著者
金城 孝俊 青木 岳史
出版者
公益社団法人 日本設計工学会
雑誌
設計工学 (ISSN:09192948)
巻号頁・発行日
vol.54, no.2, pp.111-122, 2019 (Released:2019-02-05)
参考文献数
16

When using robots to investigate a disaster site after an earthquake, the act of carrying robots into the workplace is dangerous for the rescuer and may result in a second accident. If robots can be thrown into the workplace, operators will be safe and the job made easier. We have been researching and developing our legged robots "QRoSS" series, which are transformable robots with a spherical outer shell to absorb the external shock of landing. The purpose of this study is the development of QRoSS III, which can get over obstacles by jumping. It performs two takeoff postures and two static gaits using three legs and its shell. This paper reports concepts and the design of QRoSS III and discusses experimental results: takeoff postures, gait locomotion and a series of the jumping motions.
著者
野口 昭治 小川 康介
出版者
公益社団法人 日本設計工学会
雑誌
設計工学 (ISSN:09192948)
巻号頁・発行日
pp.2015.2674, (Released:2016-03-25)
参考文献数
8

Roller chains are applied in two wheels, constructing machine and agricultural machine as the power-transmitting means. Compared with a belt as a winding transmission device, chain transmission is of advantage in transmission efficiency and capability. However, there is a problem of elongation caused by wear between pin and bush, which make flexion movement. Generally to decrease the wear, although a certain additive agent such as wear inhibitor is mixed with lubricant, the advantageous effect does not exist for very long time. Because the side surfaces of pin and bush are opened up to the air. Our past result presents that the contact between pin and bush occurs only at the both ends of the pin. On the basis of this resultant, the authors dealt with the possibility of decrease of wear by reducing contact surface pressure with enlarging the contact area between pin and bush. Then, crowning process to reduce edge load in cylindrical roller bearing was experimented. Furthermore, an optimized design, to enlarge the contact area by means of FEM analysis with considering the deformation of bush due to the press fitting, was also studied. Consequently, in this research, the decrease of wear depth by enlarging the contact area was verified by some experiments.
著者
吉田 昌央 中島 公平 石河 開
出版者
公益社団法人 日本設計工学会
雑誌
設計工学 (ISSN:09192948)
巻号頁・発行日
pp.2016.2679, (Released:2016-06-09)
参考文献数
8

For an air-cooled engine, designers must choose the number of fins required for cooling, then arrange them along the cylinder at a suitable fin pitch. Most motorbikes mount their air-cooled engines at a slant, with their cylinder centralaxis not perpendicular to the air flow. This study investigated the cooling characteristics of air-cooled experimental cylinders, with various fin pitches and number of fins, mounted at tilt angles between 0°(vertical) and 90°(horizontal),in a wind tunnel at air velocities of 20km/h (5.6m/s) and 60km/h (16.7m/s). Heat release from the cylinder was measured, air flow between fins was observed using the smoke wire method, and air flow over fin surfaces wasobserved using the oil film method. Results indicated that, except at 20km/h (5.6m/s) and a pitch of 7.5mm, cylinder cooling increased as tilt angle increased from 0° to 40°, then decreased when the cylinder tilt angle exceeded 40°. Only at 20km/h (5.6m/s) and a pitch of 7.5mm, cylinder cooling increased as tilt angle increased from 0° to 30°, then decreased when the cylinder tilt angle exceeded 30°. Cylinder cooling was maximized with 7 fins pitched at 10mm.
著者
中 尚義 橋本 巨
出版者
公益社団法人 日本設計工学会
雑誌
設計工学 (ISSN:09192948)
巻号頁・発行日
vol.51, no.11, pp.788-801, 2016 (Released:2016-11-05)
参考文献数
24

Dragonflies have high flight performance in spite of small size. Therefore, the research of clarifying the flight mechanisms of dragonflies, and then applying it to Micro Air Vehicles (MAVs) is proceeding. Dragonfly's flight mainly consist of a flapping motion and a feathering motion. To control the MAV like dragonflies, clarifying the effect of the flapping motion and the feathering motion on generating aerodynamic force is necessary. In this study, lift and thrust force generated by flapping were measured using flap simulator adjusted the flapping and feathering angle. As a result, lift and thrust force were increased with increase in the flapping angle. Thrust force was particularly increased with increase from 30° to 40° in the flapping angle. When the feathering angle is 45°, downforce was very small, and a lift fluctuation was small. Therefore, the feathering angle of 45° are suitable for the straight flight. When the feathering angle is 60°, momentary lift force was very high. Therefore, the feathering angle of 60° are suitable for a climbing flight such as the take-off. In fact, it was confirmed by the motion analysis that the feathering angle of a dragonfly in the take-off is 60° or more.
著者
荒川 俊也 杉森 順子
出版者
公益社団法人 日本設計工学会
雑誌
設計工学 (ISSN:09192948)
巻号頁・発行日
vol.53, no.3, pp.237-250, 2018 (Released:2018-03-05)
参考文献数
18

This study examines the effect of manufacturing education on mechanical engineering students using an art work based on design thinking. The miniature movable monument of “flexible dimension (by Junko Sugimori)” is developed. Based on many real-monument pictures and the outline of the miniature monuments created using 3D printer, a basic model of miniature monuments is created. To move the miniature monument, the motion data of the finger was captured via Leap Motion technology and the data was transmitted via XBee processing and the angle of rotation was calculated. From this project, which discusses miniature monument development, students learned about the relation between manufacturing and art based on design thinking.
著者
加藤 恵輔 中村 祐介 長谷川 一樹 根崎 雄太
出版者
公益社団法人 日本設計工学会
雑誌
設計工学 (ISSN:09192948)
巻号頁・発行日
vol.55, no.2, pp.117-128, 2020 (Released:2020-02-05)
参考文献数
19

Promotion of barrier-free systems has been discussed actively because of the recent aging society, and more and more elevators and other devices have been installed in places such as large-scale public facilities and stations. However, it is difficult to apply barrier-free designs to every building to assist people’s mobility and smooth carriage of luggage. Especially stairs are the challenging place in terms of mobility. We consider a vehicle-type robot that can go up and down stairs is effective to solve this problem. Thus, in our study, we aimed to establish a technology which prevents the robot from sliding down stairs, and we proposed the wheel structure with the new C-shaped claw mechanism to adapt passively to shapes of steps. We also proposed the movement action principle that is less affected by the distance between the stair nosings. In this paper, we discuss the mechanical configuration and the mechanical design of the vehicle-type robots that we have developed, and report on the experiments.
著者
米田 完 青山 雅規 浦 広幸
出版者
公益社団法人 日本設計工学会
雑誌
設計工学 (ISSN:09192948)
巻号頁・発行日
vol.55, no.4, pp.263-276, 2020 (Released:2020-04-05)
参考文献数
25

An omnidirectional mobile vehicle created with Mecanum wheels does not easily negotiate stepped terrain, because the small slanted freely moving wheels in the Mecanum wheel rotate at the step edge and cannot obtain a grip sufficient for climbing. We developed two types of driving wheel mechanisms based on the Mecanum wheel. One is a hybrid that combines a larger grouser wheel with a smaller Mecanum wheel with a synchronized peripheral velocity and vertically adjustable central shaft. The other comprises a split Mecanum wheel where the halves shift back and forth. The radius of the grouser wheel hybrid must be carefully designed so that the grouser can produce an adequate grip at a low position for reliable transition to the frictional grip of the Mecanum wheel. Similarly, for the split Mecanum wheel, the horizontal shift distance must be carefully determined so that the grip of the edge of one half is maintained until an adequate grip can be obtained by the other half of the wheel. Experimental robots were built with Mecanum wheels 152mm in diameter to demonstrate both wheel types. These robots showed good performance by negotiating a 100mm step (grouser type) and a 70mm step (split type).
著者
藤 智亮 立石 憲治
出版者
公益社団法人 日本設計工学会
雑誌
設計工学 (ISSN:09192948)
巻号頁・発行日
vol.52, no.4, pp.217-228, 2017 (Released:2017-04-05)
参考文献数
25

In this study, an electric swinging crib was designed to calm crying babies by giving them comfortable swinging stimuli. In addition, the authors examined and verified the usefulness of the designed crib comparing with an existing type of electric baby rack. To test our design, an experiment was carried out with 6 two month old babies at Kyushu University. In the experiment, after crying continuously for 30 seconds, the 6 babies were exposed to two different cases of swinging stimuli, as well as ‘no stimuli’ case for 4 minutes. The two cases of swinging stimuli were as follows; ‘Swing I’ (the swing by the proposed crib), and ‘Swing A’ (the swing by an existing baby rack). Babies calming responses were assessed with both behavioral and physiological indices. Regarding behavioral indices, the results showed that both ‘Swing I’ and ‘Swing A’ were effective to calm babies’ down. As for physiological indices, we analyzed the result of each baby’s heart rate and found out a possibility that ‘Swing I’ is more effective than ‘Swing A’. Furthermore, a declaration result by each baby’s mother also showed the possibility that ‘Swing I’ is more effective than ‘Swing A’.
著者
山崎 祐亮 北山 哲士 高野 昌宏 合葉 修司
出版者
公益社団法人 日本設計工学会
雑誌
設計工学 (ISSN:09192948)
巻号頁・発行日
pp.2017.2784, (Released:2018-06-27)
参考文献数
15

In plastic injection molding (PIM), warpage should be minimized for high product quality whereas cycle time should also be minimized for high productivity. Process parameters such as melt temperature, packing pressure, and cooling time strongly affect both the product quality and the productivity, and it is important to determine the optimal process parameters. This paper proposes a method to determine the optimal process parameters for the warpage and the cycle time minimization. Variable packing pressure profile that the packing pressure varies during the packing phase is adopted. Three dimensional cooling channel is also used for the warpage and cycle time minimization. Numerical simulation in the PIM is so intensive that a sequential approximate optimization is used to identify the pareto-frontier. Based on the numerical result, the experiment using the PIM machine is carried out. Through the numerical and experimental result, it is confirmed that the proposed approach is valid to the warpage and the cycle time minimization.
著者
荒川 俊也 杉森 順子
出版者
公益社団法人 日本設計工学会
雑誌
設計工学 (ISSN:09192948)
巻号頁・発行日
pp.2017.2746, (Released:2017-11-10)
参考文献数
18

This study examines the effect of manufacturing education on mechanical engineering students using an art work based on design thinking. The miniature movable monument of “flexible dimension (by Junko Sugimori)” is developed. Based on many real-monument pictures and the outline of the miniature monuments created using 3D printer, a basic model of miniature monuments is created. To move the miniature monument, the motion data of the finger was captured via Leap Motion technology and the data was transmitted via XBee processing and the angle of rotation was calculated. From this project, which discusses miniature monument development, students learned about the relation between manufacturing and art based on design thinking.
著者
藤本 滋 今井 健嗣 一木 正聡
出版者
公益社団法人 日本設計工学会
雑誌
設計工学 (ISSN:09192948)
巻号頁・発行日
vol.52, no.9, pp.567-582, 2017 (Released:2017-09-05)
参考文献数
17

Electrical power generation devices that use piezoelectric lead zirconate titanate (PZT) have been developed to convert mechanical energy given by structural vibration into electrical energy. This paper describes an analytical and experimental study conducted to clarify the power-generation characteristics of the laminated PZT element doped with Nb 1.0 mol% under vibration loads and to examine optimal layer number of the laminated PZT element. In the analytical study, theoretical formulas on the power generation characteristics of the PZT element under the vibrational loads are derived by considering the equivalent circuit model consisting of the laminated PZT element. Optimal layer number deduced from the theoretical formula is 11 layers, and 11-layers PZT elements are produced in order to investigate the power-generation characteristics. In the experimental study, the effects of the number of layers of the laminated PZT element, the loads and frequencies on the power-generation characteristics of the laminated PZT element are evaluated by vibration tests. The experimentally obtained results are in good agreement with the values obtained theoretically and the validity of the theoretical formulas to vibration force of the laminated piezoelectric element was confirmed. Further, the optimal layer number of the laminated PZT element is confirmed to be 11 layers.
著者
田中 好一 平田 克己 伊澤 悟 堀 三計
出版者
公益社団法人 日本設計工学会
雑誌
設計工学 (ISSN:09192948)
巻号頁・発行日
vol.52, no.1, pp.41-50, 2017 (Released:2017-01-05)
参考文献数
8

The handbell that enjoys performing the bell as a percussion instrument in the group is performed actively in the school, in the church, and in the community circle. Moreover, it is paid to attention as the music therapy. However, many of marketed hand bells are made of the bronze. So, the hand bell in the bass region becomes large, heavy, and expensive. Everyone can not readily enjoy. The researchers study to make the hand bell that is suitable for the purpose of use such as light, easy to use, and comparatively cheap. We also study the suitable material for the use of the hand bell. In the present study, the influence of the processing error on the pitch has been shown using the self-made handbell of pitch of C#7.
著者
陳 献平 綿貫 啓一 楓 和憲 大谷 成子
出版者
公益社団法人 日本設計工学会
雑誌
設計工学 (ISSN:09192948)
巻号頁・発行日
pp.2015.2675, (Released:2016-05-19)
参考文献数
17
被引用文献数
1

The on-screen keyboard is widely used for text input in mobile devices such as smart phones and tablets. However, the screen area of such devices is not sufficiently wide for smooth input and poses a difficulty to users. Therefore, this paper proposes a gesture-based text entry method that is based on the property of Japanese Hiragana-50-phonemic-table with two-step finger gesture sequence. The first step gesture is to specify the row, such as “a ka sa ta na”, and the second is to specify the column, “a i u e o”. This method does not require a predetermined input area and can be used anywhere on the screen surface. We conducted experiments with ten test subjects who were accustomed to conventional flick entry and found that the proposed method was easy to learn. The input speed was estimated to about half the speed of the flick entry method. This can be attributed to the need for one stroke in flick entry based on-screen keyboards, while the proposed method requires two strokes. Further, the entry rate accuracy was observed to be 91.5%. The experimental results show that the proposed method is practically applicable as a new text entry method.