著者

西山 修二

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 (ISSN:21879761)

巻号頁・発行日

vol.83, no.855, pp.17-00260, 2017 (Released:2017-11-25)

参考文献数

21

被引用文献数

1

---

This research presents an experimental investigation on the vision performance of a human body which is sitting on an automobile seat. Six subjects were selected from a panel for the experimental research and frequency exposes from 1 to 30Hz sine wave vibration to the subjects by the sweep for 240 seconds with the total amplitude of 2 millimeters. The subjects were measured a standard visual acuity test and a self-rated assessment for difficulties in visual perception every 2 Hz and two subjects of them were measured vertical acceleration for their head in the experimental investigation. From the experimental result, visual efficiency was declined to 49.55 % in the vicinity of the frequency range of 20 Hz. The cause of reduction of eyesight has been considered using the model eye of Gullstrand, and it has been found that the deformation of optic-axis length was 0.257 millimeters when the average eyesight of all subjects was reduced from 1.15 to 0.57. Some results are presented in the form of parametric graphs. The results are useful for improving vehicle ride comfort, maneuverability and safety driving.

著者

西山 修二

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 (ISSN:21879761)

巻号頁・発行日

vol.83, no.855, pp.17-00228-17-00228, 2017 (Released:2017-11-25)

参考文献数

18

---

This paper descries theoretical and experimental research on mechanical behavior of a cylindrical container which is divided into multiple space of an equal size into which one cylindrical rod of the same diameter and material is enclosed. It is clarified that an explanatory variable and a criterion variable which are governed rolling movement characteristics of the cylindrical container. A rotary dumping number that is a dimensionless parameter is defined. Theoretical formulas are introduced for the cylindrical container in which one, two and numerous cylindrical rods are enclosed in none divided space of the cylindrical container. Unfixed coefficients in the theoretical formula are properly identified from experimental results practiced more than one. As a result of investigation, we have found that initial velocity from which a rotary dumping number becomes maximum value exists for the cylindrical container in which numerous cylindrical rods are enclosed in none divided space. Some results are presented in the form of parametric tables and graphs.

著者

山本 真 山本 忠 西山 修二

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 (ISSN:21879761)

巻号頁・発行日

vol.83, no.852, pp.17-00006-17-00006, 2017 (Released:2017-08-25)

参考文献数

26

被引用文献数

2

---

This paper presents theoretical research on an optimum transition curve with smoothly changing curvature using a multiple clothoid curve for improving the occupant ride comfort of automobiles. At the connecting points between an inlet straight line and a circular arc, or between a circular arc and an outlet straight line, vehicles cannot run smoothly owing to the discontinuity of curvature. Especially, the vehicles equipped with a driving support device which assists driver's steering operation or performs steering operation instead of a driver will increase both unstable movement of vehicle and discomforts of occupant. Moreover, the discontinuity of curvature in the connecting points makes the control of advanced accuracy of apparatus difficult. In order to solve such problems, three dimensional vehicle occupant model which is 21 degrees of freedom is assembled, and the multiple clothoid curve is proposed as a new transition curve. The validity of the multiple clothoid curve is shown as compared with the case where it is interpolated by a single clothoid curve or by a non-interpolation. It was found that the influence of the multiple clothoid curve on vehicle movement and ride comfort is superior to those of the single clothoid curve or the non-interpolation. Some results are presented in the form of parametric plots.

著者

西山 修二

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 (ISSN:21879761)

巻号頁・発行日

vol.83, no.849, pp.16-00353-16-00353, 2017 (Released:2017-05-25)

参考文献数

13

被引用文献数

1

---

This paper descries the experimental research about the rolling resistance performance of a cylindrical container which is divided into multiple space of equal size into which numerous cylindrical rods of the same diameter and material are enclosed. We have investigated the effect of a diameter of the cylindrical container, a number of wall surface division of inside of the cylindrical container, a diameter of a cylindrical rod and a filling rate on the rolling resistance performance. The three cylindrical containers have a diameter of 48, 60 and 76 millimeters and a length of all 100 millimeters. Each of the cylindrical containers is divided into zero, two, four and six space. The three cylindrical rods are 3, 4 and 5 millimeters in diameter. Three kinds of the filling rate which is the ratio between inside cross sectional area of the cylindrical container and total cross sectional area of the cylindrical rods enclosed in the cylindrical container are investigated. And in the experiment, both initial velocity and a rolling distance of the cylindrical container are measured. As the results of investigation, we have defined new dimensionless parameter, that is a roller dumping number which is the ratio between deceleration of the cylindrical container and the gravity acceleration, and it is shown that the kinematical and dynamical performance of the cylindrical container with the cylindrical rods is largely depend on this parameter. According to the research results, it is found that the diameter of the cylindrical container, the filling rate and the number of wall surface divisions have a substantial influence on the roller dumping number. Some results are presented in the form of parametric tables and graphs.