著者
野中 朋美 中野 冠
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.783, pp.4024-4033, 2011 (Released:2011-11-25)
参考文献数
14
被引用文献数
4 4

The paper proposes a carbon taxation scheme using life cycle assessment (LCA) for clean energy vehicles (CEVs). This taxation scheme can enable to be discussed tax amount, tax revenue and total CO2 emissions by changing the scenarios and parameters, such as: technology development, energy price and total driving distance. The authors figure out the tax rate 28.05[JPY/kg-CO2], which makes the hybrid electric vehicle's life cycle cost (LCC) less than that of conventional gasoline vehicles. The simulation results show that LCC after taxation of electric vehicles (EVs) have lowest total cost when battery cost is 0.14 times the 2007 cost and have lower total cost than that of GVs when driven more than 221,600 km. In addition, EVs have lowest emissions when driven more than 63,000 km considered CO2 emissions in the manufacturing phase, and it is expected that elders who drive shorter distances are best suited for hybrid electric vehicles and gasoline vehicles not electric vehicles considering LCCO2. The proposed tax system can provide consumers with an incentive to choose vehicles with lower CO2 emissions.
著者
堀畑 聡 新家 光雄 野崎 隆宏 赤堀 俊和 鈴木 亨 曽根 圭司 庭田 俊一 福田 徳久
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.79, no.803, pp.2240-2249, 2013 (Released:2013-07-25)
参考文献数
6

Traditionally, the metal mouthpieces of trumpets have been generally made of brass. However, for musicians who suffer from metal allergies, the use of the mouthpiece sometimes lead to inflammation of the lip if they are taking part in a long performance. This problem can be solved by using allergy-free pure titanium (titanium) and its alloys as the material for the mouthpiece. Therefore, a titanium alloy composed of non-toxic and allergy free elements has been designed. However, because their heat conductivity is generally poor, and they contain α phase with its HCP (hexagonal closed packed structure having structure, which restrict slip systems, forming them into suitable shapes can be very difficult. Therefore, precision casting method, where only final finishing was conducted by machining, applied for fabricating the mouthpieces of trumpets. Important considerations for use in musical instruments are the material characteristics and the sound characteristics of mouthpieces made of titanium alloy. Research on the material characteristics of titanium alloy mouthpieces is currently being undertaken. On the other hand, the sound characteristics of mouthpieces made of titanium alloy have not been examined sufficiently. In this study, the sound and the vibration characteristics of two kinds of mouthpieces made of titanium and Ti-Nb was examined. The adaptability of these materials for use in mouthpieces of trumpets was discussed by comparing the sound characteristics of mouthpieces of trumpets made of titanium, Ti-Nb, and brass.
著者
山田 貴志 渡辺 富夫
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:18848354)
巻号頁・発行日
vol.79, no.807, pp.4340-4344, 2013 (Released:2013-11-25)
参考文献数
5
被引用文献数
1

In this study, we analyzed facial expressions during muscle strain using a head mounted display (HMD)-based virtual arm wrestling system designed for facial electromyography measurement. We found that facial expressions during muscle strain are characterized by tension of the corrugator supercilii and zygomaticus major muscles. In addition, facial expressions of laughter, anger, and fear, and those during muscle strain can be distinguished based on the active pattern of the corrugator supercilii and zygomaticus major muscles. These findings are useful in the evaluation of emotions based on facial expressions during muscle strain using the HMD-based virtual reality system.
著者
桜井 康雄 鈴木 教之 饗庭 健一 吉成 考正 川島 清隆 木原 和幸
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:18848354)
巻号頁・発行日
vol.78, no.788, pp.1163-1169, 2012 (Released:2012-04-25)
参考文献数
4

In this paper, a component restricting pressure change caused by oil temperature change is proposed. One of the merits of an oil-hydraulic system is to keep the value of oil pressure when pressurized oil is enclosed in a container. However, it is impossible to keep the value when the temperature of the oil is changed. Using a pressure control sub-system to prevent it, the whole system becomes complicated. In addition to it, the energy is consumed when the pressure is adjusted by the quantity of the oil flowing into or out the container. From these view points, it is effective to develop the component which prevents the pressure change according to the oil temperature change without the control of the quantity of the oil. Therefore, in this paper, a component to prevent the pressure change based on the oil temperature change is proposed to make the merit of oil-hydraulic system certain when the temperature of the oil is changed. And, in the cases where the temperature of the oil is increased and where the temperature of the oil is decreased after it is increased, the basic characteristics of the component investigate experimentally.
著者
山田 和明 大倉 和博
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.2950-2961, 2012 (Released:2012-08-25)
参考文献数
17

Reinforcement learning approaches attract attention as the technique to construct the mapping function between sensors-motors of an autonomous robot through trial-and-error. Traditional reinforcement learning approaches make use of look-up table to express the mapping function between the grid state space and the grid action space. However the grid size of the state space affects the learning performances significantly. To overcome this problem, many researchers have proposed algorithms using neural networks to express the mapping function between the continuous state space and actions. However, in this case, a designer needs to appropriately set the number of middle neurons and the initial value of weight parameters of neural networks to improve the approximate accuracy of neural networks. This paper proposes a new method to automatically set the number of middle neurons and the initial value of the weight parameters of neural networks, on the basis of the dimensional-number of the sensor space, in Q-learning using neural networks. The proposed method is demonstrated through a navigation problem of an autonomous mobile robot, and is evaluated by comparing Q-learning using RBF networks and Q-learning using neural networks whose parameters are set by a designer.
著者
武田 雄策 大黒谷 陽子 村瀨 健二 大坪 智範 橋本 悟 伏見 亮 民谷 謙
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.4039-4046, 2013 (Released:2013-11-25)
参考文献数
10
被引用文献数
1

This paper discusses a design methodology of vehicle interior layouts and shape matching visual space KANSEI characteristics considering human visual direction perception. Relationships between perception and KANSEI of direction need to be quantified for the vehicle interior design based on multidisciplinary optimization among the KANSEI evaluation values of human visual direction and the other vehicle performances. Experiments were carried out for some interior layouts and shapes, which were displayed by immersive virtual reality system, with some subjects who develop the vehicle interior package. And, KANSEI evaluation values were measured by visual analog scale method for recording continuously. Experimental results demonstrate that the perception and KANSEI of direction have changes like sigmoid curve according to layouts and shapes. Also, KANSEI response surface, which was derived by using linear basis function models for expressing its characteristics, was applied to the A pillar design study.
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

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
井上 剛志 高木 賢太郎 竹崎 勇輝 石川 昌義
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.789, pp.1680-1690, 2012 (Released:2012-05-25)
参考文献数
7

The gyroscopic exercise tool which utilizes the gyroscopic effect caused by the whirling motion of the high speed rotating body to train the hand muscle is considered. This tool utilizes the contact phenomenon between the rotor and the case. When the input motion with 3-5 Hz is added to the case, the rotor spins in thousands rpm whirling with the precession motion which is synchronous to the input case motion. Conventional studies on this tool have assumed the continuous rolling motion of the rotor to the case. This paper does not set this assumption, and investigates the dynamical modeling of this tool considering the contact/non-contact conditions and the slip between the rotor and the case. Two kinds of motions are observed in the numerical simulation, one is the uniform precession which was observed in the conventional studies and the other is the periodically reverse precession. These two motions are physically explained, and are also observed in the experiment.
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
赤間 淳貴 福岡 泰宏 森 善一 城間 直司 井上 康介 中野 博民
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.782, pp.3808-3817, 2011 (Released:2011-10-25)
参考文献数
23

In this paper, we try to achieve biomimetic biped walking of a dinosaur-like robot, focusing on its nervous system as well as its mechanism. We have been developing a dinosaur robot “Raptetsu” based on the studies of dinosaurs on archaeology and also apply typical biomimetic locomotion control methods used for existing vertebrates for the robot. In detail, we utilize a CPG (Central Pattern Generator), which is a locomotion rhythm generator that exists in vertebrates' spinal cord, to generate the robot's walking rhythm. Moreover, reflex centers is set below the CPG in the spinal cord and produce joint torque of two legs in the swing and stance phases. Thus, we hope to produce an adaptive dynamic walking generated by interaction between the original mechanism of dinosaurs and existing animals' nervous system and try to contribute to the understanding of dinosaurs' locomotion on archaeology by observing and analyzing the dynamic walking experimental results.
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 7

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
川副 嘉彦 武田 幸弘 中川 慎理 Federico CASOLO 友末 亮三 吉成 啓子
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.4994-5009, 2013 (Released:2013-12-25)
参考文献数
13

The lightweight racket with handle-light configuration and large head size is recent tendency of high-tech tennis rackets, increasing power or post-impact ball velocity with an increasing racket swing speed. This paper investigated the performance of lightweight balanced racket with super-large head size with 120 square inches in terms of feel or comfort. It predicted the effect of the mass and mass distribution of super-large head sized rackets on the impact shock vibrations of the racket handle and the player's wrist joint when a player hits a flat forehand drive. The prediction is based on the identification of the racket characteristics, the damping of the racket-arm system, equivalent mass of the player's arm system and the approximate nonlinear impact analysis in tennis. A lightweight balanced racket (mass: 292 g, the center of gravity LG: 363 mm from the butt end) and a conventional weight and weight balanced racket (349 g, LG: 323 mm) are selected as representatives. These two super-large head sized rackets made of carbon graphite have the same head size and same geometry. The result showed that the shock vibration of the lightweight balanced racket with super-large sized head is much larger than that of the conventional weight balanced type racket. It also showed that the sweet area of the former in terms of the shock vibration shifts from the center to the topside on the racket face compared to the latter. This is because the location of the grip on the racket handle is further from the location of the node on the handle of the first mode of lightweight balanced racket than that of the conventional weight balanced racket.
著者
中村 恭子 吉谷 明敏 清水 伸二 坂本 治久
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.79, no.807, pp.4389-4399, 2013 (Released:2013-11-25)
参考文献数
10
被引用文献数
1 1

The contact stiffness of joints has been evaluated experimentally and the method quantifying them has been proposed by authors. However it was found out that the range of application for this method was limited, since the method was based on the assumption that the relationship between force and real contact area of the joint is linear. Therefore, in this paper, we consider a widely applicable and more general identification method of the contact stiffness which can be applied to the joints in which the relationship between the force and the real contact area shows non-linear characteristics. As a consequence, following results are obtained. (1) The model of the joint interface with surface roughness can be made as a surface covered by springs with same length and spring constant along the profile of surface roughness. (2)The identification method of the contact stiffness of the joint based on the model can be applied to the joints, even if the relationship between the force and the real contact area of the joints is non-linear. (3) The contact stiffness per real contact area k shows constant regardless of the applied force in the joint where the relationship between the force and the real contact area is non-linear.
著者
滝田 好宏 ブイクワン ズン 伊達 央
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.3278-3289, 2011 (Released:2011-09-25)
参考文献数
18
被引用文献数
1

This paper proposes SSM(Sensor Steering Mechanism) for a lateral guided vehicle with an articulated body which has an arbitrary position of articulation joint. The last paper shows the SSM for an articulated vehicle with a bending joint located at the center of its wheel base. The articulated robotic vehicle with SSM is demonstrated an accurate line following at low speed and a drift cornering at high speed moving. This paper discuses the SSM for the arbitrary position of articulated joint and the simple relation is derived for the lateral guided method for the articulated vehicle. In order to demonstrated the advantage of this method, an experimental vehicle is developed and tested on the evaluation course which is used previous papers. Dynamical simulations of experimental vehicle are preformed and the data is compared with the experimental data. These results demonstrate that a SSM for articulated vehicles achieve at high speeds and maintain stability on a test course.
著者
五福 明夫 単 万里 柴田 光宣 山西 輝裕 亀川 哲志
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:18848354)
巻号頁・発行日
vol.77, no.778, pp.2400-2406, 2011 (Released:2011-06-25)
参考文献数
13

This study develops a mixing machine driven by a spherical motor that can rotate around any axis. The developed mixing machine is composed of a rotor, a stator, a control PC, an electro-magnet excitation circuit, and a power supply. The rotor that its outer diameter is 200 [mm] is composed of double spherical shells in order to contain liquid in its inner spherical shell. Totally 91 permanent magnets are arranged in almost spherical symmetry on the inner surface of the outer spherical shell. On the other hand, 80 electro-magnets are arranged on the stator of a semi-spherical shell. The applicability of the mixing machine to material production under the condition of small influence of gravitational force is evaluated by mixing experiments to dissolve salt of 50 [g] in water of 200 [g]. The mixing performance is compared for five mixing methods. The results show that the mixing performance of the method to change randomly the rotation direction is only slightly lower than that of the method of rotating continuously around a horizontal axis that exhibits the highest mixing performance.
著者
藤田 貴行 塚本 哲 多田 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.77, no.780, pp.3017-3024, 2011 (Released:2011-08-25)
参考文献数
35
被引用文献数
2

1/f noises, the power spectrum density (PSD) of signals inversely proportional to the frequency, have been observed in various types of physical and physiological systems; e.g. current and heart beat. 1/f noise is suggested to be generated by superimposing stochastic processes. Among stochastic processes, autoregressive process is suitable for analyzing physical and physiological systems in that the autoregressive process is time-discrete. A time-discrete model is suitable for analyzing those systems because those systems are observed in time-discrete manner as well. However, it is obscure whether 1/f noises are generated by superimposing those autoregressive processes. In this study, first order autoregressive (AR(1)) processes were superimposed with varied the process parameter and a driving noise. As a result, PSD of superimposed time sequences was inversely proportion to the frequency when the process parameter and a driving noise were a uniformly distribution and white noises, respectively. This result suggests that 1/f noises could be generated from the superimposing AR(1) processes when the process parameter is distributed uniformly.
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 2

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
上野 祐樹 北川 秀夫 柿原 清章 寺嶋 一彦
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.78, no.789, pp.1872-1885, 2012 (Released:2012-05-25)
参考文献数
11
被引用文献数
4

Holonomic omni-directional mobile robots are very useful at narrow or crowded areas because of their high mobility performance, and omni-directional mobile robots equipped with normal tires are desired for their ability to surmount the difference in ground level as well as their vibration suppression and ride comfort. Up to the present, the caster-drive mechanism using normal tires has been developed to realize a holonomic omni-directional mobile robot, but some problems have been left. In this paper, we present an effective system to control the electric caster-drive wheel of omni-directional mobile robots, Differential Drive Steering System (DDSS) using differential gearing is proposed to improve the operation ratio of motors. The proposed DDSS generates the driving and the steering outputs effectively from utilizing two motors. Simulation and experimental results show that the proposed system is effective for both of the mobility and energy saving.
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

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.