著者
仇 時雨 神谷 好承 青柳 誠司 岡部 佐規一 牧野 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:03875024)
巻号頁・発行日
vol.57, no.542, pp.3240-3246, 1991-10-25 (Released:2008-02-21)
参考文献数
9

When a robot is used for doing work such as laser processing or water-jet processing, not only the trajectory of the end-effector but also its velocity is very important from the viewpoint of the processing accuracy. On the other hand, several curve-interpolation methods have been suggested, but it is cannot be said with certainty that the correct velocity control of the trajectory is possible. In this study, in order to solve this problem, a method using the clothoidal curve is introduced, and this method enables the velocity control with high accuracy for any trajectory.
著者
野田 伸一 石橋 文徳 井手 勝記
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.59, no.562, pp.1650-1656, 1993-06-25 (Released:2008-02-26)
参考文献数
9
被引用文献数
9 7

The induction motor is used in many industries. These days motor noise reduction is often required due to environmental concerns. This paper is concerned with the reduction of motor noise. The relationship of exciting force and vibration mode of the stator core is analyzed. An exciting force as an electromagnetic radial force was applied to the stator core. Analysis was performed for the case of a continuous distributed force and the case of a discrete multipoint exciting force. The vibration behavior of the core was analyzed theoretically, numerically (FEM) and experimentally with respect to modes, frequency and phase of exciting force. It has been confirmed that : 1. in the continuous distributed excitation, the core vibrates when M=±N and the exciting frequency coincides with the natural frequency, 2. in the discreted multipoint excitation, the core vibrates when M±N=mK. Here, N is the natural frequency mode, "is the excitation frequency mode, m is an integer, and K is the number of applied points of the exciting force.
著者
土屋 和雄 渡辺 誠治 山田 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:03875024)
巻号頁・発行日
vol.58, no.549, pp.1366-1370, 1992-05-25 (Released:2008-02-26)
参考文献数
6
被引用文献数
1 2

This paper deals with a mathematical model of the mechanics of rigid bodies connected by rotary joints. The method is based on the Lagrangian formulation. The kinetic energy is written in terms of the angular velocities. The expression for the kinetic energy has a homogeneous quadratic form in the angular velocity, the coefficient matrix of which is given by the products of triangular matrices. The equations of motion are derived from the Lagrange's equations for the quasi-coordinates, the angular velocities of the bodies. The equations of motion become recursive forms due to the structure of the expression of the kinetic energy of the system. The algorithm of the inverse dynamics, which follows from the equations of motion, becomes also a recursive form like the algorithm based on the Newton-Euler equations of motion. Since the algorithm is based on the Lagrangian formulation, it can be extended to more complex systems that include flexible bodies, the constraints of which limit the motion of the systems, and so on.
著者
鈴木 曠二
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.50, no.457, pp.1736-1739, 1984

The Dynamic Soaring is the soaring technique making use of the wind gradient. The order, Albatross belongs to, includes several species which use this technique and have various scale. Main conclusion is as follows: They practice almost physically similar dynamic soaring. The larger one practices a larger dynamic soaring and requires a stronger wind than the smaller one does, in the wind near the sea surface. Such a scale effect corresponds with the fact that a Wandering Albatross lives in the zone of the westerlies of the Southern hemisphere; on the other hand, a Streaked Shearwater which is smaller than it lives in areas where it is not so windy. But if the wind profile was almost linear, the said relation between the scale of a bird and the wind strength would be reversed.
著者
小林 秀明 相馬 仁 谷藤 克也
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:03875024)
巻号頁・発行日
vol.74, no.748, pp.2932-2938, 2008-12-25 (Released:2011-03-04)
参考文献数
9

This paper deals with the effects of axle misalignment of a truck with independently rotating wheels (IRWs) on the wheel lateral force and the flange wear. Since the truck with IRWs lacks for self-steering ability, it is concerned that the wheel continues flange contact with rail due to the effects of axle misalignment in parallelity and the flange wears rapidly under the continuous flange contact condition. Numerical simulations are carried out, using an analytical vehicle model with the axle misalignment. Obtained results are as follows : Even if misalignment is a little, the vehicle with IRWs which dose not have self steering ability tends to run under the flange contact condition, and then continuous lateral force acts between the flange and the rail. The vehicle with IRWs, which has axle misalignment only in the lateral setting, does not have tendency of continuous flange contact. In the range of misalignment in parallelity considered in this paper, the wheel lateral force increases with the increase of the misalignment, and the wheel lateral force of IRW increases more than that of the solid wheelset. The wheel lateral forces generated due to the misalignment are equivalent to the ones generated in the curved tracks, the radii of which make the attack angles corresponding to the misalignment.
著者
山本 圭治郎 兵頭 和人 石井 峰雄 松尾 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.67, no.657, pp.1499-1506, 2001-05-25 (Released:2008-02-26)
参考文献数
18
被引用文献数
17 22

In order to realize a power assisting suit for assisting a nurse caring a patient is her arm, a hardness sensor of muscle using load cell and a pneumatic rotary actuator utilizing pressure cuffs have been developed. The power assisting suit consists of shoulders, arms waist and legs made of aluminum, and is fitted on the nurse body. The power assisting suit was originated with the concept of a master and slave system in one body. The arms, waist and legs have the pneumatic rotary actuators. The pneumatic rotary actuators construct with pressure cuffs sandwiched between thin plates. The action of the arms, waist and legs of the nurse were sensed with the muscle hardness sensor utilizing load cell with diaphragm mounted a sensing tip. The dent of the sensing tip corresponds to the hardness of the muscle so that exerting muscle force produces electric signal. This paper gives the design and characteristics of the power assisting suit using the cuff type pneumatic rotary actuators and the muscle hardness sensor verifying its practicability.
著者
永瀬 和彦 橋 弘矩
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.74, no.744, pp.1938-1947, 2008-08-25 (Released:2011-03-04)
参考文献数
26
被引用文献数
1 1

The friction coefficient μ on the contact point position between a wheel flange and a rail is said to seriously affect on the occurrence of the wheel-climb derailment. However, the method to quantitatively and exactly evaluate the μ has not suggested until to the present. The authors proposed a method to easily and exactly evaluate the value, and made it clear by an experiment, employing a 1/5 scale model track and model truck. The result obtained through the experiment indicates that the value on dry rails has a similarity with that of the adhesion coefficient, and that the dry rail on the main line keeps the value at high level. Using the μ value obtained by the studies, the risk of the wheel-climb derailment was evaluated. As the result of the evaluation, they found that higher μ value than the conventionally used one should be introduced for the risk evaluation of the derailment, and that very short term lateral force below 60 ms should be observed on the steep curvatures.
著者
小野 京右 武川 浩士
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.63, no.608, pp.1110-1117, 1997 (Released:2014-03-12)
参考文献数
5

A mathematical method of complex modal analysis and an experimental identification procedure of modal parameters for nonproportionally damped mechanical systems have been established thus far. However, the physical structure of complex modes of nonproportionally damped systems has not been thoroughly understood. This paper deals with a physical and graphical interpretation of complex modes in comparison with real modes of proportionally damped systems using the complex plane and the complex vector space. It is explained why the resonance vibration of nonproportional-ly damped systems does not exhibit the natural mode shape which appears in the free vibration of the same system. The condition that makes the resonance vibration mode approximately coincide with the natural mode shape of the free vibration is discussed.
著者
西原 修 坂谷 祐輔 北野 弘明 平岡 敏洋 熊本 博光
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.738, pp.250-258, 2008-02-25 (Released:2011-08-16)
参考文献数
8

The Meihan highway linking Kameyama in Mie Prefecture and Tenri in Nara Prefecture is one of most accident-prone areas in Japan. Representative accident factors that have been identified for the Meihan highway are chronic speeding and complex road alignments, including many sharp curves and steep slopes. One particular section is known as the “Omega curve” as the road shape is similar to the Greek character “Ω”. In this study, the probable effects of proposed plans to improve the road alignment of the Nakahata section are investigated by performing driving simulations to identify typical hazards, ranging from traffic conflicts to vehicle accidents. It was found that incidents that begin as a minor traffic conflicts can frequently escalate to become a fatal accidents. It was also found that improved road alignment generally reduces the required tire forces. For typical traffic conflict patterns reproduced using the driving simulator, it was found that road alignment resulted in considerable improvements in safety indexes which are effective indicators for the occurrence of rear-end collisions.
著者
山田 健介 宮本 共生 臼井 清一
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.71, no.708, pp.2557-2562, 2005-08-25 (Released:2011-03-04)
参考文献数
8
被引用文献数
4 4

The paper presents a design and characteristics of a new holonomic omnidirectional moving vehicle, which simultaneous and independently controlled translational and rotational motions. The moving vehicle has four rubber balls instead of wheels. Each ball is driven by two rotating rollers. But the system has only four actuators. The kinematics of the moving vehicle is analyzed and the control algorithms are derived for the holonomic and omnidirectional moving vehicle. The experimental results show that the proposed new type of moving mechanism has good characteristics and the sensor on board is useful for autonomous moving under relatively large disturbance.
著者
山中 仁寛 中易 秀敏 三好 哲也 前田 多章
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.719, pp.2248-2256, 2006-07-25 (Released:2011-03-04)
参考文献数
17
被引用文献数
3

A new method is proposed to measure the useful field of view (UFOV) when one can recognize the objects by visual task. Since the distance from fixation point to target mark is the strength of stimuli, the psychometric curve is utilized for UFOV by the statistical estimation by Probit and Staircase methods. An approximation by ellipse is also applied to represent the contour of the UFOV. The proposed method enables one to estimate the threshold of recognition with probability that means the UFOV with the detection probability. Therefore, it is proposed in this paper to determine the threshold in any direction from fixation point of the UFOV with visual task by psychometric curve. The availabilities of the proposed method are examined for accuracy and efficiency by the experiments.
著者
星川 秀利 藤本 浩志
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.69, no.680, pp.1080-1085, 2003-04-25 (Released:2008-02-26)
参考文献数
12

The purpose of this study is to investigate the influence of lower saddle height on the knee joint. Five healthy male pedal at 60 rpm against the work load of 100 and 200 W. Three saddle heights of 80, 90 and 100% of trochanteric leg height are selected in this study. During each trial, the position data of the right lower limb's joints by the video camera and the force data of the right pedal by the force sensor are measured. Using these data, the inverse dynamics analysis is done, and the following results are obtained. The peak link force acting on the knee joint and the peak knee extension moment do not indicate any change over the three saddle heights, however, the angles at their peak values shift to the knee flexion as the lower saddle height. These results indicate that the lower saddle would overload at the knee joint.
著者
藤本 浩志 加藤 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.61, no.582, pp.641-646, 1995-02-25 (Released:2008-02-26)
参考文献数
8
被引用文献数
1 1

This paper deals with the method of controlling an A/K prosthesis which allows disabled persons to ascend a staircase. Since conventional A/K prostheses are capable of only the function of walking on a level surface, disabled persons wearing conventional A/K prostheses have been compelled to walk on stairs with unnatural posture. The research study of developing powered A/K prostheses has the important themes of not only developing the mechanism of the prosthesis but also devising the controlling method. By measuring the axial forces acting on the socket ; which is the man-machine-interface, during walking, using the six axis force-moment sensor, the torque of a disabled side hip joint was calculated. We devised the control method using this torque as the control signal. Results of clinical walking experiments showed that a subject wearing the A/K prosthesis was able to walk with a joint angle pattern similar to that of unaffected persons. Furthermore, from the results of the inverse dynamics analysis, the subject was found to generate a similar torque pattern and power pattern at his disabled side hip joint. Thus the effectiveness of the controlling method proposed in this study was confirmed.
著者
小出 祐一 中川 正紀 福士 直己 石垣 博邦
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.73, no.725, pp.66-71, 2007-01-25 (Released:2011-03-04)
参考文献数
9
被引用文献数
1 1

In vibration design, we need to estimate the damping ratio to calculate the dynamic response of a structure. In particular, an estimation of its probability distribution is important to carry out so-called probabilistic design. For this paper, we developed an estimation method using the Bayesian approach to generate the probability distribution of the damping ratio from a vibration test with a small sample size. The Bayesian approach has special significance to engineering design, where available test data is invariably limited, for the approach can systematically incorporate subjective judgments based on experience or indirect information with observed data. We supposed that the probability distribution of the damping ratio has a normal distribution. Therefore, we applied the Bayesian approach to estimate unknown parameters of the distribution. In addition, we compared this method with a method of moments classified as a classical estimation and investigated the influence of sample size by conducting an evaluation test. With the results of our analysis, we came to the following conclusions. First, he true standard deviation of the damping ratio is less than 0.4, and the prior distribution of the standard deviation ranges between 0 and 0.5. (1) The estimated probability distributions determined by the Bayesian approach and the classical approach almost fully agree across more than 40 specimens. (2) The Bayesian approach provides good agreement, less than 10 percent error, with a true standard deviation for approximately 10 specimens. Even though the prior distribution of standard deviation ranges between 0 and 1.0, almost the same accuracy is obtained for approximately 10 specimens.
著者
藤井 洋 丸井 悦男 江馬 諭
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.51, no.462, pp.p436-445, 1985-02

びびり振動中のドリルの挙動を,振動特性の異なるドリルを用いて書斎に調べた.励振エネルギは,切れ刃が傾くことによって穴底面に創成される起伏の位相が,直前の切削によるそれよりおくれることにより供給されることがわかった.振動数は刃先を支持したドリルの固有振動数にほぼ等しい,切れ刃の傾きを考慮して振動発生限界を求めた結果,被削材一回転中の振動数が奇数となるときに不安定領域が存在することが見い出された.
著者
斉藤 俊 千葉 洋三
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:03875024)
巻号頁・発行日
vol.64, no.623, pp.2389-2394, 1998-07-25 (Released:2008-02-26)
参考文献数
10

Two kinds of road racer bicycles are employed to research vibration characteristics of driving bicycles. After obtaing the natural frequencies and modes by vibration test in the non-driving state, practical driving tests are carried out. The acceleration of vibration in the middle of the handles and under the saddles are measured and the corresponding spectral density functions are calculated based on FFT method. The results show that in the driving bicycles, the dominant frequencies exist between 10 Hz and 50 Hz and the lower two modes in the non-driving state are excited.
著者
中村 友道 廣田 和生 友松 健一 高井 睦夫 岩瀬 敏彦 宇和川 誠一 班目 春樹 岩壺 卓三 齋藤 孝基
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.668, pp.1064-1072, 2002-04-25 (Released:2008-02-26)
参考文献数
7
被引用文献数
1 1

A partial but full-size mock-up test of practical steam-generator U-bend tubes in nuclear power plants has been carried out, where the test model has been set in a HFCF-123 fluid two-phase flow loop. U-bend tubes are supported with so-called "Anti-vibration Bars (AVB) ", which have two types of AVBs in Japan, 7-span type and 5-span one. Both types of AVBs have been examined and it is found that tubes with AVB supports shows no large amplitude vibration up to 150% flow rate to the practical condition. Basic data for the fluidelastic instability are obtained when some tubes have been set to be flexible at some contact points with AVBs.
著者
村上 和男
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.73, no.733, pp.2456-2463, 2007-09-25 (Released:2011-03-04)
参考文献数
12

It is specially analyzed about the problem of the pitch of stationary sound in the acoustic analytic subjects of brass instruments. It is modeled as a combination of the conical horn elements for the trumpet. First, the end of mouthpiece is set as the closed end, the resonance frequency is calculated as a characteristic value of the modeled trumpet by the technique of Cavity Resonance. Next, when it is played, the effective input impedance at the end of mouthpiece and those relative angles are calculated. Based on these characteristics, quantitative examined considerations are added to the playing methods, and a blowing pattern is set up. Furthermore, it is calculated the virtual additional length for the end of mouthpiece. It is examined correspondence with the playing methods of brass players. This playing method is taken into consideration, the CAD system for the pitch design of trumpet is built, and a suitable example to the pitch design is shown, with the utility of the system. The validity of a blowing pattern is shown.
著者
磯田 隆司 陳 鵬 光武 伸一郎 豊田 利夫
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.65, no.636, pp.3282-3289, 1999-08-25 (Released:2008-02-26)
参考文献数
8
被引用文献数
2 2

This paper presents an Omni Directional Mobile Robot which can run on off road and run over an obstacle. The robot is constructed with four crawler-roller-motor-units and called "roller crawler-type of omni-directional mobile robot". Each crawler-reller-motor-unit can be driven independently and the motion of the robot can be controlled by the speed of motors. We also designed a position and velocity control system for the robot. The robot can be automatically controlled to run in optional direction and to track an orbit. The efficiency of the mechanism and the control method has been verified by many practical running tests and computer simulations.
著者
遠藤 央 廣瀬 健治 平田 泰久 小菅 一弘 菅原 雄介 鈴木 公基 篠塚 博之 新井 浩幸 阿久根 圭 神林 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:03875024)
巻号頁・発行日
vol.75, no.755, pp.2028-2035, 2009-07-25 (Released:2017-06-09)
参考文献数
23
被引用文献数
3 3

We propose a novel car transportation system termed as iCART (i__-ntelligent c__-ooperative a__-utonomous r__-obot t__-ransporters). This system transports cars using two robots that move in coordination. This car transportation system can transport cars of any size and offers various functions such as parking, valet parking, towing service, and the transportation of cars inside a factory, onto a ferry, and in complicated parking areas. The robots in this car transportation system comprise three modules: the mobile base module, the lifter module, and the connecting module. This paper describes the details of the operation mechanism and the basic algorithm of each module. A leader-follower-type distributed motion control algorithm is applied to the proposed system and is used in an experiment performed to verify the validity of its function.