著者

丸茂 喜高 清水 勇介 竹内 亮佑 綱島 均 小島 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 (ISSN:21879761)

巻号頁・発行日

vol.80, no.817, pp.TL0280-TL0280, 2014 (Released:2014-09-25)

参考文献数

9

被引用文献数

1

---

This study proposes a driving assistance system to inform the notch operation timing for train drivers. The assistance system indicates visually the notch-off position where the driver releases the accelerator. The notch-off position is calculated by the present vehicle acceleration, velocity and position by assuming the constant acceleration. The assistance system also indicates the brake onset and the predicted stopping positions. Two experiments are conducted by using the train-driving simulator. One experiment examines the effects of the notch-off and brake onset timing on the vehicle velocity and the running time. The assistance system makes it possible to adjust the vehicle velocity and the running time. The other experiment examines the three running patterns by combination of the notch-off and the brake onset positions. With the time recovering pattern, which is combination of the higher notch-off velocity and the later brake onset timing, the assistance system realizes the shorter running time in comparison with the standard running pattern. With the energy saving pattern, which is combination of the lower notch-off velocity and the later brake onset timing, the assistance system prevents the time delay by the later brake timing even if the velocity is lower than the standard running pattern.

著者

岡田 光貴 末岡 裕一郎 中西 大輔 大須賀 公一

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 (ISSN:21879761)

巻号頁・発行日

vol.85, no.880, pp.19-00151, 2019 (Released:2019-12-25)

参考文献数

13

---

This paper is concerned with the demonstration of scallop-like swimming with the aid of robot toy; using jet propulsion by clapping the shells quickly. Previous works from biological approach have indicated what structures contributes to generate the jet propulsion. This paper tries to perform quick underwater locomotion by mimicking the structures of scallop based on constructive approach: development of scallop-like robot with autonomous generation of jet propulsion. After designing the structure and actuation mechanism by mimicking the scallop, we focus on the effect of the mantle property on swimming. Firstly we confirm that developed robot can perform scallop-like swimming. Secondly we also compare the swimming speed by changing the property of designed mantles.

著者

石崎 啓太 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 (ISSN:21879761)

巻号頁・発行日

vol.84, no.866, pp.18-00050, 2018 (Released:2018-10-25)

参考文献数

55

被引用文献数

2 3

---

This study systematically analyzed life cycle CO2 (LCCO2) emissions of a comprehensive set of mass-produced 2,000 cc class sedan-type vehicles, using a hybrid life cycle inventory approach. Gasoline and diesel internal combustion engine vehicles (ICEVs), hybrid electric vehicle (HEV) as well as battery electric vehicle (BEV) and fuel cell vehicle (FCV) were investigated, considering (i) the current BEV market trends, (ii) Japan's energy mix (the average for 2012–2014), and (iii) the use of the HVAC system. The results show that the annual average increment of CO2 emissions in use phase by HVAC system in Japan (assumed annual mean temperature of 15°C) was presumed to be evenly 9% regardless of vehicle types, although further detail analysis is required. The CO2 emissions in use phase of BEV were higher than those of HEV and FCV (applied hydrogen produced by steam reforming of LPG (on-site)) due to thermal power dominant electricity generation mix in Japan in recent years. As a consequence of high CO2 emissions from power supply and battery production, the LCCO2 emissions of BEV equipped with 75 kWh battery were higher than those of HEV, FCV (on-site), and conventional ICEV (diesel). By reducing the battery capacity to 40 kWh or less, the LCCO2 emissions of BEV become lower than those of ICEVs and FCV (on-site), making BEV a competitive alternative. However, it is difficult that BEV mitigates both LCCO2 emissions and driver's range anxiety. In conclusion, HEV shows the competitive performance in terms of LCCO2 emissions with long driving range in Japan.

著者

近藤 千尋 佐野 広季 一宮 暢希 山根 浩二 河﨑 澄

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 (ISSN:21879761)

巻号頁・発行日

vol.85, no.874, pp.18-00340, 2019 (Released:2019-06-25)

参考文献数

9

---

This paper describes how to produce a biodiesel fuel (BDF) from the waste soup of ramen noodles, especially focusing on the recovery process of the oil (triglycerides) from a large amount of waste soup or the oily wastewater disposed of by pouring it down the sink by a ramen restaurant. By combining a semi-transparent bucket (~6 L) with a cock and solvent extraction, it is shown that oil can be recovered easily from 300 or more bowls of ramen noodle waste soup, with an energy profit ratio (EPR) of more than 5.2. The initial cost of the bucket is about 1600 yen, so it has little effect on the price of the BDF produced from the oil in the ramen noodle waste soup, and it is shown that the increase in running cost to produce BDF by this method is about 2.3 yen/L if the rate of recovery of hexane (solvent) is over 99%, which is approximately equivalent to the production cost of waste-cooking-oil BDF production by previously reported methods. Furthermore, in the case of applying the proposed method based on the solvent extraction to the recovery of oil from the oily wastewater disposed of by a ramen noodle restaurant, it is shown that oil can be recovered from the waste soup of ramen noodles just after disposal as well as from the oily wastewater that spent one day in the grease trap. In the former case, EPR is 5.0, and the estimated amount of BDF is greater than 100 L/month for one restaurant. However, in the case of using the oily wastewater from the grease trap, EPR is less than 2.0 because of the reduction of yield of BDF due to a greater oxidation deterioration of the recovered oil, when the alkyl catalyst method is used. Therefore, it is desirable to recover oil from the oily wastewater at the drain pipe just after the sink.

著者

三浦 智 鈴木 智裕 小林 洋 藤江 正克

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 (ISSN:21879761)

巻号頁・発行日

vol.83, no.850, pp.16-00414, 2017 (Released:2017-06-25)

参考文献数

30

被引用文献数

1 2

---

Hemiplegic patients often have reduced typing speed due to finger paralysis. Our motivation is to develop a keyboard that enables their typing speed to increase. For this purpose, we have developed a three-dimensional keyboard that reduces the distance that fingers move while typing. In this paper, our objective was to construct the finger model that combines the motion speed and muscle fatigue for design of keyboard that can be typed with fast motion speed and low muscle fatigue. In experiment, we measured the finger position using a magnetic 3D motion device and EMG when the participant pressed the proposed key. The experiment was carried out in a variety of the finger postures. We qualified the motion speed and muscle fatigue at each joint angle. Then, we weighted and combined two of the objective functions. We found out the Pareto solution and get an effective keyboard design straight. In the future, we verify the typing speed and finger muscle fatigue during typing the three-dimensional keyboard that is designed based on our finger model.

著者

伊藤 史斗 長谷 和徳 内田 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 (ISSN:21879761)

巻号頁・発行日

pp.19-00191, (Released:2019-09-11)

参考文献数

15

---

The frame stiffness in a racing bicycle might influence not only toughness as the frame structure but also performance of an athlete. The purpose of this study is to clarify biodynamic relations between the frame stiffness in a racing bicycle and the physical loads of an athlete by using a forward dynamics simulation model. The human body structure was represented by the 13-rigid-links and 23-degrees-of-freedom model. Based on the theory of multibody dynamics, the frame structure was expressed by combination of 12 rigid pipes, and the frame stiffness was modeled by rotational springs at the connecting joint between the rigid pipes. Spring coefficients were changed according to the thickness of the frame pipes. The pedaling load from the crank was computed by the angular velocity and angular acceleration of the crank. Moreover, the driving force in the bicycle was additionally defined to consider the influence of the frame weight on the human joint load. The human body model was driven by the joint toques to minimize the cost function consisting of the joint loads in the human body and the driving force in the bicycle, and also to keep desired angular velocity of the crank. Validity of the simulation was evaluated by comparing the joint angles and torques with the measured ones. As for the result, the larger stiffness of the frame resulted in smaller the joint loads in the human body, and optimal stiffness would be determined by the balance between the joint loads in the human body and the driving force in the bicycle.

著者

北澤 勇気 坂間 清子 菅原 佳城

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 (ISSN:21879761)

巻号頁・発行日

vol.89, no.927, pp.23-00114, 2023 (Released:2023-11-25)

参考文献数

15

---

In recent years, there has been active development of robots that play a role in people's lives. These robots require actuators that have high responsiveness and high output force in addition to being small. Furthermore, safety and contact affinity are also required for these actuators. An actuator that can balance high responsiveness, high output, and contact affinity is developed in this study. The proposed system is a hybrid system of hydraulic and pneumatic systems. Hydraulic systems are generally used in machines that require large forces, such as construction machinery, because they have high responsiveness and high output force. However, hydraulic systems have poor contact affinity. On the other hand, pneumatic systems are used in machines that come into contact with people, such as power assist suits and massage chairs, because they have high contact affinity, although their output is inferior to that of hydraulic systems. Generally, the mixing of air bubbles into hydraulic oil is a problem. However, as the pressure increases, the rigidity of the working hydraulic oil mixed with bubbles approaches that of pure working hydraulic oil. If this characteristic is appropriately modeled and controlled, bubbles mixed into the working hydraulic oil can create a cushioning effect. Firstly, the relationship between the pressure and rigidity of hydraulic oil mixed with bubbles is demonstrated in this paper. Secondly, the mechanism of the hybrid system and the prototype model are explained. Lastly, the results of performance evaluation through analysis and experiments are presented. From these results, this paper shows that the proposed system has the potential to balance high responsiveness, high output, and contact affinity.

著者

小柳 健一 野田 堅太郎 大島 徹 増田 寛之 塚越 拓哉 桒子 嘉美 木谷 尚美

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 (ISSN:21879761)

巻号頁・発行日

vol.89, no.927, pp.23-00128, 2023 (Released:2023-11-25)

参考文献数

26

---

When mascot suits or plush fabrics are used to cover a human-friendly robot, frequent sterilization may be required, depending on the use of the robot. However, the effects of such sterilization are not sufficiently understood. In this study, variations in the strength and color values of plush fabrics were measured and quantitatively evaluated following 50 cycles of sterilization by ethylene oxide gas (EOG). The fabrics were composed of boa fabric, which is commonly used in mascot suits and plush dolls, and cloth reinforced with polyurethane foam. The tensile strength and the elongation were measured by the tensile strength test for clothes or clothing seams, in accordance with the standard JISL1096. In terms of appearance, red-green-blue (RGB) color values were obtained from photographs taken under the same light conditions to evaluate the color tone. A friction test was used to evaluate the tactile sensation. These results showed that EOG sterilization did not notably affect the properties of the fabrics; however, a single cycle of autoclave sterilization degraded the fabrics. Notably, the boa fabric shrunk and hardened. Thus, EOG sterilization, which does not feature elevated temperatures, may be an effective sterilization approach for these materials.

著者

沖野 友洋 永田 恵輔 高野 純一 小林 秀敏

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 (ISSN:21879761)

巻号頁・発行日

pp.21-00073, (Released:2021-09-17)

参考文献数

19

---

The crash safety structure of the railway vehicles is important as one of the safety measures against the train crews and the passengers in the event of a collision accident. It is impractical to perform collision testing many times using the actual train unit to design the crash safety structure, whereby the numerical simulation is effective and it is important to validate the analytical accuracy. However, there are few studies of collision tests and numerical simulations using actual size carbody structures according to Japanese design standards, and even fundamental data have not been sufficiently obtained. Therefore, firstly, the authors performed the collision test of an actual-size partial stainless-steel carbody structure of a railway leading vehicle against a rigid wall and finite element analysis under the same condition as the test for the purpose of validating and improving the analytical accuracy of numerical simulation. Secondly, we carried out the collision test of the same carbody structure of a railway leading vehicle against a typical large dump truck in Japan and obtained the fundamental data such as the time histories of the impact compression load and the acceleration of the carbody structure as well as the deformational and fractural behavior of them. We also performed FE analysis under the same condition as the experimental test and compared the numerical result to the experimental one. As a result, the numerical result was consistent with the experimental result. Finally, we expanded the partial carbody structure model to a single carbody model and carried out the collision analysis of it against a large dump truck. Thereby, the impact deformation and fracture behavior of the railway carbody under the actual level-crossing accident were estimated.

著者

鈴木 悠平 大隅 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 (ISSN:21879761)

巻号頁・発行日

vol.83, no.849, pp.17-00017-17-00017, 2017 (Released:2017-05-25)

参考文献数

11

被引用文献数

1

---

A design method of time-optimal trajectory of quadruped robots from an initial position to a target position is developed for trot gait. The designed trajectory consists of three phases, acceleration phase, steady walk phase and deceleration phase. The time-optimal trajectory is designed in each phase and they are integrated so that the robot reaches the target position. Since the fastest walk trajectory in steady walk has already been obtained in our previous research, the time-optimal trajectories in the acceleration and deceleration phases are designed in a similar way to the previous study. First, all the possible trajectories in the search space with which the velocity of the robot reaches the previously obtained maximum velocity are designed in the state space of the robot. Next, they are checked whether the physical constraints and the constraint imposed by swinging legs are satisfied or not. Then the trajectory with the shortest time to reach the maximum velocity is chosen as the time-optimal trajectory among the trajectories satisfying all the constraints. The obtained time-optimal trajectories are tested by a quadruped walking robot SONY ERS-7 and the effectiveness of the developed method of designing time-optimal trajectory is verified.

著者

品川 晃徳 野澤 久幸 内山 裕太郎

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 (ISSN:21879761)

巻号頁・発行日

vol.83, no.854, pp.17-00086-17-00086, 2017 (Released:2017-10-25)

参考文献数

4

被引用文献数

1

---

It is thought that the first step to understanding vehicle movement is to measure and analyze that movement in order to confirm that it falls within the range of the laws of physics. In the case of a four-wheeled vehicle, in general, the friction limit is defined within the circle of longitudinal acceleration and lateral acceleration through the use of a G-G diagram. Then measurements are taken to confirm that the driving state is within that range. Two-wheeled off-road vehicles are mainly ridden on slippery dirt roads that include steep slopes and rough, uneven surfaces. An analysis method for the driving state and the vehicle movement limits that would be suitable for analyzing the movement of such two-wheeled off-road vehicles under these conditions was examined. These movement limits were then formulated by taking into consideration the coefficient of friction and the road surface gradient in accordance with the basic laws of physics and also by focusing on the vehicle movement in the longitudinal direction. Measurements were also taken during actual off-road riding by top-class Japanese off-road motorcycle riders. It was confirmed that this measurement data was distributed within the range of the assumed vehicle movement limits. Consequently, it was confirmed that it is possible to use such measurements to accurately grasp the vehicle movement limits and the associated driving state for two-wheeled off-road vehicles.

著者

小西 祐一郎 堀内 敬介 西原 淳夫

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 (ISSN:21879761)

巻号頁・発行日

vol.83, no.845, pp.16-00243, 2017 (Released:2017-01-25)

参考文献数

10

被引用文献数

2 1

---

In order to reduce thermal resistance of power module system, Thermal Interface Materials (TIMs) have been used at the interface between baseplate of power module and heat sink. TIMs have an important role to reduce thermal resistances due to solid surfaces with roughness or waviness. Thermal grease is a primary candidate to fill the gap between them. The grease can be pumped out of the gap during thermal cycling while the grease has the advantages of reduced cost compared to the other TIMs and TIM’s thickness. New reliability test of the grease is required for thermal management as the pump-out phenomena cause an increase of the thermal contact resistances. This study shows a visualization test method to evaluate pump-out phenomena of the grease during thermal cycling. A bimetal plate consisting of copper and invar is used to simulate thermal deformation of baseplate in power module. The grease is filled between the bimetal plate and Al thick plate, and then thermal cycling test is conducted. A 25 MHz ultrasonic imaging is used to visualize the grease layer. The ultrasonic images show a sequence of the grease behavior after the thermal cycling. The ultrasonic imaging results indicate that voids occur in non-curing grease under repeated pressure while cracks are detected in curing grease. It is also found that the curing grease layer applied in power devices can be designed by the evaluation of initial thermal contact resistances at the interface. Sensitivity analysis of correlated factors shows pump-out phenomena are strongly affected by curing of grease.

著者

原 祥尭 坪内 孝司 大島 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 (ISSN:21879761)

巻号頁・発行日

vol.82, no.834, pp.15-00421, 2016 (Released:2016-02-25)

参考文献数

14

被引用文献数

1 1

---

We propose a new Grid-based SLAM method with partial map matching for considering previous sensor data in Rao-Blackwellized Particle Filter. The partial maps are built probabilistically as accumulated scan shapes for each particle. In conventional Grid-based SLAM methods, Rao-Blackwellized Particle Filter is often used. However, the conventional methods sometimes fall into misalignment and fail to build proper maps in large or limited visibility environments. In those environments, the sensor data becomes insufficient shape to match with maps for localization since the sensor field of view is limited. It causes misalignment and failure in localization and map building. Rao-Blackwellized Particle Filter of the conventional methods is based on a Hidden Markov Model that uses only current sensor data to estimate robot poses. Hence, if the current sensor data is insufficient, it is difficult to estimate robot poses and build maps correctly. In our new method, the Hidden Markov Model has been extended to utilize a series of sensor data from the past in several seconds to the present. The series of sensor data is accumulated to make scan shape sufficient for the matching in localization. Thus, the proposed method is expected to cover the lack of sensor field of view by means of the accumulation of sensor data, and is capable of mapping in large or limited visibility environments. In our experiments at Tsukuba Challenge 2014 and Tsudanuma Campus, consistent maps were built only by the proposed method. Shape errors of the maps built by the proposed method were smaller than the conventional method.

著者

関根 康史

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 (ISSN:21879761)

巻号頁・発行日

vol.83, no.845, pp.16-00250, 2017 (Released:2017-01-25)

参考文献数

14

---

Recently, AACN (Advanced Automatic Collision Notification) that presupposed cooperation with emergency life-saving organizations is expected. Therefore, emergency life-saving organizations must recognize injury speciation of patients, as quickly as possible. So, the author tried the traffic accident analyzing method by statistical data analysis from combing analysis items analysis items for main site of injury and analysis items for injury contents (indicated in the traffic accident statistics vote by Japanese National Police Agency). And furthermore it is necessary to improve the safety of vehicles not only for same class collisions but also for collisions between vehicles of different types (e.g., between SUVs and sedans). In this study, the author applied the method of analysis as described above for frontal collision between SUVs and middle sedans, and analyzed using statistical data stored in ITARDA (Institute for Traffic Accident Research and Data Analysis). In the case of fatal or severe injuries, it is shown that the component rate of chest fracture of middle sedan drivers is higher than that of SUVs. It is supposed that the difference in these rates is caused by the vertical offset configuration between the frames of the two different types of vehicles when they crash into each other.

著者

橘 智也 正田 浩暉 Aiza Syamimi Binti Abd Rani 野間口 大 岡本 和也 藤田 喜久雄

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 (ISSN:21879761)

巻号頁・発行日

pp.21-00222, (Released:2022-01-07)

参考文献数

21

被引用文献数

1

---

Generating novel design concepts in the conceptual design phase is a cornerstone for producing innovative products. This paper proposes a method to support the generation of new design concepts from patent documents. The proposed method is based on the theory of novelty potential that the combination of abstract concepts leads to the generation of the novel design concept and that the distance between the combined abstract concepts correlates to the possibility of generating it. This research adopts the distributed word representation model of word2vec to extract abstract concepts from patent documents and to measure the concept distance. The two matrices are introduced to visualize the relationships of the extracted abstract concepts; the novelty potential matrix which shows the value of the novelty potential between the abstract concepts, and the void matrix which shows the numbers of existing patents of the abstract concepts. They help a designer to identify the combinations of abstract concepts that are high novelty potential and no existing patent. This paper demonstrates a case study of generating novel ideas of sports business with blockchain using the proposed method. The results show its uniqueness and effectiveness.

著者

米岡 裕矢 宮田 なつき 前田 雄介

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 (ISSN:21879761)

巻号頁・発行日

pp.18-00055, (Released:2018-06-08)

参考文献数

16

被引用文献数

1

---

In this study, we measured and analyzed the degree of posture discomfort with respect to the coordinated range of motion (ROM) of the thumb. For ergonomic assessment of a product CAD model using a digital hand model, such joint properties are necessary to be clarified when estimating possible natural postures to use the product. We concentrated on the thumb, which plays an important part to form various grasps by opposition. To model range of motion considering coordination among joint variables, each subject's hand during a given set of exercises was captured by an optical mocap system. A posture of the carpometacarpal (CM) joint of the thumb was expressed with spherical coordinates to integrate different subjects' ROM easily. The result was shown some characteristics of the thumb such as coordination among joint variables or collision between thumb and other parts of the hand. The posture discomfort data was collected through the experiments for four adults with healthy hand. To control variety of the postures, each subject was asked to reproduce about 45 displayed postures and to answer whether the subject felt discomfort or not in terms of keeping that posture for 10 seconds. The discomfort experiment results were combined into a discomfort possibility map with respect to joint postures. This map can assist product design, for example considering interface layout.

著者

近藤 千尋 佐野 広季 山根 浩二 小坂田 潔 河崎 澄

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 (ISSN:21879761)

巻号頁・発行日

vol.83, no.847, pp.16-00375, 2017 (Released:2017-03-25)

参考文献数

11

被引用文献数

1

---

This paper describes how to produce a biodiesel from the oil in the waste soup of ramen noodles, and especially clarifies an amount of oil in waste soup, the energy profit ratio (EPR) of the production of biodiesel from the oil in waste soup of ramen noodles and the engine performance of the biodiesel from waste soup of ramen noodles. As a result, from the waste pig bone (ton-kotsu) soup the recovered tri-glyceride was about 11g per a soup. The biodiesel produced from the oil in the waste soup of ramen noodles by using ordinary alkyl catalyst method has low cold flow properties, due to the high content of the saturated fatty acid methyl ester such as C16:0, C18:0 and so on. And it is estimated that the amount of BDF from a ramen noodle restaurant is about 2.4L if the customers are around 300 per day, and this means that the 9.9 kW co-generation system is able to be operated for an hour per day. About energy profit ratio analysis, if the oil separation process is improved, EPR from the waste soup to biodiesel will become higher than 5.0. Furthermore, engine test is performed by using BDF from the waste soup of ramen noodles as B5. As a result, it is shown that fuel consumption rate and emissions are almost the same as the case of using gasoil.

著者

小川 渉 鞍谷 文保 吉田 達哉 小出 俊雄 水田 泰次

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 (ISSN:21879761)

巻号頁・発行日

pp.19-00237, (Released:2019-12-26)

参考文献数

10

被引用文献数

2

---

Cymbals are percussion instruments that vibrate and radiate sounds when hit with a stick. A bell is the raised section in the middle of the cymbal and its size produces different sounds. In this study, we investigate the effect of bell size on the sound characteristics of cymbals. The radiated sounds and vibrations for cymbals with two different bell sizes are measured. In addition, the natural frequency and mode shape are obtained by finite element analysis and the sound radiation efficiency is calculated for each mode. The measured results indicate that the sound frequency characteristics for the large bell show three peaks with large sound pressure within the range of 1000 to 3000 Hz and the sound pressure for the small bell is larger than that for the large bell within the range of 4000 to 5000 Hz. The vibration frequency characteristics show there is no remarkable difference between the large and small bells. The sound radiation efficiencies indicate that the large bell has many modes with high radiation efficiency within the range of 1000 to 3000 Hz and their modes have a small number of nodal diameters and a large deformation at the bell. The small bell has many modes with high efficiency within the range of 4000 to 5000 Hz. This is reason for the difference in sound characteristics between the large and small bells.

著者

品川 晃徳 野澤 久幸 内山 裕太郎

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 (ISSN:21879761)

巻号頁・発行日

pp.17-00086, (Released:2017-06-05)

参考文献数

4

被引用文献数

1

---

It is thought that the first step to understanding vehicle movement is to measure and analyze that movement in order to confirm that it falls within the range of the laws of physics. In the case of a four-wheeled vehicle, in general, the friction limit is defined within the circle of longitudinal acceleration and lateral acceleration through the use of a G-G diagram. Then measurements are taken to confirm that the driving state is within that range. Two-wheeled off-road vehicles are mainly ridden on slippery dirt roads that include steep slopes and rough, uneven surfaces. An analysis method for the driving state and the vehicle movement limits that would be suitable for analyzing the movement of such two-wheeled off-road vehicles under these conditions was examined. These movement limits were then formulated by taking into consideration the coefficient of friction and the road surface gradient in accordance with the basic laws of physics and also by focusing on the vehicle movement in the longitudinal direction. Measurements were also taken during actual off-road riding by top-class Japanese off-road motorcycle riders. It was confirmed that this measurement data was distributed within the range of the assumed vehicle movement limits. Consequently, it was confirmed that it is possible to use such measurements to accurately grasp the vehicle movement limits and the associated driving state for two-wheeled off-road vehicles.

著者

松本 光広

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 (ISSN:21879761)

巻号頁・発行日

vol.82, no.834, pp.15-00127, 2016 (Released:2016-02-25)

参考文献数

16

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A bicycle wheel consists of a hub, spokes, nipples and a rim. The rim deforms from true circle to irregular circle when a worker assembles the wheel. People can ride a bicycle in safety when the rim is the true circle. The worker needs to correct the deformed rim. The worker can correct the deformed rim through the use of a relation between a nipple position to rotate a nipple rotation angle and rim displacements. I developed a task support equipment to correct the deformed rim through the use of the relation. The worker does not need to know the relation through the use of the developed task support equipment. The worker can correct the deformed rim through the use of the developed task support equipment. The developed task support equipment shows the worker the nipple position to rotate the nipple rotation angle. The worker rotates the nipple as shown by the developed task support equipment. I measured the relation between the nipple rotation angle and the rim displacements. I suggested a method to calculate the corrected rim displacements through the use of the relation. I made up a hardware and a software in the task support equipment. I implemented the method in the software. I checked performance of the developed task support equipment. I corrected the deformed rim through the use of the developed task support equipment. The results have shown the usefulness in the developed task support equipment for correcting the deformed rim.