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During neural activity in the brain, humans transmit and process information and decide upon actions or responses. When neural activity occurs, blood flow and blood quantity increase in the tissue near the active neurons, and the ratio of oxygenated to deoxygenated hemoglobin in the blood changes. In this paper, we used near-infrared spectroscopy (NIRS) to determine the state of hemoglobin oxygenation at the cerebral surface and on that basis performed real-time color mapping of brain activity (the brain activation response) in the target regions. In this paper, we describe measurements of brain activation using NIRS so as to clarify any differences between conscious and unconscious movement. Bio-locomotion is divided into voluntary movements, which are made voluntarily and consciously, and passive movements, which are made passively and unconsciously. Accordingly, in this paper we investigate the brain activation associated with these two types of movements. The subject successively moves his/her lower legs through knee bends. We measure the brain activities while the subject, who is sitting on a chair moves back and forth. In addition, we carry out an experiment on the effects of the existence or nonexistence of movement caused by vibration on brain activities to consider the results.

Research on brain-machine-interfaces (BMIs) is widespread and rapidly growing in concert with the rapid advances of recent years in brain science and engineering, and systems technologies for interactions between human and machine are of major interest. It is very important for development of BMIs to analysis brain activities. In this paper, we present measurement of brain activation response for weight shifting and center of gravity movement trials using near-infrared spectroscopy (NIRS). We measured their brain activations by NIRS. To evaluate effects of skin blood flow, we used probes with two distinct distances (15mm and 30mm) for NIRS and simultaneously measured skin blood flow. We also measured the position of the center of gravity using the ground reaction meter. The results showed that oxy-Hb changes were influenced by direction of movement. We also found that NIRS signals generally reflected skin blood flow.

An environment where Japanese industry has been paid with respect is changing tremendously due to the globalization of economics, where other Asian countries are undergoing economical and technical development as well as advancing in information technology. With acceleration of manufacturing bases relocating abroad, industrial hollowing out is happening; hence effort to transfer the technology and the design knowledge of machine design in a company is becoming an important subject. For example, in the design of custom casting products, a designer who is lacking in casting knowledge may not be able to produce a good design. In order to obtain a good design and manufacturing, it is necessary to equip the designer and manufacturer with a support system related to casting process or so called, knowledge transfer and creation system. This paper proposes a new educational support system for manufacturing technology; where machine design, which requires added values such as advanced technology, high quality, and short delivery time, is taken as an example and both its explicit and tacit knowledge are cooperated by using synchronized multimedia and immersive virtual environment.

In recent years, decreasing skilled workers have become a big problem in our country. Therefore a method or system is necessary in which unskilled workers can obtain high level skills such as crane operation on creating a mold efficiently. Since OJT (On-the-Job Training) is one of the main methods of knowledge transfer and job training, however it is limited due to decreasing young workers and aging of skilled workers. In this paper, the VR-based training system for crane operation is shown. We conduct the experiment that trialists use the system. As a result, the effectiveness of the VR-based training system for a crane operation is considered.

Analytical results are presented for vibration of a wide timing belt under a moving load. The equation of motion is derived from Hamilton's principle, and approximate solutions to the basic equation are obtained using the Galerkin method. The steady-state responses are calculated using the harmonic balance method. Analytical results are presented which show the contributions of moving load position and moving load value to response curves. The response amplitude that varies with the width of timing belt. In the case of variable velocity, the response value shows very complicated behavior with pulley rotation. The response curves of vibration are greatly influenced by the moving load and the velocity.

It is difficult to drive an actuator using muscular voltage measured by the conventional method, which is based on medical treatment and is not intended to elucidate the movement of an arm. In this paper, we propose a suitable measuring method to elucidate the movement by changing the position of an electrode. We also propose two evaluation values calculated from measured voltage to represent the movement of an arm. Using a fuzzy method based on these values, we can represent the movement of an arm fairly well. We applied this fuzzy method to driving an arm-type actuator, which can reproduce the movement of an arm.

When we obtain analytical results for a mechanical system by numerical analysis, we may consider many kinds of physical influence, including electricity, mechanical vibration, heat, and flow. However, it is difficult to deal with each system simultaneously. In this study, with the aim of the convenient analysis of a thermo-fluid system, analysis using linear graph theory is derived, and the transient response analysis for a piping system is carried out. Furthermore, in order to examine the validity of this analysis method, the finite-element method is carried out and its results compared with the simulation results. Through these studies, it is concluded that the convenient method is useful in analyzing mechanical systems including the thermo-fluid system.

We have developed a small jumping machine. For such machines, it is difficult to control the direction and velocity of motion by using conventional control devices, since there is not sufficient space to install them. Therefore we must develop another suitable control method. In this report, we investigate the following and movement control method of a small jumping target and elucidate its performance by analyzing graphical data extracted using a CCD camera. We propose a method of creating a virtual eye on the computer display, with which to follow a target. Moreover, we propose a controling method of jumping direction and velocity.

The macrofunction in computer-aided manufacturing (CAM) is executed besed on a macrocode which is transformed by a series of operations input by the user. By the use of this function and a frame of a macrocode (macrotemplate) on mechanical parts, we have developed a function for transforming macrocode from data of a CAD drawing to a CAM drawing. However, it is very difficult to build the macrotemplate in the knowledge base, because to do that it must understand CAM operations very well, and the macrotemplate should be tailored to the object. In this paper, we describe a method for generating the macrotemplate automatically, and demonstrate that we have been able to achieve NC machining easily.

Recently, the importance of system design in the field of mechanical engineering has been increasingly recognized. However suitable and useful methods for machine design are not yet established. An analytical method of the dynamic characteristics in the mechanical system, a method utilizing linear graph theory, is proposed. In this paper, for practical use of this analytical method, a program is developed which can analyze the dynamic characteristics automatically. As an example, in the mechanical vibration system, with the arrangement of the elements on the computer display, the system graph and the equations of motion are automatically produced by means of a cut-set matrix, and the dynamic characteristics of the system are derived by means of a computer algebraic method.

With application of an expert system for practical purposes, knowledge representation has become increasingly complicated, and current Artificial Intelligence (AI) tools cannot represent the knowledge of experts very well. Therefore, systems built by these AI tools are not adaptable in cases of actual application. Hence, we have investigated optimal development of an appropriate knowledge representation in consideration of actual applications. As a result, by modeling "function" and "structure" on traditional AI tools based on the concept of the object model, we have developed a system which creates a source code (language) automatically. This paper describes knowledge representation for building of AI tools and the method for creating a source code automatically.

In the previous paper, we reported friction characteristics of K2Ti4O9 as a base agent of disk-type brake pad. The use of K2Ti4O9 seems to be effective in increasing the friction coefficient, but it causes abrasion and a great deal of wear. In this study, the authors investigated the characteristics of a new base agent using processed K2Ti4O9 in HCl, then in Cu(OH)2 so that K2Ti4O9 was transformed into CuTi4O9. In friction materials using CuTi4O9 as abase agent of disk-type brake pad, thermal decomposition of the base agent and combination with Phenol-resin occurs at almost the same temperature. Because thermal conductivity of CuTi4O9 is high, phenol-resin decomposition is difficult. Consequentry, CuTi4O9 will be effective decreasing the amount of wear.

With the increasing application of large-scale and complicated systems in practical use, there is a need to develop systems on engineering work stations (EWS), in consideration of memory and speed of processing. However, it is very difficult to develop an application program with a graphical user interface (GUI) on an EWS. The authors have built a model of GUI based on the concept of object-model, and developed a function to create a source code of GUI by using this model. In this paper, knowledge representation of the model, the method for creating a source code of GUI by means of the model, and the method for controlling communication between the application and GUI are described.

Structures which can be modified to make fine adjustments to arbitrary structural surfaces have been investigated in the construction of space structures. Considering the geometrical configuration of these structures, the. same concept might be applied to structures such as those which are used in collecting sunlight. In this paper, we describe a designing method by which to build to build structures that can be extended and adapted to a parabolic structural surface.

Recently, the importance of system design in the field of mechanical engineering has been increasingly recognized. But suitable and useful methods for machine design are not yet established. An analytical method for the dynamic characteristics in the mechanical system, a method using linear graph theory, is proposed. In this paper, for the purpose of the practical use of this analytical method, a program which can analyze the dynamic characteristic automatically is developed. As an example, in the motion transmitting mechanism arranging the elements on the display of the computer, the system graph and the tableau equation are automatically produced, and the dynamic characteristics of the system are derived.

Investment in miclo-moving devices has been carried out. In many cases, their driving principle is based on a small amplitude of vibration. But, using this principle, it is difficult to move smoothly if there are holes or differences in level. In this paper, I have tried to make a device which can jump over obstacles and move smoothly on a rough surface, and then have examined its characteristic obstacles condition. This device has some functions for moving adjusted to the change of, for example, jumping in all directions moving quickly and recovering when it falls down.

Recently, the fine positioning system has been used in the mechanical industry, and has required the improvement of positioning accuracy, reduction of positioning time, increase of carrying capacity and so on. However, the existing control method for the positioning stage may cause delay of phase response or residual vibration when disturbance or overweight acts on the system or stage drives at high speed. In order to obtain the optimum control inputs, it is necessary to grasp the dynamic behaviour of the system precisely. First, this paper deals with the transient response of the positioning stage using the linear graph theory reported in the previous papers. The simulated results of transient response of the positioning stage are compared with the experimental ones, and they are found to be in good agreement. Next, a procedure which can reduce the settling time of positioning is proposed by utilizing this method. As a result, this procedure was able to reduce the settling time by 55%, as compared with only proportional control.

At the present time, the machines with high accuracy and performance tend to be designed by CAE methods. But suitable and useful CAE methods are not established for all machine parts and elements. Thus, we must derive easy and useful methods for each machine part. This report deals with a new method using linear graph theory as one CAE method and analyzes the results of dynamic behaviour concerning power transmission mechanism. By this method, addition and deletion of machine elements are made flexibly, and performances of the system are analyzed rapidly. So this method is effective for extensive machine design.

各種自動機械に用いられている位置決め装置の構成要素であるカムなどは,機械の高精度高性能化に伴って,多種多様な形状のものが使用されるようになってきている.しかしこのような機械要素の応力分布および変形に関する研究はほとんどなされていない.そこで,本報では,複素応力関数を利用して理論解析を行い,種々の形状のカムについて応力分布および変形を求めた.