著者

久保 登 森 みどり

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.779, pp.2940-2952, 2011 (Released:2011-07-25)

参考文献数

22

---

Drive video recorders (DRs) have been installed on a plenty number of the taxicabs in large cities in Japan. This paper discusses how to carry out a detailed traffic accidents analysis using drive video recorder data obtained in Tokyo. The sequential motions of the cars concerned before and after the crash are illustrated throughout a process in the case studies of two traffic accidents. The causes of the accidents are discussed as well as measures to prevent the accidents and the DR data requirements for effective analysis based on the motion picture and the log data recorded by the commercial DRs. This newly-developed approach makes those possible to carry out the reproduction of the accident process, the estimation of the causes and the background factors, and the consideration of the preventive safety measures. It is more effective to make such analysis by using not only the DR data but also the Internet resources such as a map, an aerial photograph and other information. The requirements of DR hardware and DR data for the proper analysis of the accidents were also examined.

著者

川副 嘉彦 武田 幸弘 中川 慎理

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.726-737, 2013 (Released:2013-03-25)

参考文献数

14

---

Several former top players sent a letter to the International Tennis Federation (ITF) encouraging the governing body to revisit the question of rackets. In the letter, the players wrote that racket technology has led to major changes in how the game is played at the top level. This paper investigated the physical properties of a new type of racket with active piezoelectric fibers appeared recently in the market, and predicted the various factors associated with the frontal impact, such as impact force, contact time, deformation of ball and strings, and also estimated the racket performance such as the coefficient of restitution, the rebound power coefficient, the post-impact ball velocity and the sweet areas relevant to the power in tennis. It is based on the experimental identification of the dynamics of the ball-racket-arm system and the approximate nonlinear impact analysis with a simple swing model. The predicted results with forehand stroke model can explain the difference in mechanism of performance between the new type racket with active piezoelectric fibers and the conventional passive representative rackets. It showed that this new type racket provides higher coefficient of restitution on the whole area of string face and also gives larger rebound power coefficients particularly at the topside and bigger powers on the whole area of string face but the difference was not so large. It seems that the racket-related improvements in play are relatively small and the players themselves continue to improve, accordingly there is a gap between a perception and reality.

著者

宮本 大資 梶原 逸朗 細矢 直基 西留 千晶

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.1760-1771, 2011 (Released:2011-05-25)

参考文献数

11

被引用文献数

2 2

---

This paper proposes a vibration testing and health monitoring system based on an impulse response excited by a laser ablation. High power YAG pulse laser is used in this system for producing an ideal impulse force on structural surface. It is possible to measure high frequency vibration responses in this system. A health monitoring system is constructed by this vibration testing system and a damage detecting algorithm. A microscopic damage of structures can be extracted by detecting fluctuations of high frequency vibration response with the present health monitoring system. In this study, loosening of bolt tightening torques is defined as the damage of the system. The damage is detected and identified by statistical evaluations of measured frequency response data with Recognition-Taguchi method.

著者

大和 秀彰 古田 貴之 富山 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.77, no.776, pp.1441-1453, 2011 (Released:2011-04-25)

参考文献数

27

---

This paper presents a new methodology of attitude estimation for cost-effective and small-size inertial measurement units, consisting of tri-axial gyroscope sensors, accelerometers and geo-magnetometers. Introduced for the algorithm development is a quaternion feedback structure, where bias terms in the gyroscope rate information, appearing in the phase-locked loop, are identified with the theoretical guarantee of the global and asymptotical stability. The bias-term identification and modification process is performed continuously without the influence of the disturbance by applying the proposed disturbance detection scheme and a conventional vector matching method. Practical validity of the presented framework is fully evaluated by experiments. The evaluation result shows that the approach in this paper can offer superior drift-free performance with property of disturbance rejection under arbitrary high-frequency test motion of spatial rotation and translation.

著者

浅井 勝彦

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.803, pp.2532-2545, 2013 (Released:2013-07-25)

参考文献数

10

被引用文献数

1

---

In this research, I investigated the design of non-circular pulley for a force/torque profile adjustment mechanism. I proposed the generalized analytical design method of the non-circular pulley applicable to the majority of structures. By using this design method, the torque acting on the non-circular pulley and the force acting on the flexible part twisted around the non-circular pulley can be converted mutually to obtain a desired torque/force profile. Also I demonstrated the design of the non-circular pulley for a spring balancer and for an arm weight compensation mechanism. Furthermore, I investigated the design limit of the non-circular pulley, and showed that too long effective radius, too long offset length, and too short radius of curvature cause the problem of impractical non-circular pulley shape. From the analysis of the occurrence condition of each case, it became clear that the derivative of the effective radius is important for avoiding too long offset length and that the effective radius and the second derivative of that are important for avoiding too short radius of curvature.

著者

丸野 裕太郎 Aydin Tarik ZENGIN 岡島 寛 松永 信智 中村 憲仁

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.808, pp.4721-4733, 2013 (Released:2013-12-25)

参考文献数

18

被引用文献数

2 6

---

Electric-powered personal vehicles have been used as a convenient transportation device. A front-drive-type personal vehicle STAVi, that is easy for elderly but also disabled persons, to climb on from a bed has been focused on. However, front-drive-type personal vehicles are difficult to operate because their over-steering characteristic is strong owing to free casters. If the vehicle can be driven by an easy joy-stick operation, it will be a comfortable function for all users. In previous studies, we proposed a simple modeling error compensator which achieves a desired driving characteristics using a simple reference model, and the effectiveness was evaluated by simulations. In this paper, we propose a control system for STAVi using a modeling error compensator with a non-linear reference model to realize a comfortable under-steering characteristics. At first, the advantage of proposed controller is summarized. The STAVi's over-steering characteristic is modified to be under-steering one by proposed controller. As an experimental result, the additional assistance is necessary for a beginner. The phase-lead compensator for beginners is designed to adjust the maneuverability depending on the skill level. The maneuverability is evaluated by driving experiments on the slope.

著者

小島 広久 向井 拓幸

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.68, no.668, pp.1113-1118, 2002

---

Attitude synchronization is a key technology to facilitate the capturing process of tumbling satellites. Tumbling motion of the satellites is a nonlinear system and the inertia ratio of the satellite is a dominant parameter of the motion. Estimation of the inertia ratio of the tumbling satellites is thus important function for a chaser satellite to synchronize its attitude motion with the tumbling satellite motion. The present study is devoted to investigate an adaptive sliding mode control (ASMC) algorithm applied to attitude tracking maneuvers. The adaptive law added to the sliding mode control (SMC) algorithm is employed to estimate the inertia ratio of the tumbling satellite. Attitude tracking performances of the ASMC method is studied numerically to compare with those of a quaternion feedback control method and a simple SMC method. It is shown that the precise synchronization can be executed by the ASMC method even if there exist some errors between the real value of the inertia ratio of the tumbling satellite and the estimated one at the beginning of tracking maneuvers.

著者

沢 俊行 唐沢 明浩 原田 容一 清水 章弘

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.52, no.476, pp.1455-1461, 1986

---

The design method of bolted joints with gaskets is almost based on experience, and the sealing performance is not made clear by theoretical analyses. In the present paper, discussion is made on the distribution of contact stress in the bolted joints fastened with tap bolts, when a clamped part with a gasket is the cover of a pressure vessel and a circular flange. The distribution of contact stress is analyzed as a three-body contact problem, using the three dimensional theory of elasticity. Moreover, the contact stress is measured by means of ultrasonic-waves. In addition, the force ratio (the ratio of an increment of the bolt axial force to an external load) and the maximum stress caused in bolts taking account of a bending moment are analyzed. For verification, experiments are carried out, and the analytical results are in fairly good agreement with the experimental ones.

著者

逢坂 一正 藤本 真作 小野 敏郎

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.58, no.552, pp.2489-2494, 1992

---

Optimal reference trajectories for n-link robot manipulators are planned. They are generated from the performance indices which are the integral of the square of acceleration, jerk, and so on of the trajectory with respect to the control time. The optimal reference trajectories are compared through an experiment in high-speed motion control of a 2-link robot manipulator, and a good control performance is obtained in the case of higher continuity of the trajectory.

著者

野原 英孝

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.2331-2339, 2012 (Released:2012-06-25)

参考文献数

4

---

Currently, plasma gouging machines supplied by domestic equipment manufacturers are classified according to orifice gases used in them; some use mixtures of 30% hydrogen and argon, whereas some use only nitrogen. Stainless steel and aluminum alloy, which were previously used in arc welding, are used with a carbon steel for plasma gouging, thus resulting in high efficiency and high quality gouging. The plasma gouging process using only nitrogen allows carbon steel to be processed with a single gas, which is a potential selling point. However, plasma gouging or cutting using a mixture of gases is more expensive owing to the consumption of the two orifice gases. In order to use hydrogen, which is a combustible gas, special safety control is necessary in the storage of hydrogen gas cylinders. Compressed air can be easily used as an orifice gas; therefore, the author investigated various properties of the plasma gouging method using compressed air.

著者

伊東 弘一 赤木 新介 太田 雅晴

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.48, no.431, pp.998-1004, 1982

---

地域暖房の熱輸送システムの設計計画問題において, (イ)配線系サイズの縮小化, (ロ)ポンプ規模の縮小化および(ハ)熱交換器系サイズの縮小化という設計目標をそれぞれ独立した目的関数として考え, 一つの非線形多目的最適化問題として定式化した. 上記問題に対し, 計算機を対話形式で援用してシステム構成機器の主要設計要目を合理的に決定する一手法を提案し, 設計事例を通じてその有効性の検証と最適解の特徴を検討した.

著者

八尾 佳宏 貝原 俊也 藤井 信忠 堀 栄一

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:18848354)

巻号頁・発行日

vol.77, no.784, pp.4718-4729, 2011 (Released:2011-12-25)

参考文献数

9

被引用文献数

1 2

---

In this study, scheduling method using a combination of auction-type real-time scheduling and simulation is proposed in order to automate the scheduling in dynamically changing manufacturing environment. The control mechanism which is essential for executing real-time scheduling and simulation simultaneously is developed and implemented. The auction algorithm for the real-time scheduling which improves the delay of delivery date and amount of setup time at the same time is proposed. Also the method of simulation during the real-time scheduling which can predict the changing situation of the shop and automatically take countermeasures by adjusting the scheduling precondition is proposed and its effectiveness is confirmed by computational experiments. With these methods, prototype system is developed and tested under the condition of actual machining line. As a result, it is clarified that the proposed system has the ability to respond flexibly to dynamically changing manufacturing situation.

著者

佐藤 博則 山下 進介 宇津野 秀夫 松久 寛 山田 啓介 澤田 勝利

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.775, pp.989-1003, 2011 (Released:2011-03-25)

参考文献数

7

被引用文献数

2 2

---

Life style related diseases such as hypertension and diabetes promote arteriosclerosis which causes circulatory diseases. It is important to evaluate arterial condition for prevention of circulatory diseases. The pulse wave velocity method has become familiar as a vascular test because it is easy and non-invasively. However, the accuracy of the method seems not to be high because it just compares two points ignoring the frequency dependence and reflection waves from peripheral vessels. In this study theory of pulse wave propagation considering such effects was formulated. A new method to identify the reflection ratio from peripheral vessels and pulse wave velocity was proposed. This method was verified by experiment using a silicon tube and applied to measure the pulse wave propagation of human arm as a case study. The results showed that this method has possibility to apply to measure the pulse wave propagation of human pulse wave.

著者

宮近 幸逸 Daing Mohamad Nafiz Bin Daing Idris 小出 隆夫 Imaduddin Helmi Bin Wan Nordin 安藤 和彰

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.775, pp.597-603, 2011 (Released:2011-03-25)

参考文献数

14

被引用文献数

1 2

---

This paper presents a study on effects of rim and web thicknesses on root stresses of thin-rimmed helical gears. Root stresses of thin-rimmed helical gears with symmetric web arrangement of various rim and web thicknesses, which were meshed with the solid helical gear, were measured from the beginning of engagement to the end of the engagement by the strain gauge method. The changes of the root stress from the beginning of engagement to the end of engagement were examined for the thin-rimmed helical gear with symmetric web arrangement. The meshing position (worst loading position), where the maximum root stress occurred, was determined for the thin-rimmed helical gear with symmetric web arrangement. The effects of rim and web thicknesses on the root stress, the maximum root stress and the position of the maximum root stress were clarified.

著者

原 豊 酒向 俊明 水原 晋 新美 智秀

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.619, pp.972-978, 1998

---

Optical novelty filter based on the two-wave mixing in a photorefractive BaTiO<SUB>3</SUB> crystal is applied to motion detection for the purpose of its application to the robot vision. A simple method is proposed to realize the reflex vision system that a human being possesses. Our method uses a photo detector array to detect the output from the optical novelty filter and the detector element that obtains the highest signal is selected. By simulations using a simple animations, it is showed that the larger or the faster object can be detected in higher probability. Tracking a moving object is demonstrated with a 2&times;2 photo-transistor array and the selective circuit including the exclusive gate circuit.

著者

山口 智実 樋口 誠宏 矢野 章成 藤田 和正

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.674, pp.3115-3121, 2002

被引用文献数

1

---

This paper presents a new and effective assembly model by using a fixture with passive RCC function. Previously, in a peg-in-hole task, such functions for skillful assembly as RCC, contact force sensing and so on have been supplied to a "peg-device" like a hand-manipulator, not a "hole-device" like a fixture. Therefore the characteristics of a fixture with passive RCC function in this task is investigated in this paper. The peg-in-hole task model by using the "RCC fixture" is constructed on vertical (x-z) plane. And the performance of this task is investigated by the quasi-static analysis, which was proposed by Whitney, to evaluate the characteristics of it. From the results of the analysis, it has been made clear that the RCC fixture has shown the insertion behavior unlike conventional RCC applied to a peg near the entrance of hole.

著者

二瓶 美里 小竹 元基 鎌田 実

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.784, pp.4591-4604, 2011 (Released:2011-12-25)

参考文献数

27

被引用文献数

2 2

---

The automobile has an important impact on the daily lives of elderly people and their ability to participate in society. However, the deterioration of physical skills caused by aging is also a cause of vehicular accidents. In this paper, we conduct research into the cognitive function on driving ability, and propose a method to evaluate the driving ability of elderly drivers. The proposed system that the system is a computer simulator rather than an actual on-road driving experiment evaluates the ability to follow a road, the ability to avoid obstacles, and the ability to escape from unexpected dangers. To identify the operating characteristics and define an assessment index, 102 people over the age of 65 were surveyed on their driving attitudes. The investigation showed that the tasks and assessment index, and based on this system, another 92 elderly people participated in evaluation tests. The results showed there was a significant difference between elderly and younger drivers in terms of road-following and obstacle-avoidance ability. In addition, an assessment index with a five-level rating system, based on the characteristics of elderly drivers, was proposed.

著者

佐藤 準一

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.64, no.627, pp.4109-4114, 1998

著者

岡田 昌史 渡辺 将旭 長谷川 将臣

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.804, pp.2854-2863, 2013 (Released:2013-08-25)

参考文献数

15

---

For dynamic control of a robot, a torque/force control will be necessary because the robot model is represented by a dynamic equation. A torque/force control requires a torque/force sensor or a current sensor(for DC servo motor) for feedback loop, however, they occupy large volume and weight or have low precision and time delay. Therefore, the robot system sometimes has a local position control in the motor drivers from the safety point of view. In this paper, we propose a design method of position-based dynamic control using an autonomous control method based on an orbit attractor, which is realized by a simple deformation of the conventional algorithm. In addition, for the orbit attractor control, it is necessary that an orbit of the state variable is not crossing in the state space. When the orbit is very close, vector field of the orbit attractor along the orbit can not be defined correctly. A dimensional expansion of dynamics is also proposed to design a controller. These methods are evaluated by experiments using a two-dimensional biped robot.

著者

藤原 浩幸 得田 修 渡邉 啓二 大野 友則

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.4153-4163, 2013 (Released:2013-11-25)

参考文献数

6

被引用文献数

1 1

---

Armored fighting vehicles with Mine Resistant Ambush Protection (MRAP) designed to counter Improvised Explosive Devices (IEDs) have attracted special interest recently. This paper describes dynamic response of a shock absorption structure to blast load. Mathematical models have been developed to predict the effects of blast load on seat-passenger systems. A blast test using scale models was performed to evaluate the blast forces acting on the vehicle and the human body. By comparing the results of mathematical models with the results of the blast test, a simple vehicle acceleration model was derived. As a result, mathematical models were improved and come to attain higher accuracy.