The experiment and linear analysis of impact pressure by sloshing due to liquid swaying was conduct. The analyzing values of the wave amplitude on the basis of the theory of velocity potential were the almost same order as the values of experimental wave amplitude. The analyzing values of the impact pressure at the upper wall of the container on the basis of the theory of velocity potential were also the almost same order as the values of experimental impact pressure. Therefore, the wave movement and pressure variation due to the sloshing with the container swaying can be predicted by using the simple method or the linear analysis based on the velocity potential theory.

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Magneto-rheological materials are a class of smart materials whose rheological or viscoelastic properties can be varied by applying external magnetic field. MR elastomers (MRE) are the solid analogues of MRF and are expected to overcome the disadvantages of the fluid such as the particle deposition and the sealing problems. When such MRE are exposed to external magnetic field, their apparent elastic modulus is changed depending on the magnitude of the field. In this paper, the stiffness controllable elastomer composites known as MRE are first fabricated and their field-dependent static and dynamic properties are tested. The MRE is then applied to the vibration isolating mounts along with variable stiffness control scheme. Experimental investigations show that the vibration of the one-degree of freedom structure that is exposed to base excitation can be effectively reduced according to the semi-active on/off switching control algorithms.

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For a measurement of very small damping, we propose a method of identifying damping by free vibration. The free vibration response is measured by using sound with the vibration. Two methods, method of using the adaptive notch filter and method by curve fit through synthesizing multiple sine wave, are tried. As a result, valid values of damping factor can be obtained from the method of using adaptive notch filter.

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In recent years, destructive earthquake disasters have happened in the world. It is important to reduce the seismic response of houses in order to prevent from collapse of houses. Some control methods for seismic response of houses are developed. The oil dampers using the flow resistance of the silicon oil have been developed. In this paper, a Magnet Oil Damper (MOD) in which permanent magnets are added to the oil damper is proposed in order to improve the performance of the oil damper. The effect of MOD is examined experimentally. The damping ratio is large when MOD is used. The effectiveness of MOD is examined by simulation method. From simulation method using the analytical model, it is found that the response decreases when MOD is used.

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In this study, dependence of damping force of the particles damper on setting angle is investigated experimentally. The damping force is measured by using the load cell while the displacement is measured by the laser displacement sensor. It is shown that damping properties strongly depends on the setting angle of the damper due to the gravity.

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To solve problems such as CO_2 emission and sudden traffic demands in the transportation field, automatic platooning is expected to be an efficient method. However it is required to validate automatic platooning for the reliability and the driving safety before driving on a highway. To confirm the validity of the automatic platooning, a simulation system is constructed for the automatic platooning using the Simulink model of control algorism, controller, KAKUMO which is micro traffic simulator and a universal driving simulator, and conducted the simulation for the automatic platooning of two trucks on a straight highway. Through the simulations, the reliability of the simulation system was validated. Moreover, it becomes possible to carry out a simulation test for an examination at the situation of emergency during the automatic platooning.

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A huge, natural energy is unused in oceans of the world, and development of power generation utilizing ocean energy is important though there are various advantages and faults compared with solar generation and wind power generation. In this study, we have paid attention to an oscillating water column type wave energy converter in various approaches. Then, we presents on a study and development of a physical model to be able to explain using a hypothesis of changing open and close systems that if the size of multiple jets is smaller in some degree amount of power generation increases as number of jets in a ceil of the converter increases.

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We are proposing a liquid rate gyro named "ECF micro rate gyro". Although the sensing principle is based on that of a conventional gas rate gyro, the liquid micro rate gyro works by an electro-conjugate fluid (ECF) instead of a gas. The electro-conjugate fluid is a dielectric fluid that works as a functional fluid, generating a powerful jet flow (ECF jet) when subjected to a high DC voltage. In our concept model, an ECF micro rate gyro was made by machines and handwork. In this study, we propose a MEMS fabrication process of ECF jet generator, flow channel and sensing hot film, which are parts of the ECF micro rate gyro. By using MEMS technology, we can downsize and integrate an ECF micro rate gyro. Then we perform functional test of the fabricated prototype and confirmed a function as a rate gyro. Further study is necessary to have an improved performance of sensing hot film and the micro rate gyro.

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A smart tap which can monitor power consumption for electrical appliances has attracted attention in Building and Energy Management Systems and Home Energy Management Systems (BEMS, HEMS). However, most smart taps cannot control electricity consumption of appliances from remote. In this paper, we have developed a new smart tap, called Intelligent Power Tap, which can collect power consumption data and control electricity consumption of electrical appliances via wireless network. Then, we have designed a Wi-Fi sensor module board for wireless network communications. Moreover, the effectiveness of the developed intelligent tap is demonstrated by an experiment on remote fan control.

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The demand of consumers for quality of the fruit rises, and the producer produces things having high quality, and a study to evaluate in nondestructive definitely is pushed forward. Here, we measure the spectral reflectance of the mandarin orange epidermis color as a method to perform the quality evaluation of the mandarin orange and calculate colorimetric value. We analyzed relations with brix and colorimetric value and studied a method to estimate the maturational degree before the crop nondestructively. As a result, 0.81 and high correlation were provided a mandarin orange and a coefficient of correlation of epidermis color b* that they divided into 12% from brix 6%. In this way, we confirmed the maturity of the mandarin orange and the change of the color of the immaturity with the numerical value of the color system when the distinction of the brix was possible.

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Series magnetic suspension is applied to force measurement. In a double series magnetic suspension system with PID control, the upper floator displaces when force acts on the lower floator. Therefore, the force can be estimated for the displacement of the upper floator. When the parameters are set appropriately, small force leads to large displacement so that the proposed measurement method can be suitable for noncontact measurement of microforce. An apparatus was fabricated to study the effectiveness of the proposed method experimentally.

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This paper presents an improved evaluation of the axial elastic force in three-dimensional Bernoulli-Euler beam element based on the absolute nodal coordinate formulation. An accurate measure of mean axial strain for evaluating the axial elastic forces characterizes the presented formulation. The presented formulation evaluates the mean axial strain accurately by measuring the length of deformed beam element along its neutral axis instead of the straight-line distance between two element nodes. A comparison of the conventional formulations of the axial elastic force and the presented formulation is performed in numerical example which contains large bending deformation of flexible beam. As a result, it is verified that the presented formulation can express large deformation more accurately with smaller number of elements than the conventional formulation. Moreover, it is also verified that the presented formulation can avoid excessive increase in computing time to simulate the dynamic behavior of flexible beam.

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This paper proposes a novel absolute displacement sensor aimed at detecting long period and large amplitude. However, since the measuring range of the sensor is higher than the natural frequency of itself, it is difficult to measure the frequency with the conventional displacement sensor. In order to provide an absolute displacement detection which is capable of lowering the natural frequency and enlarging the detectable amplitude without causing a structural defect, the relative signals of acceleration and velocity between a detected object and the internal mass of the sensor are feedback into the sensor. In addition, phase lag compensator is inserted to adjust phase angles. Theoretically, this sensor is able to detect a lower frequency range from 10Hz to 0.2Hz and the large amplitude with 100 times to the movable range of the sensor. It has been demonstrated that the developed sensor has 0.2Hz of the natural frequency and the measurement displacement amplitude has been expanded to 25 times at present.

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Gear is a handy power transmission machine element, and is widely used in industrial machineries. However, it yields vibration and noise with the rotation. Various researches (1) (3) have been made on this problem so far. In the past research, it is said that the vibration of the meshing frequency was caused by the change of equivalent stiffness of meshing teeth. However, it is observed experimentally to receive the influence of the lubrication. Moreover, when considering the lateral-torsion coupled vibration, the vibration of power transmitting direction and teeth slide direction are said to be independent while slight interaction is observed experimentally. In this study, we experimentally confirm the phenomenon, and investigate the cause.

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Now, in the 21st century, the safety function for automobiles is dramatically improved. In 1970, the number of fatalities by the traffic accident decreased to 4 thousands since 1952. However, the number of fatalities is afraid to turn up to increase in the future aged society because half of all fatalities are accounted for by elderly people. So, it is absolutely necessary to improve the safety function furthermore. In this study, a front vehicle collision accounting for 70 percents of fatal accidents is treated, and an analytical model for human response due to front collision is established. Furthermore, an impact force reduction is studied by optimizing parameters of the vehicle with using genetic algorithm.

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There have been a number of issues concerning the sliding characteristics of oil-impregnated sintered bearings caused at the temperature below zero. However, the relationship between bearing design parameters and tribological characteristics below zero has not been clarified yet. In this study, we experimentally investigated the coefficient of friction and separation degree between the oil-impregnated sintered bearing and the journal operating at below-freezing temperature. As a result, we found that apparent reduction in oil content within porous matrix due to the volume contraction of lubricant oil with decreasing temperature led to boundary or mixed lubrication condition, yielding a high and unstable coefficient of friction.

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This paper deals with topographical characterization of textured 3-D (areal) tribosurfaces focusing on summit parameters. Contact summits are extracted based on the elastic contact analysis using the influence coefficient method. Parameters such as the contact summit density, mean contact summit area etc. are obtained. The presented method is applied for the textured pulley surfaces of a belt-CVT. Textured surface are prepared by using the shot peening, lapping, turning and grinding. Results show that the contact summit density has a good correlation with the coefficient of friction. Specifically, the higher coefficient of friction is obtained when the contact summit density is higher. Also, it is found that the mean contact summit area is small when the coefficient of friction is large. These results demonstrate the importance of the summit parameters to the tribosurface texturing.

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PTFE (polytetrafluoroethylene) has various unique properties such as low friction, non-adhesion, and insulation. CNF (Carbon nanofiber) is one of the promising materials to reduce the electrical resistivity of composite materials by dispersing very small amount. In this study, in order to improve the electrical resistivity and the abrasion resistance of PTFE films, we fabricated the PTFE/CNF composite films using an ultrasonic homogenizer. We quantitated the degree of dispersion of CNFs in the composite films by using fractal analysis and the effect by the difference of dispersion conditions was compared. Next, two types of friction test were carried out by using an adhesion friction tester and a ball-on-disk friction tester, and studied the effects of CNF addition on the tribological properties of PTFE/CNF composite films. As a result, we achieved the sufficient dispersion of CNFs by homogenizing for three minutes by ultrasonic. The coefficient of kinetic friction of PTFE films was not sensitive to the effect of counter materials, applied load and CNF addition. However, the specific wear rate of PTFE films decreased with CNF addition.

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In this report influence of material parameters on dynamic friction characteristics of paper-based wet friction material was investigated experimentally. Dynamic friction characteristics were represented in the form of complex friction coefficient which was defined as frequency response function of friction force with respect to normal force. As a result of experiments the tendency that amplitude of complex friction coefficient and its phase angle decreased with the increase of exciting frequency became more significant when the dimension of square surface was larger or the compressive modulus was lower. This was considered because the flow resistance of the internal lubricant inside the paper-based friction material became larger in those conditions and because the simultaneous pressure rise made the solid contact relaxed and delayed.

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The purpose of this study is to investigate the 3-D flow of the lubricants around the mesh-ending region of a rotating helical gear pair. One of the roles of the lubricants is cooling tooth surfaces, so it's desirable that the lubricants should be delivered adequately to the tooth surfaces just after the meshing. It's supposed that the lubricants flows might be affected by the air-flow around the mesh region. An effective lubrication should be considered with the flow. In this report, an experimental apparatus is introduced, and the summarized 3-D behaviors of the flow around the mesh-ending region of the rotating gear pair are shown. In these experiments, an acrylic helical gear pair is immersed into the water, and driven. Tracer particles are injected above the meshing like lubricants but against meshing direction and the tracings are visualized. The motions of the particles are captured by a high-speed camera. The camera is located to be able to look into the space between the teeth. Optical astigmatism is introduced intentionally into the system for the observation with the high-speed camera. With this optical system, distorted elliptic images of the particles are observed when the particles are out of focus.

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This paper deals with displacement control of water hydrostatic bearing using a water proportional valve. Generally, the hydrostatic bearing supports the loads by varying the recess pressure according to the displacement of the supported object. The recess pressure varies with pressure drop through the bearing restrictor that has particular pressure-flow characteristics. Therefore, when the load acts on the hydrostatic bearing, eccentricity or displacement occurs, then the accuracy of positioning becomes worse. To solve this problem, displacement control of hydrostatic bearing with variable restrictor mechanism is required. The overlap of the spool valve of originally designed water proportional valve is used as the variable restrictor. The experiment results of the displacement control of water hydrostatic bearing are shown. Pressure difference between the top and bottom recesses increases by control of the displacement of the spool valve, consequently, the load capacity is increased. Maintaining the infinite stiffness with the experimental rig was achieved in the load range up to about 400 N.

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This paper describes a cam-drive type proportional valve for water hydraulics and its dynamic characteristics. A spool in a conventional proportional valve is balanced by forces generated by the proportional solenoid and the spring. To cope with large force acting on the spool, it requires a strong solenoid and heavy core. Thus fast response of the valve is hardly realized. In the developed valve, the spool is driven by positive cam mechanism, in which a heart-like cam is placed between two cam-followers and the cam is driven by a stepping motor. The spool displacement is feed backed by microcomputer-based system and the stepping motor is proportionally controlled. The static characteristics are measured without the feedback control system. Non-linearity of the spool displacement against the rotational angle of the cam was below 0.2% and the hysteresis was hardly observed even though no feedback control loop was added. As for measurement of dynamic characteristics, the step and ramp responses are measured using the constructed controller with microcomputer.

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The present study describes breaking process of glass bar having radial cracks induced by Vickers indentation technique. Vickers impressions were introduced on the center of the glass bar at various indent loads and specific interval perpendicular to the longitudinal direction. The breaking process was carried out at 3-point bending technique using an electro mechanical testing apparatus at a constant cross head speed in air. The fracture surface morphology was evaluated with an optical micro scope and stylus profile meter. Results showed that the surface morphology including roughness and straightness generated after the breaking process was different depending on the indenting condition a flat surface with straightness was obtained at the indenting condition of 5 N of applied load and at a 70 of the interval.

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CVT rubber belt is a rubber composite material off a rubber, helical cord and a facing fabric, and is underwent a complex loading, because the CVT performs as both of a variable speed device and a power transmission. Therefore, the fatigue failure mechanism is complex, and has not sufficiently been understood. There are three major crack initiation modes for the CVT rubber belts, namely the adhesive rubber crack, the bottom land crack and the tension rubber crack. Moreover, wear is often observed as the fatigue failure mode for the CVT rubber belt. In this study, CVT rubber belt changed the shape, to examine the effect of life due to changes in shape by doing the driving test.

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According to the definition of "System" in various standards and handbooks, a system does not necessarily have hardware-software components. This means that a social system without hardware-software elements is a kind of system. However, systems engineering techniques are not directly applied to define a solution of a non-technical social system's problems. There are several architecture frameworks which identify the useful viewpoints. But the architecture framework can be applied only to a specialized domain. In this paper, we propose a standard approach to find out multiple viewpoints to describe architecture, because the viewpoints are one of the most important aspects of architectural design activities. This approach is "Enabler/Constraint" Framework. At design phase, a system has to achieve objects under several constraints. The enabler framework visualizes the required lower layer system. The constraint framework visualizes the required rule system. The combination of enabler and constraints realized the governed system. As the example of the application of enabler/constraint framework will shown.

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This paper describes the proposed circular framed structure and the developed method for impact response evaluation of structure. We propose a new concept of body structure, which is composed of the standardized circular unit members and is bundled together in parallel regions. To evaluate this circular framed strucure in the conceptual design stage, impact response evaluation method is developed. The main features of this method are three items shown below. (1) The dynamic FEA program of three dimensions using beamelerrent (nonlinear spring is included). (2) Joint stiffness is expressed by rotational stiffness of the end of a beam. (3) Newmark 13 method is used for time integration. By updating the geometry and calculated results, geometrical nonlinearity is also taken into consideration. The effectiveness of this proposed circular framed body strucure and the validity of the evaluation method were shown by some example calculations.

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The purpose of this paper is to estimate thermal deformation of machine tool model by using transfer function with time delay. The machine tool model is a symmetric gate type that combines two L character type materials. We assume that a left L character type material is the tool side and a right material is the construction side. It thinks between those to be a cutting area. The prediction method of thermal deformation based on frequency domain is constructed from transfer function between specified surface temperatures and the relative displacement in cutting area. The relative displacement in cutting area is predicted using two specified surface temperatures near heat source in machine tool model. As a result, the method can be predicted with enough certainty at what rate the temperature changes the most rapidly on machine's startup transient behavior. The method proposed in this paper is remarkably effective to estimate thermal deformation and confirm that the error between experimental and estimated values will be remarkably reduced.

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Several interdisciplinary research projects of renewable energy-driven residential environment have been actively conducted at College of Engineering, Nihon University However, most of renewable energy is strongly affected by atmospheric conditions so that predicting the generated power is relatively difficult in practical. This means that the renewable energy should be used under adequate energy management especially to maintain sustainable environments. In this paper, a modeling platform which emulates the dynamics of natural and residential environment in real-time has been presented. First, the architecture of the proposed emulator has been explained. Then, an experimental prototype employing a reduced-size model house with adequate energy supply, storage and consumption has been developed. Finally, the experimental result shows that environmental information such as energy data and atmospheric sensing data can be observed in real-time. The experiment also implies that some accelerated tests can be performed by the emulator under certain environment conditions.

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Amount of power generated by renewable energy at a particular site depends on its atmosphere as well as time of day. In this paper, a potential energy storage system which is effective for renewable energy leveling in home application has been presented. The system consists of weight lifting mechanisms as well as power generators driven by excess potential energy. Two types of experimental apparatus have been considered for feasibility study. Combined unit type storage for both lifting and generating functions is relatively compact but has difficulties in power design optimization. For split function type storage, a rotor-generator mechanism with multi-dynamo arrangement has been developed. The experimental result shows that the power conversion rate of the split type generator increase almost 5 times compared to the combined type storage case.

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Focusing on daily life of elder people or physically challenged, we propose a life support system considering the intuitive control of users. To control this system, users just use an interface of the system intuitively. Targeted users are often not familiar with mechanical / electrical systems. Thus, ordinary life support systems, which require users or operators complicated control formalities, are not suitable for our purpose. For overcoming this, we propose a way to control the system easily and intuitively. In this paper, an application for the locomotion of a physical agent, which is consisted of mobile robot and some end-effectors for the life support, is proposed. In addition to this, the application was implemented on handheld devices with Android OS and validity of the proposed system was shown by experiments.

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As for the true result of the technical tradition in the manufacturing industry, a person of technical reception creates result of the work actively, and ability it is to improve achievements, and to be required here is the ability that integrated two ability of competency which should say with ability and the sufficient condition. By the unification of such ability, it is important that I think about the aspect of the achievement degree rating system of the tradition technology, and the aspect here is various point of view such as an evaluation object, a method, a model when I carry out technique tradition. In this study, I feature the theme of an aspect and the making of such an evaluation standard the design and I examine the feasibility of these designs, reality, inevitability and I study the proof of the design in the next study and examine the consistency with the design of this study and a research theme.

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This research propose a method of production scheduling using autonomous distributed systems which includes not only machine but also Human and AGV's schedule. Moreover this method realizes real time scheduling and parallel scheduling. Therefore, a new structure of production scheduling is proposed, which can realize to change a type of production scheduler to correspond with a type of production system. Especially this paper focuses on the effect of bottle neck process. Some sample experiment is performed and some problem is discussed.

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In this paper, we discuss a technique for the dynamic assembly scheduling in an autonomous production system using product agents, parts agents and assembly machine agents. In this agent based assembly system, parts agents lead promotion of assembly process. Product agents generate the process plan that contains the assembly sequence to complete the product, and parts agents select machine by using this assembly process plan. Each parts agent requests order change to the other parts agent that is immediately inferior in the production's deadline, the assembly schedule is generated dynamically. However, there are some scopes for improvement in agent's behavior. The technique for reduction in a total time of job termination is shown.

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Disaster drills are important for minimizing the damage caused by earthquakes, floods, and fires. Therefore, mass-evacuation drills are considered to be an important obligation of schools and workplaces that employ several individuals. Moreover, for the validation of drill effectiveness as well as disaster prevention, the significance of mass-evacuation simulation has increased. In the present paper, a three-dimensional mass-evacuation simulation is first explained. The developed multi-agent-based simulation with a detailed three-dimensional building infrastructure uses a kinematic digital human model with precise human joints. Simulation of a mass-evacuation drill by high-school students agrees well with the results of actual drills. In addition, considering the transportation of badly injured persons during disasters, digital human motion sets of patients and transporters have been developed for critical evacuation simulation. Several examples have revealed the possibility of applying the extended simulation to evacuation from houses and hospitals.

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Focusing on the daily life of a student in a school, we propose a novel method to utilize the Life-Log. In many schools, for improving quality of the education, increasing the time spent for studying, encouraging research activities, and so on, they have revised a curriculum in the education, introduced many novel informational systems and services for the attendance, the education and the encouragement of activities. These systems and services are useful. However, even if logging information of the attendance and so on is done automatically, faculties process information and guide/coach students by themselves. Our proposed system processes life-log information of students, and gives students some small suggestions for changing their way to do or their mind. In this paper, we proposed a system-architecture of the proposed system based on the PDCA-cycle, which has been developed on the industry, the manufacturing process and the system development. Implementing it as a web-service and using it on the laboratory practically showed the validity of the proposed system.

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As for the mechanism of the movement in omni-directions, the smooth moves are more possible than conventional mechanisms, and the applications to electric vehicles and a personal mobility are expected. However, more complex operations are needed as for omni-direction mover. Therefore, the development of an easy-to-use human-machine-interface (HMI) for the user is needed. In this study, we investigate the technique for evaluating the usability of the HMI by using the movement in omni-directions. We also evaluate the usability using evaluation parameters such as the time of task completion and the time of protrude the line.

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This paper presents a mechanism and a control method of a personal motor vehicle (PMV). The PMV has been developed under three design concepts. (1) It must be able to be used as a baggage and passenger conveyance system. (2) It must be lightweight and compact size. (3) It must be easily controlled by a user. The PMV consists of two wheels, an EC servo-motor, a differential gear and a base. Its total weight is 13 [kg], and the height of its base is 0.2 [m]. Its maximum payload is 100[kg]. A gyro sensor is installed to detect the inclination angle of the base in the pitch direction. A simple motion control is employed for the PMV, which is based on the inclination angle. Several passenger and luggage conveyance experiments are conducted on a flat and rough terrain, and the effectiveness of its mechanism and control method is confirmed.

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This paper describes a method that calculates the compensatory trajectory of the waist based on preview control, and the mechanism of KBR-1R (Kanagawa Biped Robot 1-Refind). KBR-1R consists of 15 DOF such as 2 DOF in each ankle, 1 DOF in each knee, 3 DOF in each hip and 3 DOF in the waist. It is designed with a large movable range like a human. The waist motion calculated by the method cancels moments generated by the motion of the legs. In order to confirm the method, walking simulation is conducted using MATLAB/Simulink and Adams. Also, through walking experiments, the effectiveness of the control system and the mechanism confirmed.

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This paper describes the mechanism and the control system of a seahorse robot that is able to express happiness, sadness and anger. MP motion sensors (Pyroelectric Motion Detection Sensor), force sensors and light sensors are employed for the emotion expression. The seahorse robot consists of a base, a body and a head. It has 4 DOFs (2 DOFs in the head and 2 DOFs in the body) and its weight is 800 [g]. Emotion expression experiments were conducted to confirm the mechanism and the control system of the robot and were evaluated by ten subjects. After they watched the body color and motion, they select one of five emotions. The effectiveness of the mechanism and the control of the robot are verified through emotion experiments.

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This paper describes a robot capable of inspecting a pipe. The robot consists of a fore leg system, a rear leg system and a body. The fore and rear leg systems are constructed by using three worm gear systems that are arranged at an angle of 120 degrees with respect to each other to operate inside pipes of different diameters. Also, the body is designed with two joints so as to change the direction in pipe junctions. Several experiments are conducted in pipes of different diameters, and the effectiveness of the mechanism of the robot is confirmed.

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This paper describes a pipe inspection robot with multiple joints. The robot is composed of units and connecting links. For the robot to move in a horizontal pipe, three or more units are connected. On the other hand, four or more units are needed in a divergence pipe. Also, it is able to deal with pipes of different diameters according to the number of units. Several experiments are conducted in pipes of different diameters, and the effectiveness of the mechanism of the robot is confirmed.

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This paper presents a collision force suppression mechanism. The mechanism is composed of an electromagnetic clutch and a rotary damper. The mechanism is installed on the shoulder and elbow joints of a manipulator, respectively. Also, the manipulator is installed on an omnidirectional robot base. If the manipulator collides with an object, the joint axes of the manipulator are separated from the electromagnetic clutch, and collision forces are suppression by the damper without any control. Through collision experiments, the effectiveness of the mechanism is verified.

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In recent years, concern for the safety of food is growing, and interest in organic farming is increasing. In Asia, as one of environment-friendly organic farming, rice-duck farming was been practiced for more than twenty years. It is the integrated farming of rice and duck. The farmed ducks are put in the paddy field and eat weeds and pest insects. However, the effect of their weeding and pest control depends on their field of activities. To improve the efficiency of the weeding and the pest control, a radio-controlled duck robot for guiding farmed ducks around the whole paddy field was developed in the previous works. This duck robot can guide farmed ducks with clucking, wing flapping, and feeding. The aim of this study is to improve the robotic guide duck to be able to autonomously locomote between rice sequences. A camera and a microprocessor installed in the autonomous duck robot is sending the image data to the external personal computer by Bluetooth, and the external personal computer processes the image and the control information is calculated. Then the external personal computer is sending the control information to the microprocessor installed in the autonomous duck robot by Bluetooth, and the microprocessor controls the crawler for locomotion on the soft ground. From experimental results in the paddy field, the obstacle avoidance performance was verified.

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In the finish processing of limited production of diversified products, it is expected that development of bilateral control robot that realize finish machining complex shapes. However, if we apply a bilateral control system, it is very difficult work because worker must move while being constantly in contact with the slave tool. So, in this paper, we propose a method to show the shape of the work piece from the estimated curvature. Then we propose a method to show the shape of the work piece from the estimated curvature. And we build a support system for processing adapted proposed method. The system is consisted of a 6-DOF parallel haptic device as a master robot and 4-DOF parallel robot as a slave robot. The effectiveness of the proposed method is shown through an experiment.

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The purpose of this research is the planning of walking trajectory for quadruped robot in response to obstacle environment. If quadruped robot adjusts stepping points to step over obstacles, the robot can avoid obstacles more smoothly. So we optimize stepping points for walking in obstacle environment like an animal. Generation problem of stepping points is reduced to a combinatorial optimization problem solved by using genetic algorithm. Learning data for neural network are information of obstacle environments and optimum stepping points. Optimum stepping points for learning are generated by genetic algorithm to variety of obstacle environments. Obstacle environments in this report have different configurations and different lengths. After learning optimum stepping points and obstacle environments, unlearned data are input to the neural network. The output data to unlearned input data is the valid stepping points. The proposed method of walking trajectory planning can generate stepping points to unlearned environments.

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Metal spinning is a plastic forming process for forming the rotational shapes. In the process, the blank attached on the rotating mandrel is pushed by roller, and formed. This process is more suitable for high-mix low-volume production than press forming. Recently, several studies on forming non-axisymmetric shapes have been published. However, the shapes are limited to non-cylindrical shapes. In this study, synchronous multi-pass metal spinning for non-axisymmetric shapes such as rectangular box shapes is developed. In this method, position of roller is controlled synchronizing with the mandrel shape. To calculate the tool path easily, it uses the measurement of the mandrel shape using impedance control, and linear interpolation between the blank shape and the mandrel shape. This paper reports the forming experiments which made some non-axisymmetric shapes from thin aluminum sheets.

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Growing garden products involves a lot of work, such as harvesting, which is difficult to mechanize. Garden product crops require longer working hour compared with rice. We are developing a robot performing soil sterilization aimed at preventing repeated cultivation disorder. This robot is a medicinal solution injection robot injecting chloropicrin to use for soil sterilization automatically. The developed robot is driven by oil pressure actuators, runs on crawlers, with an chemical injector mounted in front of the robot. The robot is equipped with a triangular surveying sensor. The robot covers entire working soil area with a combination of straight lines and arcs along which the position and orientation of the robot is compensated by the output from the sensor. Experiments were conducted to demonstrate that the robot can navigate on the uneven and soft terrain within required position errors.

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We developed compact type Cleaning Robot. The robot cleans office area. In General, office area is larger than common area in office building. But, office area is cleaned by a lot of human, now. So there is requirement of autonomous cleaning system in office area. Office area is often moved desks and cabinets. The robot run automatically by triangular surveying sensor and reflectors. By the report, we show the concept of the robot.

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The paper describes practical design and use of a Cleaning Robot for Vessel. We developed an autonomous Cleaning Robot, which is equipped with a gyroscope sensor, a triangular surveying sensor, and a communication device. The robot uses the gyroscope sensor and odometery to calculate its current position. The triangular surveying sensor, together with reflection panels strategically placed in the environment, is used for calibrating and improving the accuracy of the calculated position.

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To lighten driving motor is an important problem for the robot, and a light ultrasonic motor is expected. However, it is not possible to use it as a servo drive motor because the velocity range is narrow, and especially there is no continuousness in the low speed region of the positive or reversal. Then, the improvement of the lowest rotational speed was attempted by superimposing the voltage of a frequency different from the motor drive frequency. The rotational speed fluctuation was measured as the evaluation characteristic. As a result, it became clear that the rotational speed fluctuation is low as for superimposing a frequency away than driving frequency.

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