツ工学・ヒューマンダイナミクス講演論文集(CD-ROM) 2016   ROMBUNNO.A-2 2016年

ゴルフスイング中のグリップに作用する左右6分力計測と力の作用点推定

仰木 裕嗣太田憲, 有田大作

日本機械学会シンポジウム:スポーツ工学・ヒューマンダイナミクス講演論文集(CD-ROM) 2016   ROMBUNNO.A-33 2016年

Development of an automated motion evaluation system from wearable sensor devices for ski jumping

Heike Brock, Yuji Ohgi, Kazuya Seo

ENGINEERING OF SPORT 11 （ELSEVIER SCIENCE BV）  147   694 - 699 2016年

査読有り,  ISSN  1877-7058

　概要を見る

We developed a system for the automatic evaluation of ski jumps on the base of machine learning algorithms. In several capture sessions during summer jump season, motions of four junior ski jumpers were captured by inertial sensors over the complete jump, from the start of the in-run to the end of the outrun phase. Additionally, style points were collected from an experienced judge to serve as ground truth and control data for the machine learning algorithms. All jumps were randomly separated into a training and a test database. Next, we determined kinematic factors such as body segment orientation and body joint position and segmented every jump into its main motion phases on the base of the raw sensor data. Specific motion characteristics that influence the performance and length of a jump were then used to create machine style knowledge from the training database in compliance to the official scoring guidelines. In a last step, we computed the similarity of every jump within the test database to the trained knowledge on a ski jump's style parameters and evaluated the presence or absence of jump errors. Results showed that the computed error annotations conform largely to the human-based judging scores. Adding automatic score measures to the algorithm in future, this method might be an important step towards better measurability and objectivity of performance-oriented sports in form of a mobile competition evaluation system. (C) 2016 The Authors. Published by Elsevier Ltd.

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Design Optimization of the Landing Slope of a Ski Jumping Hill

Kazuya Seo, Yuji Nihei, Toshiyuki Shimano, Yuji Ohgi

SPORTS SCIENCE RESEARCH AND TECHNOLOGY SUPPORT, ICSPORTS 2015 （SPRINGER INTERNATIONAL PUBLISHING AG）  632   57 - 70 2016年

査読有り,  ISSN  1865-0929

　概要を見る

This paper describes a procedure for optimizing the design of the landing slope of the Zao jumping hill. The concept behind the design of the landing slope is that the landing slope should enable the spectators to witness an exciting spectacle, that the jumpers can land safely, and that it can be constructed with minimum cost. We regard these features as objective functions. The findings can be summarized as follows: it is possible to control the objective functions by changing the profile of the landing slope; there is not a unique optimal design solution, but the Pareto optimal solutions; a landing slope that gives safety on landing is almost equivalent to a landing slope that produces differences in the flight distance due to differences the jumpers' skill levels; there is a trade-off between the length of the flight distance and safety on landing; the construction cost is influenced by the horizontal distance between the edge of the take-off table and the K-point. The developed procedure would be applicable not only to Zao in Yamagata city, but also to all ski jumping hills in the world.

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An intelligent system for motor style assessment and training from inertial sensor data in intermediate level Ski jumping

Heike Brock, Yuji Ohgi

icSPORTS 2016 - Proceedings of the 4th International Congress on Sport Sciences Research and Technology Support （SciTePress）     101 - 108 2016年

　概要を見る

In this research we developed a wearable, augmented motion feedback system for ubiquitous training and motion assessment in mid-level ski jumping. Ski jump motion data captured with a set of inertial sensors were first transformed into meaningful kinematic motion information using an extensive processing system. Next, derived segment orientations, joint positions and joint angles were used to build and train motion knowledge on the base of the sport's common style and judging criteria. This intelligent machine knowledge was then applied to identify specific style information within incoming motion data that could be provided to the athlete as augmented motion feedback via a mobile training application. System validations on a set of test jumping data showed that style errors could be recognized and displayed well by the implemented system. We therefore believe the system to be suitable for the provision of kinematic motion feedback that could not be obtained without an extensive training support environment otherwise. Adding a real-time environment for athletesystem communication, this could lead to the creation of an ubiquitous training support application in future.

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Evaluation of a Community-Based Health Promotion Program with Online Off-Line Combination: The Effect of an Online Diet Record System on Self-rated Achievement

Shoko Miyagawa, Yuko Oguma, Yuji Ohgi

Procedia Computer Science （ELSEVIER SCIENCE BV）  100   768 - 775 2016年

査読有り,  ISSN  1877-0509

　概要を見る

The aim of this study is to clarify the effect of e-health community health promotion program, which consists of both online diet record system and off-line health activities. 49 participants are surveyed concerning self-rated sense of understanding and sense of control about calorie intake, nutrition balance, and physical activity along with basic information, internet usage and lifestyle habit are surveyed during 2009-2001. Self-rated sense of achievement regarding dietary understanding and dietary sense of control significantly increased in a group that utilized the online diet record system. Further analysis shows that the usage of the diet record system affects the self-rated sense of achievement while neither age, sex, answers of the preliminary questionnaire nor session participation had any effect.

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Intelligent Drift Reduction in Inertial Sensor Orientation Estimates Using Elementary Motion Knowledge

Heike Katrein Brock , Yuji OHGI

KEIO SFC JOURNAL 16 （ 1 ） 170 - 203 2016年

共著

Physical Activity, Fitness And Cognitive Function Among Community-dwelling Elderly - baseline Data Of Fujisawa Plusten Project.

武林 亨

MEDICINE AND SCIENCE IN SPORTS AND EXERCISE 47 （ 5 ） 216 - 216 2015年05月

ISSN  0195-9131

「スポーツ」の多様性を探る エビデンス・ベースド・スポーツの時代

仰木 裕嗣

Keio SFC J 14 （ 2 ） 24 - 41 2015年03月

エビデンス・ベースド・スポーツトレーニング/コーチング/ジャッジメント

仰木 裕嗣

電子情報通信学会大会講演論文集(CD−ROM) 2015 総合大会 2015年02月

Optimization of flight distance and robustness in discus

Kazuya Seo, Koji Shimoyama, Ken Ota, Yuji Ohgi, Yuji Kimura

Sports Engineering （Springer）  18 （ 1 ） 55 - 65 2015年01月

査読有り

センサ情報から身体動作を判別する (特集 動作を計測するためのセンサ技術とその応用)

仰木 裕嗣

バイオメカニクス研究 = Japanese journal of biomechanics in sports & exercise : 日本バイオメカニクス学会機関誌 19 （ 4 ） 249 - 255 2015年

身体活動コミュニティワイドキャンペーンを通じた認知症予防介入方法の開発 2‐2.来年度以降に向けた評価ツール・システムに関わる研究開発 身体活動量の評価

仰木 裕嗣小熊祐子, 齋藤義信, 佐藤智絵

身体活動コミュニティワイドキャンペーンを通じた認知症予防介入方法の開発 平成26年度 委託業務成果報告書    76 - 92 2015年

Dealing with Stiffness: Shaft Dynamics in the Golf Swing

Ken Ohta, Yuji Ohgi, Kazuhiro Shibuya

The Engineering of Sport 10 （ISEA）  72   298 - 303 2014年06月

研究論文（学術雑誌）, 共著,  ISSN  1877-7058

　概要を見る

A study was undertaken to investigate the influence of shaft stiffness on the deflection and the positioning of the club face during a golf swing. To accomplish this task, a theoretical model was developed that calculated deflections of golf shafts during the swing. Applying moment-curvature in relation to a shaft that had the bending stiffness, a differential equation and the boundary conditions that characterized its behaviour over the duration of the swing were generated. Incorporated into the bending moment-distribution are forces and torques acting at each end of the shaft. These loads were calculated using an inverse dynamics problem of the golf club during the swing. A motion capture system was utilized to collect the necessary data. Solutions to the equations of motion for the shaft were calculated numerically. The results have been presented as deflections along the shaft as functions of time. Bending deflections were determined in the plane of the club face and normal to this plane were calculated. (C) 2014 Elsevier Ltd.

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Sensor Data Mining on the Kinematical Characteristics of the Competitive Swimming

仰木 裕嗣

The Engineering of Sport 10 （ISEA）  72   829 - 834 2014年06月

研究論文（学術雑誌）, 共著,  ISSN  1877-7058

　概要を見る

The purpose of this study was to propose a new methodology for the automatic identification and the classification of the swimmers kinematical information during interval training of competitive swimming. Forty-five college swimmers attached the newly developed chest band sensor unit, which has a triple-axes accelerometer inside, and then performed a controlled interval training set with four stroke styles. The authors identified swimmer's states, such as the swimming/rest phases and the start, turn and goal touch events by using the trunk longitudinal acceleration (Ay). With the inductive inference based on the experimental results and the deductive inference based on the empirical rule on the interval training brought the estimation of the swimming time. For the classification of the swimming strokes, using the extracted swimming phase acceleration, the mean, variance and skewness of each bout were calculated. The authors compared different data mining algorithms for the stroke style classification with these descriptive statistics, such as mean, variance, skewness on the each axial acceleration as the independent variables and stroke styles as the depending variable. The accuracy of the stroke style classification by both the multi-layered neural network (NN) and the C4.5 decision tree were 91.1%. (C) 2014 Elsevier Ltd.

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Optimization of the Size and Launch Conditions of a Discus

Kazuya Seo, Koji Shimoyama, Ken Ohta, Yuji Ohgi, Yuji Kimura

The Engineering of Sport 10 （ISEA）  72   756 - 761 2014年06月

研究論文（学術雑誌）, 共著,  ISSN  1877-7058

　概要を見る

This paper describes optimization of the size and launch conditions of a discus. The objective function for optimization is the flight distance. Longer flight distance is better. Fourteen design variables are considered. Eight of the fourteen are concerned with the skill of the thrower. They determine the launch conditions, which are controlled by the thrower when he or she throws. The other six variables are concerned with the design of the equipment. These are the dimensions of the discus (width, thickness, radius of the metal rim and diameter of the flat center area on each side), the moment of inertia on the axis of symmetry and finally the mass of the discus. The dependences of size and the angle of attack on the aerodynamic data are estimated by using CFD (computational fluid dynamics) technique. Typical CFD results, including the effect of stalling, were confirmed by comparing the results with experimental data. As a result, the longest flight distance that could be achieved was 79 meters. In order to do this, the initial yaw rate on the axis of symmetry should be maximized. The mass should be the smallest. The moment of inertia on the axis of symmetry, the diameter of the flat center area and the width should be designed to be large. The air inflow to the discus should arrive from the upper side at the very beginning of the flight. (C) 2014 Elsevier Ltd.

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Concurrent Optimization of Both Skill and Equipment of a Discus

Kazuya Seo, Koji Shimoyama, Yuji Kimura, Ken Ota, Yuji Ohgi

Proceedings of the International Association of Computer Science in Sport Conference    88 - 93 2014年06月

査読有り

High-speed video image analysis of ski jumping flight posture

Masahide Murakami, Masato Iwase, Kazuya Seo, Yuji Ohgi, Reno Koyanagi

Sports Engineering April 2014 （Springer London）  17 （ 4 ） 298 - 303 2014年04月

研究論文（学術雑誌）, 共著,  ISSN  1460-2687

　概要を見る

Ski jumping flight posture was analyzed for achieving large flight distance on the basis of high-speed video images of the initial 40 m part of 120-m ski jumping flight. The time variations of the forward leaning angle and the ski angle of attack were measured from the video images, and the aerodynamic forces were calculated from the kinematic data derived from the images. Some correlations were investigated between the initial-speed corrected flight distance and such parameters as the angles of jumper, the initial transition time and the aerodynamic force coefficients. The result indicated that small body angle of attack was a key for large flight distance in the initial phase of flight because of small drag force, and that the most distinctive fault of beginners was too large body angle of attack and ski angle of attack leading to aerodynamic stall. Too small drag force does not give an optimal condition for large flight distance because the lift force is also too small. The ratio of the lift to the drag was larger than 0.95 for advanced jumpers.

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