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

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

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

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

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.

著者

森 みどり 中易 秀敏 三好 哲也

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.79, no.803, pp.2408-2423, 2013 (Released:2013-07-25)

参考文献数

21

被引用文献数

1 1

---

In order to keep a highly safe and reliable system of car driving, it is important that the system would be considered as a man-machine system including not only the feature of vehicle movement but also human perception, cognition, and motion of a driver. In this paper, it is examined to clarify the relation between feature of eye movements and driving behavior in conventional and unconventional situation by the experiments using the driving simulator and the eye tracking system. The measurements of time histories of eye movements were performed in the situation of different traffic regulation by the simulator. It is recognized in both turns that typical patterns of eye movements in horizontal axis appeared between the start and end of the turns. It is found from the time histories of eye movements by synchronizing that of vehicle data that the appearances of fixations were distributed uniformly on the trajectories of vehicle by trained drivers from the start of turning to the end, while the appearance of fixation by untrained drivers are concentrated in the beginning of turning or the end. These facts mean that the untrained driver did not receive visual information during the operation of turning, therefore the trajectories of vehicle by untrained driver showed the overshooting in the right turn and undershooting in the left turn.

著者

倉迫 涼一 大日方 五郎 鳥谷 和史

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.800, pp.991-1002, 2013 (Released:2013-04-25)

参考文献数

13

被引用文献数

1 1

---

Lightening each part is needed as one method to improve the Fuel Economy of the car. On the other hand, a certain amount of mass is required for the brake rotor as thermal capacity because the main role of the brake is to convert the kinematic energy of the vehicle into the frictional thermal energy for decelerating the vehicle. Therefore, the appropriate heat design becomes important aiming at lightening brake parts. Many thermal analyses to design the strength and the cooling performance concerning the brake rotor are done. However, there are a few papers that treat the relation between the thermal analysis and the brake friction force. Authors have been developed the simple calculation method of the temperature on the friction surface where the pad and rotor come in contact. Then, it is found that contact form is one of factors in fluctuating brake friction force from the bench test data and the calculated friction surface temperature. In this paper, the calculation method of two dimensional temperature distribution of the rotor is proposed. The calculated results are effective to confirm the detail of radial temperature distribution of the rotor as a short time under braking. The tested pads and rotors were analyzed by EPMA on the friction surface. These results show that a detectable amount of tin is difference. It is found that the fluctuating brake friction force has affected by the relationship between the friction surface temperature and the melting point of tin.

著者

倉迫 涼一

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.78, no.786, pp.462-473, 2012 (Released:2012-02-25)

参考文献数

6

被引用文献数

2 1

---

Demands to vehicles performance from environmental view points are growing these days. Lightening each part is needed as one method to improve the Fuel Economy of the car. The main role of brakes is to transfer the kinematic energy of the vehicle to the dissipative thermal energy, and accordingly to lead the deceleration of the vehicle. On the other hand, a steady braking performance is important because it drives comfortably. The appropriate design of brakes for the stable performance requires the understanding of the temperature distribution based on the analysis of heat transfer. The friction force in a brake system is generated by making contact of the pad with the rotor. This study presumed that the friction force is depending upon the temperature of the surface where the pad and rotor come in contact. This study proposed a calculation method for estimating the temperature of the friction surface. Moreover, this study conducted the experiments to compare with the estimates from the proposed method. The experimental results agree with the estimations calculated from the proposed method. Based on the temperature distribution calculated by this method, considering how the shapes of the pad have an influence on the generated brake force.

著者

川島 進 渡邉 豊

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.778, pp.2376-2388, 2011 (Released:2011-06-25)

参考文献数

24

---

The center of gravity of a moving train differs time to time due to variety of number of passengers on board. There can be significant difference of 3D-locations of the center of gravity on the same train between at rush hour time and at off peak one. It is essential to detect the location for preventing rollover accidents of trains on which the critical speed of rollover for them depends. In this respect, this paper applies the innovative new theory of detecting 3D-locations of the center of gravity of a moving object for trains, which was invented by the second author of this paper and abbreviated as D3DCG(1). D3DCG was created by the concept of motion dynamics of a ship floating on water. This paper assumes that similar condition can occur while a train is moving straight at constant speed. Based on this assumption, the authors measured the vertical acceleration and the roll rate of moving trains, which were to be applied to D3DCG for trains, and were successfully able to detect 3D-locations of the center of gravity on trains by D3DCG.

著者

森山 淳

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.2536-2548, 2012 (Released:2012-07-25)

参考文献数

10

被引用文献数

3 2

---

For the clarification of the overturning behavior of railway vehicle exposed to strong cross wind, several experiments were done to study the effect of wind velocity and wind direction on the wheel unloading ratio. In this paper, the results of the experiment at a line in the Kanto region are described. In this line, strong wind is often observed, and various types of train are operated. To get useful knowledge about the improvement of the critical wind speed of vehicle overturning, data were analyzed in terms of the vehicle cross-sectional shape. Results of the experiment show that vehicle specifications, such as a car weight, or a bogie suspension are little effective for overturning, if there are no difference about the cross-sectional shape. Analyzed results of the experiment also show that depending on the cross-sectional shape, the behavior of wheel unloading ratio by strong wind is different. These results suggest the possibility of the superiority of round shape roof for improving the performance against overturning.

著者

下田 昌利 山根 滉一

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.79, no.807, pp.4353-4367, 2013 (Released:2013-11-25)

参考文献数

21

---

This paper proposes a convenient numerical form-finding method for designing the minimal surface, or the equally tensioned surface, of membrane structures with specified arbitrary boundaries. Area minimization problems are formulated as a distributed-parameter shape optimization problem. The internal volume or the perimeter is added as a constraint according to the structure type such as a pneumatic or a suspension membrane. It is assumed that the membrane is varied in the normal and/or the tangential direction to the surface. The shape sensitivity function for each problem is derived using the material derivative method. The minimal surface is determined without shape parameterization by the free-form optimization method, a gradient method in a Hilbert space, where the shape is varied by the traction force in proportion to the sensitivity function under the Robin boundary condition. The calculated results show the effectiveness and practical utility of the proposed method for optimal form-finding of membrane structures.

著者

呉 景龍 古谷 慎平 楊 家家 高橋 智

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.2062-2070, 2011 (Released:2011-05-25)

参考文献数

10

被引用文献数

2 3

---

Driver safety is an important and often sensitive issue for seniors. Statistics show that the elderly are more likely than other drivers to receive traffic citations for failing to yield, turning improperly, and running red lights and stop signs all indications of decreased driving ability. Currently in Japan, half of the deceased in traffic accidents are elderly people. In present study, we focused on how the pedal placement affect on braking action in emergency. First, ten healthy young and ten elderly individuals were asked to perform a simple reaction experiment by foot. Then, the same subjects were instructed to complete a braking action experiment with different pedal placement condition. The results suggested that both simple reaction time and foot movement time of elderly subjects were significantly longer than that of young subjects. Moreover, the brake pedal force of elderly subjects was lower than that of young subjects. Thus, aging influenced both of simple reaction time and braking action in emergency. In addition, even the pedal placement changed characteristics of braking action of both young and elderly subjects, the most comfortable pedal placement of elderly subjects differed from young subjects.

著者

田辺 郁男 ジュニオール ライムンド ダ クルス イエー トット ソー 富岡 恭平 高橋 智

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.748-758, 2013 (Released:2013-03-25)

参考文献数

16

被引用文献数

2 2

---

In the 21st century, as it is important to produce products with care for protecting the earth, a producer must be careful to conserve energy, save resources and reduce waste which pollutes environment. On the other hand, in case of a drilling, much cutting oil was also used for lubrication and cooling. This is large problem for protecting the earth. Therefore drilling technology using strong alkali water with micro-bubble was developed. A drill with through hole was used for this technology. Cooling effect of strong alkali water with micro-bubble was firstly investigated on the experiment. Then heat transfer coefficient of the drill with through hole was evaluted for cooling capacity. Tool life of the drill using strong alkali water with micro-bubble was also evaluated in the experiment of drilling using Ti6Al4V which has small thermal conductivity and is a material with difficult machining. It is concluded from the results that; (1) Cooling of strong alkali water with micro-bubble was very effectuive, (2) Heat transfer coefficient of the drill using strong alkali water with micro-bubble was 3.5 times of that of dry drilling, (3) Tool life of the drill using strong alkali water with micro-bubble was 6.5 times of that of dry drilling and 2 times of that of ordinary wet drilling respectively, (4) The drilling using strong alkali water with micro-bubble was economical and eco-friendly.

著者

鈴木 悟史 中村 俊之 吉井 正広 中島 正勝 中西 洋喜 本田 瑛彦 小田 光茂

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.4233-4248, 2013 (Released:2013-11-25)

参考文献数

11

被引用文献数

1 1

---

Generally, many space satellites have large solar array panels for power generation and large antennas for observation and communication. The panels and antennas must be lightweight because of the payload weight limit of the launch vehicle. So, they are very flexible, with little damping ability. This results in vibrations cause serious problems. When the thermal environment around a flexible structure on orbit such as a solar array panel changes to cold or hot, the flexible structure produces its own deformation or vibration. These occur most often during rapid temperature changes called thermal snap or thermally-induced vibration, which has been known to cause attitude disturbance in Low Earth Orbit (LEO) satellites. Thermal snap vibration occurring on a flexible solar array panel is very slow. It is very difficult to measure thermal snap motion by sensors such as accelerometer. The behavior of a space structure affected by thermal snap has never been observed directly in space so far. This report presents the measurement results of “IBUKI” solar array panel's behavior using monitor camera.