[en] Not so long ago a new observation about rolling motion was described: for a rolling wheel, there is a set of points with instantaneous velocities directed at or away from the centre of the wheel; these points form a circle whose diameter connects the centre of the wheel to the wheel's point of contact with the ground (Sharma 1996 Eur. J. Phys. 17 353-6). We provide a detailed experimental verification of this observation, collecting 3D data from a rolling wheel with a commercially available optical tracking system. We also extend the observation to a generalized form: for a rolling wheel, there is a set of points with instantaneous velocities directed at or away from any point P; these points form a circle whose diameter connects the point P to the wheel's point of contact with the ground. This generalization is also verified experimentally

[en] In this research, a outdoor wheel-type walking-assist device is developed to help an elder having a poor muscular strength at legs for walking, sitting and standing up easily at outdoors, and also for going and downing stairs. In conceptually designing, the environments of an elder's activity, the size of an elder's body and a necessary function of helping an elder are considered. This device has 4 wheels for stability. When an elder walks in incline plane with the proposed device, a rear-wing is rotated to keep the supporting device horizontal, regardless of an angle of inclination. A height-controlling device, which can control the height of the supporting device for adjusting an elder's height, is varied vertically to help an elder to sit and stand-up easily. Moreover, a outdoor wheel-type walking-assist device is conceptually designed and is made. In order to design it, the preview research is investigated firstly. On the basis of the proposed walking-assist device, the outdoor walking-assist device is designed and made. The outdoor wheel-type walking-assist device can go and down stairs automatically. This device go up and down the stair of having maximum 20cm height and an angle of 25 degrees with maximum 4 sec/stairs speed, and move at flatland with 60cm/sec speed

[en] The development of the radial strain component in railway wheels was investigated by neutron diffraction. In the as manufactured state four railway wheels were investigated. In all four wheels no significant strains were found. After 18,400 km usage first strain gradients close to the outer surface of the wheels were detected. In axial middle ranges the changes in strain are weak. After an usage of 61,000 km the gradients becomes strong at the axial outer position between about +700 με close below the tread and -500 με in a depth of 12.5 mm below the tread. At axial middle positions also strain gradients are formed. The end of live state (510,000 km) differs only slightly from the state measured after a usage of 61,000 km

[en] The proportional pressure control valve having versatile functions and higher performance is an essential component in the open loop controlled rear wheel steering gear of the four wheel steering system on a passenger car. In this study, the authors suggest a new type of load pressure feedback mechanism which can make it easy change the control range of load pressure without changing the capacity of solenoid. The concept of the suggested mechanism, composed of the pressure chamber with throttles in series, was described. The mathematical model was derived from the rear wheel steering gear system consisting of a valve and a cylinder for the purpose of analyzing the valve characteristics. And the programme for computing the characteristic of the valve was developed. Experiments were carried out to confirm the performance of the valve and computations were performed to ascertain the usefulness of the developed programme. The results from the computations fairly coincide with those from the experiments. The results from the experiments and computations show that the performance of new valve is as good as that of the already developed one and the new valve has an advantage in the easiness in varying the control range of load pressure

[en] The removal of metal during reverse motion of the grinding wheel at extreme cross sections of holes in the workpiece during internal grinding is considered. In a single double pass of the wheel, the vibration of the contact area and the cutting forces are found to be significantly different in reverse motion within input and output holes. That disrupts the stability of metal removal and the machining precision over the length of the hole being machined. Approaches to the modeling of internal grinding with reverse motion of the grinding wheel are considered.

No abstract available

[en] This paper introduces a robot called the MRINSPECT V (Multifunctional Robotic crawler for INpipe in-SPECTion V) for the inspection of pipelines with a nominal 8-in inside diameter. Based on the mechanism of the previous model MRINSPECT IV, we developed a new MRINSPECT V by using the differential driving mechanism, so that just simply controlling the speed of each driving units helps the robot to travel effectively inside the pipelines. Furthermore, the robot uses clutches in transmitting driving power to wheels. This clutch mechanism enables MRINSPECT V to select the suitable driving method according to the shape of pipeline. In this paper, the critical points in design and construction of the proposed robot are described with the preliminary results to provide good mobility and increase the efficiency

No abstract available

[en] In this paper we study the problem of optimal control of a rigid body damping rotation with the help of three fly wheels taking into account the wheel friction. Given a quadratic performance index we seek reaction wheels that minimize it and asymptotically stabilize a rigid body rotation around the Euler axis. The damping rates of the angular velocity of the body are obtained. Many of special cases are obtained from the deduced results. Numerical simulation of the obtained results is presented

[en] The subsurface damage of ground K9 specimens and the damage mechanism are studied in this paper. Subsurface damage prediction method and step-by-step etching method are used to measure subsurface damage depth. In addition, cutting depth, feed rate and wheel speed are discussed about the influences on subsurface damage depth. Studies show that, step-by-step etching method is intuitive and effective. For the K9 specimens ground by ourselves, under the experimental conditions in this paper, subsurface damage depth will increase with cutting depth getting deeper or when the feed rate increases. However, wheel speed has no specific influence on subsurface damage depth. (authors)