We have developed Design Support Navigator. This support system is provided for machine elements design at the planning phase. That is, the system is usable to help basic design of machine elements using calculation tools and know-how database. We carried out a questionnaire survey about this system for some design persons in charges. This aim is promotion of education and design work for young engineering. As a result, it becomes clear that a popular design procedure and concrete design examples are demanded. We show an example that applied this tool to design screw fastening.

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Environmental and energy issues are causing major concerns as a result of the prospects of global warming. This report presents the authors' entries in the first event of the 'New Energy Contest' organized by Tamagawa University. The challenge in the contest was building a non-electric refrigerator. Students from universities and national colleges of technology were locked in a battle for various ideas to build a refrigerator. The authors designed and built two types of refrigerators: a refrigerator that uses a regenerative material and another that uses the combined effect of boiling at a reduced-pressure and an adsorptive material. Here we report on the design and fabrication aspects of the refrigerators and the measured final temperatures of the two refrigerators.

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It is opened a course in Basic Study Skill I〜IV as subjects of the for the first year experience at Kanazawa Institute of Technology. In this subject, the student understands specialty of faculty and learning method as the student of Kanazawa Institute of Technology and it is a subject for the purpose of improving a skill to act with a purpose positively. The student investigated the laboratory for the purpose of understanding own specialty in this subject. In this report, a result of the laboratory investigation of the student is introduced. And it is reported about a change of the consciousness for the specialty of the student.

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This paper describes a new virtual reality-based skill training and human resource development for undergraduate mechanical engineering students. The virtual reality-based skill training system is able to reproduce the environment of a casting technology. The most notable advantages of this system are that students can virtually experience the workflow prior to actually performing the practice at the worksite, one can learn about procedures beforehand. Our skill training allows the students to experience the perception of actually being in a particular environment.

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The subject of paper discusses the international education issue, based on the author's domestic and international experiences, utilizing TOEFL Test and Score Data Summaries of 2003 through 2008 and 1991-1993, among others.

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We aimed at analyzing the consciousness actual situation for technology of junior high schools student. We carried out investigation for 3192 junior high students in 14 junior high schools spreading over 10 prefectures with investigation by the consciousness standard for technology and SD method. About the consciousness for technology, a meaningful difference was recognized about" interest and eagerness to engage in technology", "interest and eagerness to engage in creative activities" in particular by boy and girl. About the image for technology by SD method, the tendency that we compared it with a girl, and a boy had a positive image was confirmed in some items of robot and machine.

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Recently stereo-visualization system is spreading on the domain of the educational technology. Stereo visualized contents are very effective on the education because students can recognize shapes and structures of the objects directly through the stereo vision. In this study, the easy and low cost stereo video camera system was developed and used in the practice of sketch a turbine engine. The learning effect of the stereo-visualization system was examined with a questionnaire. The result of the questionnaire showed that the practice of sketch through the stereo video camera system was very helpful to understand the structure of the turbine engine.

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There are four types in the lesson. These are enjoyable, not-enjoyable, understanding and not-understanding teachings. The author considers these teaching criticism. The author introduces enjoyable lessons (boomerang stunt planes, Bam-boomerangs, Boomerang paperc cups) in College of Technology. Students are interested in retuurnable matters with unexpected phenomena and mechanism of equations of motions.

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In this paper, the authors have developed a new type of horizontal seismic isolation table which has large effect of vibration isolation for ordinary earthquakes and suppresses the resonance of the isolation system due to long-period ground motions. The seismic isolation table is composed of a table board, X-Y rails, hardening type friction dampers and a baseboard. The effects of the isolation table were confirmed experimentally and numerically.

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When rubber rubs a plate-like object, friction-induced vibration is generated. And it often causes noise problems. This paper investigates the effects of some parameters on the stability using an analytical model in which the rubber is supported by elastic beam and Coulomb's friction is assumed. The results demonstrate that the unstable vibration occurs when the length of the beam is short. This corresponds qualitatively with the experimental results.

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The frictional behaviour is effective for dissipating seismic energy. Therefore, in recent years, the installation of a frictional isolator in industrial facilities has been investigated. In the present paper, the easy estimation of seismic respose for a 2-dof friction system based on a friction response spectrum and modal analysis method are proposed. Moreover, the applicable range of the proposed method is clarified by comparison with the result of non-linear time history analysis. The proposed method can obtain the seismic response of a 2-dof friction system immediately without non-linear time history analysis.

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For the passive isolation systems, a friction damper is often used because it is simple, inexpensive and reliable. However, the ordinary friction damper of constant friction force has performance limitations, because the isolation characteristic declines when the friction force is large, while resonance peak becomes large when the friction force is small. Furthermore, the displacement remains apart from the equilibrium position after the disturbance disappears. In order to overcome the above drawbacks of the ordinary friction damper, a new type of friction damper is proposed in our previous paper. This is achieved by use of an inclined lever, which contacts the cylindrical block by means of a rotational spring. When the cylindrical block moves, the angle of lever inclination varies, causing the normal and frictional forces at the contact surface to vary according to the displacement of the cylindrical block. However, sprag-slip vibration occurred in the experiments. This paper investigates the cause of the vibration and the design to prevent it.

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This paper describes the dynamic characteristics based on microtremor measurement data concerning a high-rise steel building. This microtremor measurement is continued periodically. The object building which was completed in October 1998 is 120m height and rectangular plan. The acceleration and velocity data in two horizontal directions and torsional direction are analyzed for natural frequencies and damping ratios on 1st mode to 4th mode. The changes along passages and the dispersions of those dynamic characteristics in microtremor are studied. And the relations between amplitude and damping ratios in free vibration waves by manpower excitation are discussed.

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In the relay, the contact trouble occurs because of a foreign body that exists on the electrodes. This paper presents the results of experimental and analytical studies of the motion of a charged particle under uniform electric field. The experimental apparatus consists of parallel plate electrodes vibrated with a shaker. The particle was charged in the rotating cylinders which are made of ABS or PTFE. The motion of the charged particle has been carefully investigated with a high speed camera. It was found that the motion of the charged particle depends on parameters such as electric field strength, amplitude and frequency.

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Casting motion is one of the methods for conveyance of an object. This paper investigates fundamental characteristics of the casting motion. The casting system consists of a rigid rod and a point-mass pendulum. The rigid rod can arbitrarily rotate around a fixed point by an actuator, and the pendulum is attached to the tip of the rod. The effects of some parameters of the motion of the rod on the landing condition of the mass are investigated by numerical analysis. In addition, the validity of the calculated results is verified using an experimental apparatus.

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In this study, the purpose is to formulate a three-dimensional motion of a wheel-set considering contact geometry by applying techniques of multibody dynamics and to discuss the errors of the constraint conditions. When the rail shape changes the constraint conditions of velocity or acceleration expression is not always satisfied. The errors of the constraint conditions are discussed by three-dimensional numerical simulation for wheel-set motion on track with irregularity.

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The purpose of this study is to formulate a motion of rigid bodies system with unilateral contact problems by applying techniques of multibody dynamics and to analyze the issue of rocking conditions of the rigid bodies with slide contact or collision. The system is a coupled vibration system composed of three rigid bodies elastically supported by excited foundation. The differential algebraic equation is solved by the augmented formulation with Lagrange multipliers, using generalized coordinates and non-generalized surface parameters that describe the contact point. The influences of rocking mode and slip on the rocking motion are discussed.

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The purpose of this study is to evaluate the performance for earthquake resistance of a server rack through vibration tests using floor response waves of some buildings. To reveal the fundamental dynamic characteristics of the server racks, it is made the vibration tests through the sinusoidal waves, and analyzed the influence of server rack sizes and additional mass. Earthquake response characteristics for severe excitation of the server racks are also investigated.

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The effect of music on driver's mental stress and driver's operation was researched with a simulator. Subjects were 3 healthy males. The heartbeat was measured for about 5 minutes without any stimulation, then for about three minutes simulated while listening to music with driving simulator, and finally, for a few times until observer was settling down. LF/HF and Reactive value, and Standard deviation of horizontal displacement, and Standard deviation of vehicle speed is used for the analysis (LF and HF denote the low frequency component and the high frequency component of the power spectra of heartbeat fluctuations, respectively). Under the speed of 60km/h music influence on driving is not so large. The influence is larger when vehicle speed becomes faster. It may be understood that subjects were similarly influenced by music when standard deviation of the fluctuation of vehicle speed is paid attention. As a result, a high relation between speed control and steering wheel control was read from the graph. It is revealed that the best music on driver's mental stress is usual tempo music.

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The multi-period repetitive control system is a type of servomechanism for periodic reference inputs. Even if a plant does not include time-delays, using multi-period repetitive controllers, transfer functions from the periodic reference input to the output and from the disturbance to the output of the multi-period repetitive control system generally have an infinite number of poles. To specify the input-output characteristic and the disturbance attenuation characteristic easily, Yamada and Takenaga proposed a design method for simple multi-period repetitive controllers, such that the controller works as a stabilizing multi-period repetitive controller and transfer functions from the periodic reference input to the output and from the disturbance to the output have a finite number of poles. However, their method cannot be applied to multiple-input/multiple-output plants. The purpose of this paper is to propose a design method for simple multi-period repetitive controllers for multiple-input/multiple-output plants.

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Multiple magnetic suspension suspends multiple floators with a single power amplifier. It is classified into parallel magnetic suspension and series magnetic suspension. In this paper, the feasibility of parallel magnetic suspension is studied experimentally. Parallel magnetic suspension systems are classified into series-connected and parallel connected according to coil connection. This paper focuses on the current-controlled multiple suspension system with parallel connected coils. Stable levitation with two floaters is achieved by using PD control.

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The object of this research is intended to build a wall of sound insulation using aluminum plates with active control of piezoelectric element. It was realized a space-saving and lightweight devices to use piezoelectric sensors and actuators. Building a smart structure by giving the appropriate control inputs to detect the disturbance itself, can reduce costs and auto maintenance personnel. This study is an aluminum plate placed on both sides of the microphone and speaker. The sound pressure level is measured in the control and without control. Control system using LQG control, state-space model obtained by system identification using chirp signals. Sinusoidal disturbance is generated from the speakers. To evaluate the performance, sound pressure level is measured by the aluminum plate with a microphone.

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Repetition design that improves the control performance of the closed-loop system has been proposed by repeating LQG control and closed-loop identification. In this paper, the theory of SIMO system is verified by experiment of the swing and stabilized control for the rotation type inverted pendulum.

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Air-damper can easily change the coefficient of viscosity and the spring constant by changing the air capacity of the air-damper. Therefore, to suppress the vibration of seismic waves, dynamic absorber with springs and air-damper is used by semi-active control. In this paper, a switching control, which changes the spring constant of air-damper based on frequency, is proposed and experimental results are shown.

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A new device for reduction system of seismic response is developed using friction bearing. This study investigates the influence that the change of center of gravity position due to the load affects the reduction of seismic response. In the best case, the seismic response at the top of computer rack decreases about 75% compared to the input wave. And, even in bad case, it was about 44% decrease. They indicate that this device do not depend on the load center of gravity position.

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A reduction system of seismic response for small structure that was installed inside buildings was developed using friction bearings. In this paper, effects of bearing combination on reduction were investigated by vibration test. The best combination of bearing is case 2 that was used two marble plates and two steel balls with rubber pad, and the maximum response amplitude decreases 80% compared to input wave. On the other hand, in case 1 that was used four steel balls, it amplified because of resonance between input wave and isolated plate.

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It is important for seismic disaster prevention not to turn over the small structure installed inside the building. A small device for reduction of seismic response of mechanical system is developed using friction bearing. To estimate the amplitude characteristics of seismic response of this devise, vibration test was done using artificial seismic waves. In acceleration, maximum amplitude values decrease about 20-40 %. Also amplitude values of root mean square are about 10-30 % decrease. In displacement, as maximum amplitude values decrease about 10-40% in same cases, but there are some amplified cases.

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"Safety plug switch" is used for controlling hazardous energy in order to protect the machine maintenance personnel working at any place where they could be injured by the unexpected release of hazardous energy. In view of the above, this paper proposes that the relation of "withdrawing and possessing the safety plug for hostage control," "unlocking the movable guard for opening it" and "accessing to the working space" should be made unate in terms of system by applying the "principle of safety confirmation" to the safety plug switch installation. To realize such unite system, this paper formulates these interrelations, presents them in the form of interlock structure and shows an example of configuration that can meet the required functions.

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The market of Human-Symbiotic-Robots that share active area with humans is growing. However, safety standards JIS and ISO for Human-Symbiotic-Robots are not provided yet. And, the risk assessment to them is difficult. In this paper, we propose a new technique of risk estimation of Human-Symbiotic-Robots that work like as humans. We measure movement histories of the human that is assumed to be Human-Symbiotic-Robot works in shared space. Then, we propose to estimate the risk based by the movement histories.

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New microactuators which are used for medical apparatus or inspection microrobots in the human body have been researched. The pneumatic pressure or water pressure have been utilized for microactuators. However, we have noticed a microactuator driven by gas-liquid phase-change phenomenon. When a liquid is vaporized, the volume of the gas produced is more than 100 times that of the liquid. Gas-liquid phase-change microactuators are thermal engines which utilize the large change in volume that occurs during a phase-change. We fabricated small scale artificial rubber muscle driven by gas-liquid phase-change.

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I suggest the function enables you to input from voluntary coordinate system to program modules. Constructed independently, past program modules are input from its peculiarity coordinate system. Then, by using this function, you can input from voluntary coordinate system to program module, and it simplifies the construction of various cooperation system consists of program module.

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A human interface using a robot face is proposed in this paper. The robot face was designed using simple mechanisms in order to achieve a low cost system. In this paper, the experiments on human facial expressions are conducted in order to investigate human emotion, and the simplified robot face was designed using the experimental results on human emotion.

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Precise force control is realized by a feedback control of pneumatic pressure using a servo valve, though a mechanical pressure control valve is used for rough force control. In the system design of this force controller, the dynamic characteristic of a servo valve is fast enough, and so has been neglected. Actually, however, the force control system depends greatly on the dynamic characteristic of a servo valve. The authors proposed a new system design method of the force controller for a rigid controlled object considering the dynamic characteristic of servo valve. In this study, this proposed method was extended to be applied to a compliant object which is often controlled by pneumatic pressure. It was concluded that the extended method is effective because good results of the force control are obtained.

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It is common to manipulate paper using manipulator. It is better to measure small thickness using manipulator automatically. The spherical tip on manipulator can put small thickness into bigger angle which is easy to measure. The measuring device is made of manipulator, force sensor and spherical tip. The accuracy of the measuring device should be satisfied with ±0.005mm, so the parameter which effect the accuracy should be checked. The experiment of measuring small thickness is made. The result shows that it is possible to measure thickness of accuracy of ±0.005mm with spherical tip on manipulator.

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Impact manipulation is an operation which a manipulator's hand impacts on an object and generates an impulsive force. In impact manipulation, apparent inertia of manipulator's hand affects an impulsive force and hand's velocity change. In this paper, we construct a manipulator's model which is considered manipulator's dynamics and estimate the impulsive force and hand's velocity change using this model. And we verify that manipulator's hand can get a larger velocity after impact than before impact in the tangential direction of impact surface by impact manipulation from the results of simulations and experiments.

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This research suggested a system that fixed the general dataglove on a manipulator. For using direct teaching method on manipulator and gets nessesary data for multifingers by dataglove, in teaching and playback process, this system holds high position accuracy of both fingers and hand position. The teaching process cost Moreover, this is a simple system with no high price components and easier for the operator. And the teaching process costs only a short time.

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Some manipulation tasks have a direction of motion and directions for which kinematic accuracy is required in the motion. We have proposed the index (KAIT: Kinematic Accuracy Index for Task-directions) that allows us to evaluate the kinematic accuracy of manipulators considering the task-directions. In this paper, first, the KAIT is explained briefly. Second, some postures of a 3-DOF planar manipulator are evaluated for a given task on the basis of the KAIT and Yoshikawa's manipulability measure. Finally, from the comparison of the evaluated results and experimental results which are obtained by using the manipulator, it is indicated that the KAIT are useful in determining the suitable posture of the manipulator for the given task.

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The generation of accurate maps and reliable path is necessary and indispensable for an autonomous mobile robot. It is preferable that is obtained simultaneously. In this paper, we propose an obstacle map and robot path generation method for an autonomous robot. This method aimes to generate the environmental map and path simultaneously and speedy by using Laser Range Finder that is more high speed than image processing for ranging, and Potential Field method that is able to get continuous path simply for path planning.The experimental result are shown.

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Abstract Abstract-This paper describes on the development of a tendon-driven biped robot that can absorb impact forces when it is walking, running, and so on. Furthermore nonlinear spring tension devices (NST) named mpNST are attached at the end of tendons.This device makes it possible to adjust the mechanical joint stiffness and guarantee the robustness for the impulsive reaction forces from the ground. Next, this paper describes on reinforcement learning of rules to correct the waist trajectory and tendon- tensile forces for stable walking by Improved Penalty Avoiding Rational Policy Making algorithm (PARP) based on Profit Sharing method (PS). Some simulation results are given.

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Penalty Avoiding Rational Policy Making algorithm (PARP) based on Profit Sharing method and was planed to learn a penalty avoiding policy. PARP is improved to save memories and to cope with uncertainties. The efficiency of the Improved Penalty Avoiding Rational Policy Making algorithm is influenced by threshold of the penalty basis function γ significantly. Up to now, it is necessary to set appropriate γ through a preliminary experiment. In this paper, we propose a technique for learning γ with the multi start method. The proposal technique is applied to a keepaway task that is a benchmark in a robotic soccer game, to confirm the effectiveness.

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High intake temperature is required in HCCI combustion fueled by natural gas owing to its large amount of CH_4, which auto ignition temperature is high. On the other hand, biomass gas, which consists of H_2, enables HCCI combustion to start in lower temperature. In this study, the influence of mixture of biomass gas and city gas refined by natural gas was investigated by experiment and calculation of chemical reactions. It was suggested that the decrease in ratio of 13A in mixing fuel caused auto ignition temperature to lower and required intake temperature to reduce.

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From the viewpoint of environment, HCCI (Homogeneous charge compression ignition) engine is very attractive. HCCI engine has both gasoline and diesel characteristics, therefore the engine can possible to perform the low emission and high efficiency. This study described the reduction of hazardous substance in exhaust gas of HCCI engine by simulation using CHEMKIN. From this study, H_2O addition can reduce maximum NO fraction and O_2 addition is effect measure to decrease in maximum CO fraction. The above explains maximum NO fraction and maximum CO fraction can be cut down at once. The best condition to decrease in maximum NO fraction and maximum CO fraction is H_2O+10.9% and O_2+5% from reactant species in this study conditions.

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Homogeneous Charge Compression Ignition (HCCI) combustion has attracted considerable interest in recent years as a new combustion concept for internal combustion engines. The HCCI combustion process has four issues to be resolved: ignition timing control, slower combustion reaction rate (maximum heat release rate), difficulty expanding stable operation to the high load region and avoidance of knocking. Supercharging is an effective means of increasing the load of an HCCI engine, but its effect on combustion is still not clearly understood. This study examined the influence of the intake air pressure on the low-and high-temperature reactions of an HCCI engine operating on DME and methane.

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