著者

清水 哲雄 小松 治男 馬田 俊雄 高橋 清 佐藤 正矩

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:03875024)

巻号頁・発行日

vol.64, no.623, pp.2348-2353, 1998-07-25 (Released:2008-02-26)

参考文献数

3

被引用文献数

1

---

Understanding the spinning mechanism of an impacted golfball is an important factor in golf science and engineering. The rigid sphere model which considers the Coulomb-type slip friction presented independently by Daish and Kawamura (referred to here as the Daish-Kawamura model) seems to well explain the experimental results of golfball spinning. For a more general interpretation of the spin phenomenon, we attempted to modify this model by introducing a physical quantity called the "s parameter", which is defined as the ratio of the circumferential velocity of the ball to its centroid velocity. An experiment performed to verify the appropriateness of the new parameter introduction led to the following conclusions: The spin phenomenon in golf impact can be divided into two phases, in both of which the Daish-Kawamura model is effective. A method is described to evaluate the coefficient of slip friction under high sliding velocities, and the value is estimated as 0.07 for a slippery surface condition.

著者

伊坂 忠夫 Robert J. GREGOR 川村 貞夫

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:03875024)

巻号頁・発行日

vol.64, no.623, pp.2429-2436, 1998-07-25 (Released:2008-02-26)

参考文献数

20

被引用文献数

1 4

---

The purpose of this study is to derive the reasonable lifting movement from analysis of biomechanical characteristics of the snatch, back lift (BL) and leg lift (LL) in a skilled weightlifter. During the snatch lift, the differences between skilled and unskilled lifter appear in EMG and joint torque patterns. The skilled lifter utilizes the double knee bend technique and motor unit recruitment patterns in agonist and antagonist about joint might be reasonable to lift heavy weight. The present data suggest that skilled weightlifter has acquired the higher neuromuscular performance, which is required the control among the recruited muscles with regard to the tension and the timing of the coactivation and the contraction-relaxation. From comparison of BL and LL, it is suggested that BL has higher EMG activity and produces a much higher shear force about L 5/Sl joint which induces a low back injury. In case of LL, the shear force about L 5-Sl joint depends on the lifting posture. Moreover, it is revealed that the skilled weightlifter might have a lower shear force than unskilled person. From the experimental results, it is shown that the detailed instruction about lifting posture is needed to reduce the incidence of low back injury.

著者

石橋 彰 園田 計二 前之園 好爾

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:03875024)

巻号頁・発行日

vol.62, no.594, pp.721-728, 1996-02-25 (Released:2008-02-26)

参考文献数

8

被引用文献数

2 1

---

This paper derives new equations for calculating the efficiencies of differential gear drives using simple laws based on mechanics, When the new equations are used, the efficiency for speed reduction is lower than that for speed increase, in most cases. This is completely opposite to the case of the results obtained from the earlier equations. The reason for this is clearly shown by analyzing the power flows used for deriving the equations. It is found that the power flows used for deriving the earlier equations do not satisfy the boundary conditions due to an assumption which is unconsciously introduced in the process of deriving the equations. Numerical calculations are conducted and differences in the efficiencies are shown in the case of representative differential gear drives.

著者

水野 雅彦 酒井 英樹 大山 鋼造 磯村 吉高

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:03875024)

巻号頁・発行日

vol.71, no.711, pp.3208-3215, 2005-11-25 (Released:2011-03-04)

参考文献数

5

被引用文献数

2

---

The results of vehicle performance tests often vary depending on differences in the road surface temperature. It is believed that these changes can partially be attributed to the effect of tire surface temperature. The aim of this study is to develop a tire force model considering the dependence of tire surface temperature. The newly developed tire model is composed of two functions, the thermodynamic function that allows us to consider changes in the tire surface temperature and the force function that allows for the effects of tire surface temperature. The parameters of this model are identified using the measured data obtained with an indoor test facility. To prove the validity of the developed model, the surface temperature and the tire force values are predicted using this model. The simulation results agreed rather well with the experimental results.

著者

中川 智皓 竹原 昭一郎 須田 義大

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:03875024)

巻号頁・発行日

vol.75, no.749, pp.74-80, 2009-01-25 (Released:2017-06-09)

参考文献数

12

被引用文献数

4 2

---

In this research, the dynamic characteristics of a small wheel bicycle are investigated. The bicycle model is formulated by using multibody dynamics. Then, the stability of bicycles is analyzed by parametric study using the bicycle model. The effects of the parameters of tire diameter and head angle are examined by focusing on a small wheel bicycle. The straight-ahead stability and upstanding stability are evaluated at each parameter. The results show the tendency of stability at each parameter and the influential parameter to the small wheel bicycle is found. The driving experiment using the small wheel bicycle is performed. In the experiment, the stability of the small wheel bicycles with variable head angle is evaluated by the subjects. It is confirmed that varying head angle increases the stability of the small wheel bicycle. The results are corresponding with the simulation results and it is shown that the simulation captures the tendency of the stability and expresses the characteristics of the small wheel bicycle.

著者

原 敬 横川 隆一 甲斐 義弘

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:03875024)

巻号頁・発行日

vol.64, no.618, pp.604-609, 1998-02-25 (Released:2008-02-26)

参考文献数

12

被引用文献数

1 1

---

The purpose of this paper is to present a graphical method for evaluating task performance of a manipulator for a planar peg-in-hole assembly task. The manipulator has three revolute joints, including a compliant element, and performs the task in a plane. Further, an RCC (Remote Center Compliance) is mounted on the end-point of the manipulator. First, a force condition to avoid jamming on the chamfer is derived. A stiffness condition at the compliance center of the RCC is then obtained from the force condition. Under the stiffness condition, the manipulator can avoid the jamming on the chamfer. Second, a graphical method is proposed on the basis of the stiffness condition and a DMA (Dexterity Measure for Assembly) that was previously derived by the authors. Third, the method allows us to evaluate the task-performance of a manipulator (e.g. PUMA 560). Finally, the evaluation results show that the stiffness condition for avoidance of jamming on the chamfer is important in evaluating task-performance of a manipulator for a peg in-hole task.

著者

城越 教夫 日高 照晃

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:03875024)

巻号頁・発行日

vol.64, no.624, pp.3120-3127, 1998-08-25 (Released:2008-02-26)

参考文献数

5

被引用文献数

1 1

---

It is necessary to reduce gearing backlashes and bearing clearances at planet gears for the sake of minimizing the backlash of the planetary gear system for factory automation uses. However, the reducing backlash would further cause improper load distribution to each planet gear, and it would usually not be easy to keep smooth rotation of planetary gear system. To solve this problem this study experimentally investigated the influence of eccentricity of planet gears and the assembling condition on the load distribution of planet gears and the transmission error. It has revealed that there is each appropriate method to obtain better load distribution or smaller transmission error, respectively.

著者

城越 教夫 日高 照晃 賀勢 晋司

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:03875024)

巻号頁・発行日

vol.66, no.646, pp.1952-1958, 2000-06-25 (Released:2008-02-26)

参考文献数

5

被引用文献数

7 7

---

Reductions of meshing and bearing clearances are requisite in design and production of small backlash planetary gears. In this case, however, there is a risk of losing proper load distribution to each planet gears, which has risk of occurrence of non-working flank load. The state of non-working flank load increases unnecessarily working flank load and gives some undesirable influences on reliability of planetary gears. To solve this problem, this paper aims to analyze quantitatively about relations between the load distribution and position deviations of planet gears. These deviations are considered to be most influential to the problem in reality. About one type of the device with 4 planet gears, 20 kinds of combination pattern of the position deviations are selected out, and the influences of backlash, reduction ratio and gear module to the above relations are clarified. Consequently, allowable position deviations to avoid the state of non-working flank load are found out for various conditions and useful materials for design are obtained.

著者

堤 一郎

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:03875024)

巻号頁・発行日

vol.74, no.746, pp.2396-2402, 2008-10-25 (Released:2011-03-04)

参考文献数

30

---

The first domestically-built mine type electric locomotive is said to be the locomotive used at the Ashio Copper Mine in Tochigi Prefecture, Kanto District. Wheel arrangement of this electric locomotive was 0-4-0, and built in 1893 by Ashio Copper Mine Works. Mechanical and electric engineer relation to this locomotive building was Mr. Kumazo Miyahara who graduated at Telegram Vocational Training School of Ministry of Communications. In addition to this locomotive, other two examples of mine type electric locomotive building are introduced. In the final section of this paper, significance of domestic building of mine type electric locomotive examples are discussed from the perspective of history of technology and mechanical engineering heritage.

著者

末岡 淳男 劉 孝宏 白水 健次 江村 篤裕 中野 寛

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:03875024)

巻号頁・発行日

vol.70, no.689, pp.38-45, 2004-01-25 (Released:2011-03-04)

参考文献数

5

被引用文献数

4 3

---

This paper deals with the occurrence mechanism of the squeal and chatter phenomena generated in a bicycle disk brake and their countermeasures. From the results by bench test apparatus, it was made clear that the squeal is in-plane vibration in the direction of rotor surface with frequency 1kHz caused by the frictional characteristics with negative slope with respect to the relative velocity generated in the vibration system including brake components and spokes, and the chatter is another frictional vibration with frequency 500Hz in which the squeal occurring in the in-plane direction of rotor and the out-of-plane vibration of rotor due to Coulomb friction are superimposed through the internal resonance relation caused by temperature increase of rotor during braking. The measures for squeal and chatter were taken on spokes and hub, and the validity was confirmed by using bench test apparatus.

著者

屋代 春樹 高田 一

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:03875024)

巻号頁・発行日

vol.72, no.714, pp.435-440, 2006-02-25 (Released:2011-03-04)

参考文献数

6

被引用文献数

1

---

It is important to reduce the vibrations of an Interior Permanent Magnetic motor that is generally installed in electrical vehicles, fuel cell vehicles, and hybrid electrical vehicles. The purpose of the study here is to build up the torque ripple reduction methodology by controlling the working currents on IPM motor. The distributed winding IPM motor with 48 teeth on the stator and 4 pairs of poles on the rotor is treated. The relating equation between torque and three phase alternating currents is shown firstly, utilizing the torque that results from the Finite Element Analysis of the plane electromagnetic field. Secondly, high order currents are derived from the equation and superposed on the basic currents in order to reduce the torque ripple. Finally, the plane electromagnetic field analysis is performed again with the currents including the high order ones and a torque ripple reduction of more than 25 dB with a torque drop of 2.2% is obtained.

著者

岡村 茂樹 藤田 聡 荒水 照夫 池永 雅良 早川 邦夫 舟木 秀尊

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:03875024)

巻号頁・発行日

vol.68, no.675, pp.3137-3142, 2002-11-25 (Released:2008-02-26)

参考文献数

2

---

Most of non-rubber type isolation systems apply frictional force. One of the famous non-rubber type isolation systems is Friction Pendulum Bearing (: FPB) system. When using friction pendulum system in the open air circumstances, some have pointed out that long term durability of the systems must have been taken into account and it might have been very difficult to maintain the coefficient of friction. In this study, dynamic motion of the isolated structure model with 4 of FPB systems are investigated, especially in in-plane mode, considering a variance of friction coefficient of one system, a distribution of the mass of superstructures. The result and the analysis of the shake table test using 3-storey steal-frame model is presented in this report.

著者

岡本 和也 山口 健吾 丸 典明

出版者

The Japan Society of Mechanical Engineers

雑誌

日本機械学会論文集 C編 (ISSN:03875024)

巻号頁・発行日

vol.72, no.718, pp.1840-1847, 2006

被引用文献数

3

---

We propose a method for following motion control of the mobile robot by using Linear Visual Servoing (LVS). Following motion control is realized by the following motion of the body to the target object keeping a desired distance. Following motion control by using LVS is based on linear approximation of the transformation between binocular visual space and motion space of the mobile robot. Motion space is defined by translational velocity and rotational velocity of the robot coordinate system which is attached at the center of gravity of the mobile robot. Some experimental results are presented to demonstrate the effectiveness of the proposed method.

著者

章 忠 井 和章 三宅 哲夫 今村 孝 堀畑 聡

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:03875024)

巻号頁・発行日

vol.74, no.739, pp.642-649, 2008-03-25 (Released:2011-03-04)

参考文献数

10

被引用文献数

1 1

---

The direction of a generated sound source can be estimated by humans using the time difference between both ears and the characteristics of the sound. However, it is very difficult to create an estimation system using a computer and two microphones. Aims of this study are the achievement of three dimension sound localization with two microphones. We have developed the sound source direction estimation system, in which the sound source direction can be shown by two angles, the horizontal angle α and the vertical angle, β. The former is presumed from the difference of the arrival time when the sound progresses from the source to right and left ear, and the latter is presumed from spectrum correlation analysis using head related transfer function (HRTF). In this study, we propose a novel sound source direction estimation method, in which the feature difference of two recorded microphone signals is used. As a result, an average correct estimation rate of 96% was obtained in determining the location of 11 kinds of object sounds.

著者

金井 謙二 渡辺 崇

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:03875024)

巻号頁・発行日

vol.76, no.771, pp.3172-3174, 2010

参考文献数

7

---

For the human motion detection by camera, it is usually needed to use sensors and/or markers. We propose a method that does not handle any sensors nor markers, instead, that adopts optical flows. By applying this method, we can analyze synchronization between human motions and classify moving direction of crowds. The optical flows are estimated by the Lucas-Kanade method. The result of the optical flows is assigned to a hue circle, and the histogram of the hue gives information to identify human motions. Utilizing this color information makes our method robust to the environmental changes. We defined the combined Bhattacharyya coefficient and use it to detect the synchronization of the human motions. In this paper, two persons dance choreography and the results before and after the practices are quantitatively evaluated. The crowds' classification is performed depending on the moving directions of the crowds. We also describe the method to detect unusual acts. These functions are available to score the group performances in games and to detect the persons doing normal and abnormal actions.

著者

広瀬 茂男 長久保 晶彦 外山 良成

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:03875024)

巻号頁・発行日

vol.57, no.540, pp.2679-2686, 1991-08-25 (Released:2008-02-21)

参考文献数

12

被引用文献数

3 30

---

The configurational design for a wall-climbing robot which is capable of moving on diversified surfaces of wall and has high payload capability, is discussed, and a developed quadruped wall-climbing robot, NINJA-1, is introduced. NINJA-1 is composed of 1) legs based on a 3D parallel link mechanism capable of producing a powerful driving force for moving on the surface of a wall, 2) a CP (Conduit-wire-driven Parallelogram) mechanism to adjust the posture of the ankles, and 3) a VM (Valve-regulated Multiple) sucker which can provide suction even if there are grooves and small differences in level of the wall. Finally, the data of the trial-manufactured NINJA-1, and the up-to-date status of the walking motion are shown.

著者

涌井 伸二

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:03875024)

巻号頁・発行日

vol.65, no.636, pp.3252-3259, 1999-08-25 (Released:2008-02-26)

参考文献数

5

被引用文献数

1 1

---

The precise positioning stage is ordinary mounted on the isolated table. For the positioning of its stage, PID compensator is widely used. There are many PID tuning methods, such as the ultimate sensitivity method. However, these methods are effectively applied to the plants described by "first-order lag+dead time". Then, it is difficult to realize the desirable positioning for the stage mounted on the isolated table by the simple applying of these method. Therefore, the knowledge based adhoc parameter tuning has been carried in the production field. However, this tuning easily introduces the tradeoff between the command and disturbance responses and then an adequate compromise is required. In this circumstances, we have doubts whether absolute positioning ability inherent in the stage itself is actively used. In this paper, in order to progress the positioning performance of the stage, we try to derive the tuning formulas based on Kitamori's method. The command and disturbance designated formulas are derived. Through the numerical simulation, it is clear that the practical formulation can be derived.

著者

尾形 哲也 菅野 重樹

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:03875024)

巻号頁・発行日

vol.65, no.633, pp.1900-1906, 1999-05-25 (Released:2008-02-26)

参考文献数

16

被引用文献数

1

---

This study discusses the communication between autonomous robots and humans through the development of a robot which has an emotion model. The model refers to the internal secretion system of humans and it has four kinds of the hormone parameters to use to adjust various internal conditions such as motor output, cooling' fan output and sensor gain. We surveyed 126 visitors at '97 International Robot Exhibition held in Tokyo (Oct. 1997) in order to exaluate psychological impressions of the robot. As the result, the human friendliness of the robot was confirmed and some factors concerning with the human robot emotional communication were discovered.

著者

呉 志強 畔上 秀幸

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:03875024)

巻号頁・発行日

vol.61, no.583, pp.930-937, 1995-03-25 (Released:2008-02-26)

参考文献数

29

被引用文献数

6 10

---

We present a practical method of numerical analysis for optimization problems of domains in which natural vibration problems of linear elastic bodies are defined. In this paper, we apply the traction method that was proposed as a solution to the domain optimization problems to elliptic boundary value problems. The treated problems are those which determine the domain that maximizes a specified vibration eigen value, which is defined by the squared natural frequency, and that moves several specified vibration eigen values in a specified direction. Using the Lagrange multiplier method, we obtain the shape gradient functions for these domain optimization problems from the optimality criteria. We show the successful resolution of the problems of beamlike plates clamped at one end and at both ends.

著者

白仁田 和彦 林 健一郎 大坪 昭文

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:03875024)

巻号頁・発行日

vol.70, no.689, pp.192-199, 2004-01-25 (Released:2011-03-04)

参考文献数

10

---

This paper describes a method of giving impression words for images based on colors. 160 impression words are prepared, and colors which are strongly related to each of the 160 impression words are registered into the system in advance. In this system, we adopt Lab color space which is a color coordinate system and can obtain exact color difference between pixels and extract main colors of images based on the results of clustering in Lab color space. The number of main colors of an image is determined when the sum of pixels of the main colors is larger than 85% of all the pixels in the image, and the colors with the larger number of pixels are determined in ascending order. We propose a distance between the main colors and the registered colors. In this system mCn combinations of distances between m colors registered in an impression words and n main colors are obtained. Using the mCn distances, we calculate a minimum distance and an average distance every 160 impression words. By the comparison of the minimum distance and the average distance of each impression word, the system determines suitable impression words for the image. Experimental results show the proposed method to be effective.