著者

嶋脇 聡 酒井 直隆

出版者

一般社団法人 日本機械学会

雑誌

日本機械学会論文集C編 (ISSN:18848354)

巻号頁・発行日

vol.78, no.787, pp.883-891, 2012 (Released:2012-03-25)

参考文献数

27

---

Finger deformities refer to the symptoms where a flexed or extended joint becomes fixed in one direction and is prevented from returning to a normal state due to muscle or tendon abnormalities around the joint as a result of trauma or a pathological abnormality. The deformities exist in numerous forms, and their causes are known to be either a muscle imbalance or tendon rupture. We focused on the finger deformity forms of the boutonnière and swan-neck deformity. To clarify the formation mechanisms of these deformities, conventional studies have used cadaveric fingers whereas in this study we used the finite element method to model the mechanism of human finger flexion and extension (extensor tendons, flexor tendons, phalanges, tendon pulleys, and ligaments). Using this model, flexion angles of the distal interphalangeal (DIP) and the proximal interphalangeal (PIP) joint were calculated with conditions for a tendon (central band, lateral band, flexor digitorum superficialis tendon) rupture and tendon tension abnormalities. The results have shown that the conditions which most resembled the boutonnière deformity were those of the central band removal model, and the conditions which most resembled the swan-neck deformity were those of the flexor digitorum superficialis tendon removal model and the tendon tension abnormalities. These results are in agreement with those from clinical observations and cadaveric finger experiments, and demonstrated that the finite element method was effective for clarifying the mechanisms for finger deformity formations.

著者

佐野 嘉則 堀 貴之 早川 拓人 藪田 哲郎

出版者

一般社団法人 日本機械学会

雑誌

日本機械学会論文集C編 (ISSN:18848354)

巻号頁・発行日

vol.78, no.790, pp.2171-2186, 2012 (Released:2012-06-25)

参考文献数

11

---

It is one of great functions required for a robot to perform a task instead of a human. Particularly, if a human skilled task is realized to a robot, and moreover it might be applied widely, it is possible for a robot to accept many demands. Here, we adopt the yoyo manipulation as a skilled task with the limber motion of the human upper limbs, which is intended to realize with a 9DOF redundant finger-arm robot system. Unlike conventional method using the yoyo dynamic model, human skills in the yoyo manipulation are extracted by measuring the yoyo operation of a human being with a motion capture system, and are implemented to the robot system. In this way, the yoyo operation can be performed by the robot whose results are friendly understood as human being knowledge. Furthermore, this study tries without a vision sensor, as it were, in the blindfold. Here, we show that continued control of the yoyo can be obtained using both force sensor and position control in its difficulty condition.

著者

近藤 亜希子 土岐 仁 廣瀬 圭

出版者

一般社団法人 日本機械学会

雑誌

日本機械学会論文集C編 (ISSN:18848354)

巻号頁・発行日

vol.79, no.803, pp.2351-2361, 2013 (Released:2013-07-25)

参考文献数

13

被引用文献数

1 2

---

This paper proposes the measurement method of 3D posture using inertial sensors. The proposed method estimates the 3D posture (Roll-Pitch-Yaw angles in local coordinate) using the 3-axis angular velocity and the 3-axis acceleration. The 3D posture is compensated for the drift error of gyro sensor output by the translational and gravity accelerations of accelerometer output. The nonlinear state equation and the nonlinear measurement equation were established to estimate 3D posture. The Extended Kalman filter and the Unscented Kalman filter are applied to these equations. The measurement experiment was conducted to clarify the accuracy of proposed method using the experimental setup installing the rotary encoders. The results of the Unscented Kalman filter indicated higher than those by the Extended Kalman filter. In addition, the proposed method estimated the 3D posture compensating the drift error of gyro sensor in the measurement experiment generating the translational acceleration. Therefore, the proposed method can be used for the measurement of body motion.

著者

藤井 文夫 井上 吉弘 新田 高洋

出版者

一般社団法人 日本機械学会

雑誌

日本機械学会論文集C編 (ISSN:18848354)

巻号頁・発行日

vol.78, no.788, pp.1133-1142, 2012 (Released:2012-04-25)

参考文献数

11

被引用文献数

3 6

---

Domino is a popular entertainment to enjoy the pleasing wave propagation in a row of solid pieces. This play game may be, however, a tough research subject of dynamic contact mechanics, because finite rotation, contact and friction are included in toy mechanics and these nonlinear effects are all of scientific interest. The major concern of this paper is to develop a computational model to study the domino wave propagation in a long straight row. More specifically, a total of N dominoes are modeled to rectangular rigid-body solids in shape of D (width) x H (height) x B (breadth). Equally spaced dominoes in a long straight row (L=492cm) are assumed to simply rotate around the front bottom edge. To trigger the wave propagation, the first domino is slowly inclined till its side diagonal slightly goes beyond the plumb line. The successive collision mechanism between individual toppling dominoes is investigated as a 2D problem in contact mechanics and we obtain an excellent agreement between the model prediction and experimental result.

著者

下田 昌利 近藤 晃 劉 陽

出版者

一般社団法人 日本機械学会

雑誌

日本機械学会論文集C編 (ISSN:18848354)

巻号頁・発行日

vol.79, no.807, pp.4014-4027, 2013 (Released:2013-11-25)

参考文献数

21

被引用文献数

2

---

This paper presents an optimum design method considering structural performances and Kansei, which has been becoming an important issue for product designs with maturation of consumer demands. The response surface methodology combined with the design of experiment technique is applied to a bicycle frame design problem. The strength and the rigidity calculated by FEM are used as the evaluation functions for the structural performances. Three dimensional rendering models are constructed with computer graphics software, and used for the Kansei evaluation. The Kansei performances such as “individual” and “elegant” are evaluated by the Semantic Differentials technique and quantified. A road-bicycle frame is focused on as an application example of this method. Sizes of the cross section at both ends, position and angle of rotation at the midpoint of each frame are defined as the design variables to be optimized. By using the response surfaces between the design variables and the performances, the form of road-bicycle frame is optimized under various objectives and constraints. The form with the optimized design variables is visualized with the CG software.

著者

田中 伸司 吉冨 雄二

出版者

一般社団法人 日本機械学会

雑誌

日本機械学会論文集C編 (ISSN:18848354)

巻号頁・発行日

vol.78, no.794, pp.3615-3629, 2012 (Released:2012-10-25)

参考文献数

23

被引用文献数

1

---

This study aims definition of complex phenomena arising under screw thread fastening process and deep understanding of past relevant knowledge. So far, authors have been studied on screw fastening mechanism of a clamped body with M10 bolt-nut by using 3D elastoplastic FE analysis. In this paper, more precise analytical model is developed and the bolt-nut fastening process is calculated. Consequently, following matters were revealed. (a) Greatly complicated deformation of bolt-nut joined threads area under contacting was clarified qualitatively. Supporting contribution percentages of each thread to axial load was calculated; especially the first thread of joining screw thread supported about 31% of axial force. (b) Spring constant of bolt-nut or clamped part calculated by the present FEM was well accorded with some theoretical equations within 7% error. Contribution of elongation of each region with the bolt also agreed with these equations. Most of all, the validity of Sawa-Maruyama's equation was showed. (c) During fastening process, development of stress or strain at the bolted joint was visualized compatibly alongside of past knowledge and information.

著者

永瀬 和彦 別所 雅章 生田 憲人 漆原 健

出版者

一般社団法人 日本機械学会

雑誌

日本機械学会論文集C編 (ISSN:18848354)

巻号頁・発行日

vol.79, no.806, pp.3432-3441, 2013 (Released:2013-10-25)

参考文献数

3

被引用文献数

2 2

---

To keep on-time performance of commuter trains in mega cities, the skillful brake handling is required for the drivers on the approach of the stations. However, on the course of the training for the newly comer drivers, such skill has been telepathically given by their instructors, and none of theories nor quantitative instructions has been introduced. The authors proposed a method to quantitatively evaluate the brake handling skill on the approach of the stations. Using the newly proposed method, they investigated the data piled up in the event recorder of the EMUs operated the JR West Ohsaka Kanjoh Line, one of the most densely train-operated commuter lines in the JRs. On the investigations, they confirmed that the brake handling skill could be easily and quantitatively evaluated by the method. Then, they applied it to investigate the trains operated on the Tohkaido Main Line between Kyoto, Osaka and Kobe, where the interval of the stations is longer and the scheduled operating speed is higher than the formally investigated line. The results of the study are briefly reported in the paper.

著者

吉田 準史 川越 伸幸 河村 智博

出版者

一般社団法人 日本機械学会

雑誌

日本機械学会論文集C編 (ISSN:18848354)

巻号頁・発行日

vol.78, no.792, pp.2837-2847, 2012 (Released:2012-08-25)

参考文献数

12

被引用文献数

2

---

Bicycle is a popular vehicle for general public because of the low price and the easy maintenance, and will be more importance vehicle by the low environmental loading in the future. Improvement of bicycle ride comfort is one of important factors to increase the popularity. In this study, subjective evaluation test and reduction of bicycle vibration were performed to improve it. In the subjective evaluation, low frequency seat vibration was found to affect the ride comfort very much. Subsequently, transfer path analysis (TPA) and hammering test were performed to obtain vibration characteristic of the bicycle for reduction of the seat vibration. Through TPA, rear frame of the bicycle was found to have high influence to seat vibration than that of front side and the vibration behavior was obtained by modal analysis. For reduction of the seat vibration, a spring was inserted to the front of the seat and steel plates were attached to rear frame to increase the stiffness. As a result, the acceleration level at running condition was decreased about 10 dB by the modification, and the ride comfort was improved so much.

著者

小松崎 俊彦 岩田 佳雄

出版者

一般社団法人 日本機械学会

雑誌

日本機械学会論文集C編 (ISSN:18848354)

巻号頁・発行日

vol.78, no.786, pp.420-430, 2012 (Released:2012-02-25)

参考文献数

10

---

In this study, a virtual sound production system is developed where the difference frequency component appears as the secondary audible sound at a point of interference locally by the nonlinear interaction of two independently radiated ultrasounds while they travel directionally and intersect each other. The design of high-directive ultrasonic radiator, followed by the investigation of virtual sound production performance has been done theoretically as well as experimentally. It is known from these investigations that the fairly local sound reproduction in free space is possible, yet the sound pressure level of the secondary field is small. The results have also shown that the generated virtual sound area is dependent on both the difference frequency and the intersection angle of two carrier waves emitted by two sound sources.

著者

伊達 央 大川 真弥 滝田 好宏 菊地 惇

出版者

一般社団法人 日本機械学会

雑誌

日本機械学会論文集C編 (ISSN:18848354)

巻号頁・発行日

vol.79, no.806, pp.3389-3398, 2013 (Released:2013-10-25)

参考文献数

11

被引用文献数

2 11

---

This paper presents the technique for improving the accuracy and reliability of an autonomous mobile robot localization. Localization based on 2D LIDAR is not always satisfactory due to occlusion. Use of 3D LIDAR improves the reliability by greater field of view. However, lack of 3D objects around the robot may result in poor matching between the observation and the 3D map. Even in this case, the different brightness of the ground surface helps localization. In this paper, we propose an efficient expression of 3D map by considering of LIDAR intensity. Experiment result shows successful localization in a trail through outdoor open grass fields.

著者

大島 裕子 足立 渡 辻内 伸好 小泉 孝之

出版者

一般社団法人 日本機械学会

雑誌

日本機械学会論文集C編 (ISSN:18848354)

巻号頁・発行日

vol.78, no.796, pp.3947-3958, 2012 (Released:2012-12-25)

参考文献数

17

---

In this paper, local polynominal regression is proposed as a metamodel for the optimal design. Local polynominal regression is often used for smoothing. Smoothing and approximation are applied for the different purpose, however these two methods are based on the similar theory. Therefore local polynominal regression is forecasted to be able to approximate functions. So the theory of local polynominal regression is extended to multivariate predictors for optimal design, and its effectiveness for approximation is verified. Next, more suitable optimization method that uses characteristics of local polynominal regression is suggested. Additionally, the comparison of local polynominal regression and other metamodels shows its features. As a result of the consideration, next four points are clarified. (1)LOESS that uses local quadratic regression and tricube weight function is most suitable for the approximation. (2)The metamodels based on local polynominal regression are able to use for the structural optimization and its characteristics are available for the optimization based on the gradient. (3)The accuracy of local polynominal regression is better than Kriging and RBF interpolation when the sample size is small. However, the property is reversed when the sample size is large. (4)The accuracy of local polynominal regression is better than Kriging and RBF interpolation when the response has noises. The fact shows local polynominal regression is suitable for the metamodel of montecarlo simulations and experiments.

著者

樋口 盛一 山信田 連三

出版者

一般社団法人日本機械学会

雑誌

日本機械学会論文集C編 (ISSN:00290270)

巻号頁・発行日

vol.15, no.51, pp.2-5, 1950

被引用文献数

1

---

材料の複雜な機械的性質が住々にして, その材料の他の簡單な物理的, 機械的性質によつて説明されることがある.こうした立場からシャルピー衝撃値に注目し, このものが近似的に, ブリネル硬さと伸び率とによつて表わし得ることを提言した.しかして本文の主要な部分はシャルピー衝撃値, ブリネル硬さおよび伸び率に関する諸家の各種の実験データを引用し, それらがおゝむね上の提案を支持していることを述べたものである.

著者

石山 新太郎 山口 克彦

出版者

一般社団法人 日本機械学会

雑誌

日本機械学会論文集C編 (ISSN:18848354)

巻号頁・発行日

vol.79, no.799, pp.718-725, 2013 (Released:2013-03-25)

参考文献数

6

被引用文献数

1 1

---

Prototype remotely-operated vehicle equipped with high resolution TV monitor and underwater radiation measuring instrument was developed and actual condition of contaminated soil in the regulation pond in Fukushima was investigated. Remarkable contaminated point was observed beneath rainwater outfall of impounding reservoir(Length×Width×Depth; 112m×30m×3.5m) in the order of 3.3~5.24μSv/h. It is found that contaminated small particles in the order of 1-3mm are deposited in the polluted mud at the bottom of the reservoir and suspended by disturbance of water flow, and the contaminated zones in the order of 0.75-3.5μSv/h are distributed in a patchy fashion caused by confluent of outfall in the demarcated region(10m×10m×10m).

著者

藤本 由紀夫 新宅 英司 田中 義和 藤吉 潤

出版者

一般社団法人 日本機械学会

雑誌

日本機械学会論文集C編 (ISSN:18848354)

巻号頁・発行日

vol.78, no.791, pp.2438-2449, 2012 (Released:2012-07-25)

参考文献数

8

被引用文献数

4 5

---

Pad type compressive force sensor suitable for high speed impact force measurement is developed. A piezoelectric film is sandwiched by a pair of the thin metal sheets. The electric wire is connected to the metal sheets which are the electrode of piezoelectric film. The whole of the sensor is covered by thin resin sheet, and layer components inside the sensor are fixed together in one body. A sensor is about 1mm in thickness and it can be made in the various shape according to the purpose of use. Several pad sensors are made for trial purpose, and the performance are examined through experiments by applying fluctuating loads and impact loads. Finally, the pad sensor is applied to the impact force measurement of golf ball shot by setting up the sensor to No5 and No9 golf irons.

著者

芝田 京子 井上 喜雄 岩田 祥孝 片川 準也 藤井 涼

出版者

一般社団法人 日本機械学会

雑誌

日本機械学会論文集C編 (ISSN:18848354)

巻号頁・発行日

vol.78, no.791, pp.2483-2495, 2012 (Released:2012-07-25)

参考文献数

33

被引用文献数

4 9

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Lumbago occurs when load causes malformation of the flexible intervertebral disks of the lumbar vertebrae. The conventional method of measuring load on the intervertebral disk is an invasive method in which the internal pressure of the intervertebral disk is measured by directly inserting an electrode. In this study, intervertebral disk load is derived indirectly by the noninvasive estimation method that uses three-dimensional motion analysis system and signal processing to estimate the shape of the lumbar vertebrae. Specific estimation method is shown as follows. First, vertebra is assumed to a rigid body. Next, lumbar vertebrae are approximated with an arc using 3-D positional coordinates. Finally, average of the intervertebral gap is estimated. Accordingly, because the proposed method only entails applying markers to the surface of the back and taking pictures with cameras, it is safe and does not require surgical procedures. Furthermore, this method allows estimation of intervertebral disk load in a moving subject. In this paper, the proposed method is described in detail. And an experiment in which intervertebral disk load is estimated from stationary postures is executed. Moreover the proposed method is compared with the conventional method. As a results, the experiment shows that the proposed method is effective in that the magnitude correlation tendencies of intervertebral disk load estimated with the proposed method are qualitatively consistent with the tendencies calculated from actual measurements of internal pressure.

著者

田原 誠 鈴木 智 野波 健蔵

出版者

一般社団法人 日本機械学会

雑誌

日本機械学会論文集C編 (ISSN:18848354)

巻号頁・発行日

vol.77, no.781, pp.3386-3397, 2011 (Released:2011-09-25)

参考文献数

19

被引用文献数

1

---

The attitude sensor mounted on unmanned systems is required high accuracy attitude under the dynamic acceleration environment for the autonomous attitude control. In order to estimate attitude by using a quaternion based on extended Kalman filter (EKF) , the attitude sensor detects a direction of the gravity by using a tri-axis accelerometer. However, accelerometers are usually sensitive to both the gravity and dynamic accelerations. In this paper, the dynamic accelerations are dealt with explicitly, and two types of algorithms are proposed. In the first approach, measured accelerations are filtered, and divided into the gravity and dynamic accelerations. Using only the gravity, EKF estimates high accuracy of attitude. This algorithm can be realized with relatively small amount of computation, and have a good effect under the short dynamic acceleration environment. The second approach demonstrates adequate performance with EKF which includes the dynamical model of accelerations. This paper shows a critical comparison of attitude estimation algorithms under the dynamic acceleration environment for the autonomous control of unmanned systems.

著者

福住 敦 竹原 昭一郎 長谷 和徳 吉村 卓也

出版者

一般社団法人 日本機械学会

雑誌

日本機械学会論文集C編 (ISSN:18848354)

巻号頁・発行日

vol.77, no.777, pp.1686-1695, 2011 (Released:2011-05-25)

参考文献数

16

被引用文献数

1 3

---

In this study, the vertical jump is examined as a basic study of jump. And we examine the influence of each muscle of the human body in vertical jump. The human body is modeled as four rigid bodies and analyzed in detail by using the model that includes muscles of the leg. In this research, the mechanism of jump is discussed by using numerical model to which the concept of multibody dynamics and biomechanics is adapted. We performed the experiment of jump and observe the feature behavior of vertical jump. Experimental results show that the angle of each body becomes vertical for ground and the change of the foot angle is small. Then we perform the numerical simulation referring to this experimental data. In order to reduce the amount of calculation, we calculate muscular activity level by correlating it with fewer parameters. We discuss which muscles are necessary for vertical jump. It is found that vasti exerts the biggest power and gluteus maximus has the highest state of normalized muscle activity.

著者

鈴木 幸仁 井筒 正義 釜道 紀浩 石川 潤 古田 勝久

出版者

一般社団法人 日本機械学会

雑誌

日本機械学会論文集C編 (ISSN:18848354)

巻号頁・発行日

vol.77, no.776, pp.1413-1428, 2011 (Released:2011-04-25)

参考文献数

10

被引用文献数

2

---

There are many researches to identify operator's dynamic characteristics in manipulating human-machine interaction systems. Analyses of operator's dynamic characteristics provide a clue to develop human-friendly systems that assists skill development. However, these researches mainly discuss single hand operations, and there seems to be little researches for two hand (bimanual) operations. To develop useful operational systems, the analyses of operator's dynamic characteristics in bimanual operation are indispensable. This research aims to clarify proficiency of operator's skill in bimanual operation. Concretely, the proficiency is evaluated by using an experimental human-machine interface for bimanual operations that provides three different mechanical impedances. The characteristics of operators are evaluated by tracking performance to references generated randomly and skills to draw geometric patterns in a two dimensional plane. In the experiment, the extent of proficiency was also compared with each other for the three different mechanical impedance models. It has been confirmed that the proposed evaluation method can successfully clarify the extent of proficiency of operators' skills. It was also observed that there was little difference in the extent of proficiency among the three mechanical impedances.

著者

平田 大貴 山田 泰之 大室 健 森田 寿郎

出版者

一般社団法人 日本機械学会

雑誌

日本機械学会論文集C編 (ISSN:18848354)

巻号頁・発行日

vol.78, no.786, pp.547-556, 2012 (Released:2012-02-25)

参考文献数

11

---

This paper proposes a new jumping unit that using chemical energy. Conventional jumping robots have difficulties to equip both lightweight and high output energy at the same time. In regard to this, chemical energy of black powder was adopted. Using explosives allows jumping robots to get high energy instantaneously. First of all, acceleration and velocity characteristics of the cylinder were clarified by experimental cylinder. The approximate expression of pressure change in the cylinder was derived based on the characteristics. Second, expressions of jumping theory were lead and relationships between some parameters (mass, rod-area, cylinder stroke) and jumping height were simulated. Curves with a peak were given from all of those parameters and existence of optimal value was clarified. The significance of the simulation was shown by jumping motion of about 2000mm by the experiment. Finally, four-legged robot dummy with jumping unit that change direction, control of height and isolated ignition were available, is developed. Trajectory of jumping motion was examined when the direction of cylinder was changed from vertical condition. Effectiveness of proposed method was confirmed from jumping height of 720mm with cylinder angle of 10 degree.

著者

佐藤 峻介 髙橋 正樹

出版者

一般社団法人 日本機械学会

雑誌

日本機械学会論文集C編 (ISSN:18848354)

巻号頁・発行日

vol.79, no.801, pp.1526-1539, 2013 (Released:2013-05-25)

参考文献数

14

被引用文献数

3 5

---

Recent years, it has been required accurate and agile attitude control of satellites. For this purpose, the necessity of Control Moment Gyros (CMGs) has been increasing, which can generate much higher torque than Reaction Wheel which is used for a conventional spacecraft actuator. CMGs have singularity problem that they cannot output a desired torque. Several singularity avoidance methods have been proposed, but they can fail to output the desired torque through the mission because of their singularity avoidance action. In this paper, we focus on singularity and CMGs' angular momentum and propose a singularity avoidance method by planning path in angular momentum space. Because output torque from CMGs depends on path of angular momentum, we plan the angular momentum path that avoids singularity and its length is short as possible by application of A* algorithm. It is shown from the simulations that the proposed method can realize desired output torque and assured singularity avoidance.