Flow-induced vibration of a fluid conveying pipe with a spring supported end, is examined theoretically and experimentally under the condition that the fluid velocity has a small pulsating comnonent. The parametric resonance of the lateral deflection of the pipe is occured due to the pulsating flow. In this paper, two first-order ordinary differential equations, which govern the amplitude and phase of the parametric resonance, are derived from the nonlinear nonself-adjoint partial differential equation by the Liapnov-Schmidt reduction. The effect of the spring support on the nonlinear stability is discussed with the reduced evolutional equation, which is obtained with the method of center manifold. Furthermore the experiments were conducted with the silicon rubber pipe conveying water. The lateral deflection of the pipe was measured by the image processing system which was based on the images from two CCD cameras. The typical feature of the parametric resonance, which was predicted in the theory, was confirmed qualitatively.

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This study is concerned with the motion and vibration control strategy for a flexible-link mechanism in order to achieve high performance and stability. Reducing vibration and making positioning time faster are simultaneously required in this system. Technology of smart structures is introduced in the flexible-link system to conduct the vibration control. The smart flexible-link is composed of the two flexible-links and the piezoelectric films which have the sensor/actuator function for itself, and so its mechanism is extremely suitable for controlling the vibration. First, a modeling method of the flexible multibody systems is presented based on a functional modeling method and modal analysis. An approach for hybrid control of motion and vibration is proposed, in which a large magnitude and slow vibration is controlled by the servomotors and a minute vibration is controlled by the piezoelectric films. The motion and vibration controller for the servomotors is designed with the mixed H₂/H_∞ control problem and the vibration controller for the piezoelectric films is constructed by a direct velocity feedback, resulting in the enhanced performance on the motion and vibration control.

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Ultrasonic motors (USM's) have some special unique features, such as high-torque under low-speed operation, compact size, and no electromagnetic noise. The USM is expected to apply an element of the artificial muscle. The basic driving principle of the USM is based on friction force between a rotor and a stator. Therefore, it is difficult to drive the USM at a constant speed, because the generation of heat by friction changes the friction force. In this study, we constructed a real-time system of the USM by RT-Linux to develop an artificial muscle. And, we proposed a speed controller of the USM, considering the temperature rise of the USM. In the results, this method was proved the most effective for the speed control of the USM in experiments.

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The container crane of the harbor received the enormous damage in the Hanshin Awaji great earthquake disaster. For the establishment of the earthquake-proof reinforcement quay, there is the container crane with vibration isolation system in practical use. We have proposed the rocking type of vibration isolation system as a new technique instead of the horizontal type of vibration isolation system which have been used in buildings and bridges. The purpose of this study is to examine the performance of the rocking type of vibration isolation system and to present its seismic design method. We analyzed seismic responses for various earthquake waves by three-dimensional FEM analysis, and compared the rocking type of vibration isolation with horizontal type. The result clearly shows that the rocking type of vibration isolation is able to isolate for the twist vibration mode by setting of the damper or using the stabilizer, and the design of the rocking mechanism is easier than horizontal type. In addition we presented the dynamical optimal design method of its damping by using two DOF model.

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A numerical method is proposed to calculate damping properties for sound-proof structures involving solid body, porous media and air in two dimensional regions. Both effective density and bulk modulus have complex quantities to represent damped sound fields in the porous media. Particle displacements in the media are discretised using finite element method. For solid body, displacements are modeled using conventional finite elements including complex modulus of elasticity. Displacement vectors at common unknown varriables, are solved under coupled condition between solid body, porous media and air. Further, explicit expressions of modal loss factor for the mixed structures are derived using asymptotic method. The proposed methods yield appropriate results for some sample problems. Moreover, it is found that damping can be coupled in the mixed structures.

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This paper deals with the development of a new method for determination of powder form materials in plastic bag by sound. It is useful to determine the kind of powder form materials in the opaque plastic bag without open or contact. This detector utilizes the variation of the amplitude of the frequency response within entire acoustic system. The incident impedance of powder form materials varies with the diameter of particles and so on. For contactless determination, small distance gap between face of detector and plastic bag is adopted. Characteristic acoustic impedance and complex wave number are measured by the transfer function method. These measured parameters of powder form materials are introduced into theoretical analysis. The trends of the experiments and theory show good coincidence.

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The behavior of solid spherical particles and air bubbles moving in an ultrasonic standing wave field are investigated experimentally. An ultrasonic transducer of 45 kHz is fixed at the part of the wall of the vertical square channel, and a standing wave field can be formed horizontally in this section. Several small pipes are inserted in this channel and particles and bubbles are dropped or raised into the pipes respectively. In the experiment for solid particles falling or rising in a liquid, the average terminal velocity in an ultrasonic field is slower than that in which there is no ultrasonic field. In the case of bubbles, the path of spherical bubbles in pipes strongly changes depending upon which position (node or antinode of sound pressure) in the standing wave field it passes. The rising velocity of non-spherical bubbles is faster than that of those with no ultrasonic application since the shape of bubble is deformed into a prolate ellipse by the ultrasonic radiation force and the drag coefficient of bubble decrease.

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Some practical systems are expected to track reference signals with unknown properties. For such systems, we propose a new design method of discrete-time adaptive servo systems. The method is for SISO-LTI systems. In the method, two types of Diophantine equations are used ; one is for designing feedfoward controllers, the other is for feedback ones. The feedfoward controllers are adjusted to the reference signals, while the feedback ones are adjusted to input and output signals of plants. Although the method requires unstable plant zeros to be known, we can use the idea of limiting zeros when sampling period is sufficiently small. Hence the method is applicable to most of unknown plants in continuous-time domain. The method considers unknown deterministic disturbances also. Application results to a pneumatic servo system show the effectiveness of the method. The results are compared with those of PID control systems.

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This paper describes rotational control and swing suppression of a crane suspended load model. A rotational free rigid body suspended by a single rope is controlled using three inertia rotors. Fiber optical gyros installed on the suspended load are used to measure the load orientation angles. Controlling angles and angular velocities are obtained from measured data using the conversion between zxy and zxz Euler angles and the driving system of the inertia rotors are developed based on the coupling dynamics. Experiments and simulations show that the rotational orientation is controlled without problems, but swing control is possible under some limit conditions of the load mass size and the rope length, since the gravity force act on the swing motion.

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A pneumatic servo-system has essentially non-linear elements such as compressibility of air, friction between cylinder and piston. The control scheme with fuzzy inference is effective for such non-linear plants. However, fuzzy rules in the fuzzy controller should be adjusted optimally to realize excellent control performance. 0n the other hand, the genetic algorithm can easily obtain the optimum solution in optimum problems. In this paper, we propose a fuzzy control for the vertical type pneumatic servo system in which the antecedent clause in the fuzzy controller is optimized by the genetic algorithm. In the genetic algorithm, a penalty function which regulates an excessive overshoot and a vibration of the plant output is proposed. Further, the effectiveness of the optimized scheme was confirmed by experiments using the existent vertical type pneumatic servo-system.

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In order to obtain more effective coordinated behaviors against changes in environments or unlearned environments, we here propose a new fusion unit using external sensor information for a fuzzy behavior-based control system trained in the framework of module learning. The present fusion unit falls into a class of adaptive priority-based architecture in which the fusion between behavioral elements is carried out by a cooperation or comnetition strategy, depending on whether an objective point or obstacle can be detected or not. Some experimental results of a miniature mobile robot Khepera show that the proposed metcod is superior to the conventional method that applies a fusion unit based on a fixed priority-based architecture.

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While magnetically suspended sliders controlled five degrees of freedom have been used as a linear guide system for wafer transportation in clean atmosphere, three degrees of freedom controlled sliders may be applied to suspensory equipments which can move along a ceiling board without an effect of friction. Space saved and reliable suspensory equipments are very helpful for transporting handicapped people to take care of. In this paper, fault-tolerant control system using an observer for magnetically suspended sliders is discussed and the design method for the observer which can function in replacement of outputs caused by isolation of faulty sensors is proposed. In experiments, some disturbance signals are added to a displacement sensor and the responses are measured. Sensor faults are successfully detected and isolated by the designed diagnostic system for abrupt disturbances.

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This paper proposes neural network controllers using a reference model and investigates their characteristics. Since the neural network compensates the incorrectness of the plant such as nonlinearity and uncertainty against the reference model, a conventional controller can be designed based on the known dynamics of the reference model. The neural network controller can be classified into three types in terms of the connection between the neural network controller and the conventional controller. In the D-type controller, the output from the conventional controller inputs to the neural network and the reference model in parallel. In the Y-type controller, the output from the conventional controller inputs to the neural network, the plant and the reference model in parallel. The neural network of both controllers learns the combination of the inverse characteristics of the plant and the forward characteristics of the reference model. In the I-type controller, the output from the conventional controller inputs to the reference model whose output inputs to the neural network. The neural network leams the inverse characteristics of the plant. Simulation results using nonlinear plants show the achievement of the neural controllers and confirm their effectiveness for controlling the nonlinear plants.

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We propose a new way to disperse planning route of transportation using IVC (Inter Vehicle Communication) in this paper. VICS (Vehicle Information and Communication System) has been developed to solve the traffic jam which is one of the ITS (Intelligent Transportation Systems) technologies. The VlCS is able to provide real-time global information with drivers and navigation system which helps drivers to find the fastest route according to the current traffic conditions. However, it is afraid that spatial oscillation of traffic jam "hunting phenomena" will happen if most of cars follow given global information with time delay from VICS. 0n the other hand, IVC is a developing technology which enables cars to exchange various information with others by optical communication, millimeter electromagnetic waves and so on. We therefore propose the combination way to decrease traffic congestion using IVC and VICS. At first we show the hunting phenomena in numerical simulations and the relationship between hunting phenomena and VICS user ratio. We propose a way to disperse planning route by IVC, and then confirm effect of the proposed way in city traffic models in numerical simulations.

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It is often said that it might be very important to take Kansei, some kind of human sensuous inspiration, into account of design. And it becomes more and more important especially in the design of products whose functions are saturated and it becomes difficult to gain competitive power only by adding a new function. In those cases, it is difficult to gain competitive power by discounting its prices nor making efforts is human engineering sense of ease in handling. In such cases, visual design will be more important, so that visual designers become key of success in the product. However, Kansei design used to be based on questionnaires to the customers, and it is basically based on putting emphasis on the greatest common of them. But, in most of cases visual designers would like to show their feelings into design and lead majority to his or her sense. So that Kansei design database is often useless to them and it is sometimes obstacle for their creativity. In this paper, we will propose the Kansei design system which is based on image processing system and qualifying image by using Fourier transform and make up a new visual design by using those Fourier transform data. As an example, we have used the proposed system in design of doors. We have verified the results by inspiration test and brain test and showed a possibility of the proposed method.

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The novel algorithm for the kinematic and dynamic analysis of closed loop mechanisms has been developed. By determining a basis of the motion space of each loop of a mechanism by using the axes (screw coordinates) of passive joints in it, velocities and accelerations of passive joints can easily be represented as a function of those of active joints. These computations can be performed by solving the linear equations which were divided into several groups. The computational cost is reduces by this division. Closed form equations for force analysis and dynamic analysis can be easily derived utilizing the coordinate vectors of joint axes on the above bases.

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Conventional fluid motors require high-pressure fluid (10 MPa∼) and the rotation speeds of these motors are extremely high (10, 000 rpm∼). Therefore, it is difficult to apply these motors to mobile robots. This paper describes a new fluid motor composed of new mechanisms. The motor consists of two crown gears and 3 or more cylinders. It is named 'Crown Motor' after the two crown gears, the precession gear and the output gear. The precession gear is driven by the cylinders meshing the output gear. In each cycle, the output gear rotates an angle equal to the difference of the numbers of teeth between precession and output gears divided by the number of teeth of the output gear. With this mechanism, compact size and high gear ratio can be obtained. Thus, a high-torque fluid motor with slow rotation speed is accomplished. The rotation speed of the motor can be continuously controlled from CW (max) to CCW (max) by changing the timing of valve opening, similar to the sequence of electric DC brushless motors. ln addition, the Crown Motor can be driven with low- pressure fluids, such as tap water (0.2 MPa∼). Two control systems of Crown Motors are proposed in this paper. One is with conventional electric valve system (stepping drive system) and the other is with new mechanical valve system without any electric device (self-excited drive system). With stepping drive system, Crown Motors can be used as a stepping motors with one-by-one cylinder operation. On the other hand, self-excited drive system is proper and reliable if water is used as driving fluid in practical applications. In general, high-torque motors with free or lock states available require large clutches or brakes. However, the prototype of Crown Motor achieves both states without any additional components. With these properties, Crown Motors can be used in not only mobile robotic applications but also other various applicatlons. The prototype accomplished a high torque of 16 Nm at 15 rpm under 0.5 MPa and with efficiency of 35%.

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We propose an interconnected suspension mechanism applicable to rough terrain mobile robots for construction site and such. All wheels can follow on uneven ground by moving mutually with the interconnected suspension mechanism. And it is possible to control simply the posture of robot using the mechanism. In this paper, the structural and mechanical characteristics of the mechanism are discussed and the ground contact loads of wheels are analyzed. It was confirmed the mechanism has enough ability at moving on uneven floor and posture control by experiments with an experimental rough terrain moving robot.

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Application of force display system is expeded over the various fields such as tele-operation, medical care training and amusement. The control system that uses kinematic information for displaying force is adopted in almost force display systems developed for commercial products. However they have been troubled by low stiffness, backlash and so on in drive system. High stiffness, small backlash and little friction loss are needed for the high performance of the force display system. We compare the characteristics of three drive systems : wire drive, flat belt drive and timing belt drive that are well used for force display system. From the comparison of the three drive systems, it was known that the timing belt drive is suitable force display system. Additionally, we suggested a compact-type timing belt drive that realized low system inertia and showed the compact-type is the excellent drive system for force display system.

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When the mammals walk or run, they use energy which stored in tendons when they swing their limb. In this paper we concentrate on the gait of the horse, especially a trot. The purpose of this study is to realize horse-like trot gait by a quadruped walking robot. Equine fetlock joints have important role when they are walking or running. The change of angle of the fetlock joint makes the tendons stretch. When the tendons stretched, they store up energy. First, a model was proposed to realize horse-like gaits by a quadruped walking robot. Next, the quadruped walking robot PONY was designed and made.

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The mammals use energy which stored in tendons when they swing their limb. In this paper we concentrate on the gait of the horse, especially a trot. The purpose of this study is to realize horse-like trot srait by a quadruped walking robot. The change of angle of equine fetlock joint makes the tendons stretch. When the tendons stretched, they store up energy. Motion of fetlock joint is not controlled actively by muscles but controlled passively by tendons. Authors have made a horse-type quadruped walking robot PONY. The PONY has actuator systems for fetlock joints which a motor and a spring connected in series. This system corresponds to equine muscles and tendons for example a superficial digital flexor muscle. ln this paper, first, simulation experiments showed that effect of the motor-spring system. Next, the PONY realized horse-like trot gait.

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This paper deals with a kinematic stability analysis of circle formation that emerges through interaction caused by local vision and obstacle-avoidance action in multi-robots. Individual robot has a specific, limited range of signal communication to detect other robots and, according to the location of other robots detected around each robot, the robot takes an action such as proceeding forward or turning left/right at particular angle for each time step. This action selection algorithm is implemented into each of robots. By changing the turning angle and vision angles, computer simulation of group behavior in the multi-robots is carried out and we find rather stable circle formation emerged in such robotic system. In order to analyze the kinematic stability of the circle formation, we propose a circle formation model that represents the ideal circle to be generated by multi-robots, and examine theoretically the stability of the circle formation in terms of the vision angles, the turning angle, and robot number forming a circle. The theoretical results are also examined by computer simulations and a good agreement is shown between the both results.

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A decentralized data association is presented for 3D dead reckoning in a modular omnidirectional vehicle. Wheel units assembled into the vehicle partially estimates the vehicle position based on their own onboard sensors. The partial estimates are exchanged among the units and fused in a decentralized manner. Then the units can precisely identify the vehicle position. The dead reckoning algorithm is formulated based on the information filter and the Covariance Intersection to effectively integrate the partial estimates without taking into consideration their correlation. The unscented transformation is also exploited to predict the vehicle position without linearizing the nonlinear model related to the vehicle motion. The proposed method brings highly modularity and extendibility in the dead reckoning system. Experimental results validate that the proposed dead reckoning provides better positioning accuracy than the conventional Kalman filter-based method does.

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This paper proposes a multi-model based approach to detection and diagnosis of hard/noise failures of internal sensors in mobile robot. Three system modes (normal mode, hard failure mode, and noise failure modes)of each sensor are modeled. Changes of the three system modes are also modeled as switching from one mode to another in a probabilistic manner. The mode probabilities and sensor outputs are estimated based on a bank of Kalman filters, and they are interacted with each other effectively. To provide better fault decision, the model sets are switched according to the robot motion. The proposed fault detection and diagnosis (FDD) algorithm is formulated based on the variable structure interacting multiple-model (VSIMM) algorithm. The FDD algorithm is incorporated into a dead-reckoning system of our mobile robot with five internal sensors (four wheel-encoders and a yaw-rate gyro). Experimental results show that the FDD algorithm gives the correct fault decision of the sensors and the dead-reckoning system allows the robust self-localization of the robot subject to sensor failures.

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In this paper, a motion planning for a manipulator, which is equipped on an autonomous underwater vehicle (AUV), is proposed. This approach is composed of the path planning of the tip position of the manipulator and the posture planning of it. In the path planning, an objective tip position is generated using the genetic algorithm. And in the posture planning, a manipulator's posture to avoid obstacles is decided by an evaluation considering the drag force. The manipulator is able to move safely and suitably because each planning is executed repetitively. The validity of this approach was shown in an experimental environment setting a moving obstacle and a stationary obstacle.

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The ETS-VII is the first unmanned satellite with robot arm in the world. Three types of force/torque control functions based on active compliance control were applied to the robot for on-board local compensation of tele-operation and autonomous dexterous task operations. Various robot experiments for on-board servicing technology were conducted successfully with using the force/torque control functions. This paper describes the force control methods, results of flight experiments using the functions and their evaluation.

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This paper discusses the manipulation of multiple objects by pushing. When manipulating multiple objects, the relative motion between two objects such as sliding and rotating may occur. We propose a velocity based pushing method where the region of the pusher's velocity causing the desired relative motion at each contact point is obtained as a common space of regions causing the relative motion at one of the contact points. Experimental results are also included to show the effectiveness of our idea.

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In this paper, we propose a decentralized motion control algorithm of multiple mobile robots for transporting a single object in coordination. In this algorithm, each robot is controlled as if it has a caster-like dynamics and transports a single object in coordination with other robots without using the geometric relations among robots. The proposed control algorithm is experimentally applied to multiple omni-directional mobile robots. Experimental results illustrate the validity of the proposed control algorithm.

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In order to give more adaptability to a multiagent system, it would be desirable for each agent to have some kind of online learning ability for how to help and guide the other agents, i.e., how to cooperate with each other for the purpose of achieving a task which is given to the whole system. When we browse the field of computational methods of online learning, reinforcement learning seems a good candidate for this mechanism. However, due to the theoretical limitation that it assumes that an environment is Markovian, traditional reinforcement learning algorithms cannot be applied directly to this behavior acquisition problem in a multiagent environment. In this paper, an online learning mechanism is designed by using two reinforcement learning units. The first one is for predicting the move of the other agents at the next time-step, and the second one is for building the appropriate action rule set for an agent itself. Several computer simulations of the cooperative carrying problem are conducted to investigate the effectiveness of the proposed approach.

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The purpose of this study is to clarify the condition of being "gentle swinging to the human" or "comfortable swinging". At first, a rocking chair drive unit was developed, and features of the comfortable swinging were investigated by driving the rocking chair with various waveforms relating "1/f fluctuation". As the result, the swinging evaluated with comfortable was the model motion of rocking chair with constant period in which the amplitude was fluctuated in the relationship of 1/f fluctuation. Next, this comfortable swing was examined by the semantic differential technique and it was clarified that the epithet pairs were classified into three factors. Then, the 16 scales questionnaire on the comfortable swinging was proposed, and the effectiveness was confirmed by the questionnaire survey. In addition, the active rocking chair realizing the comfortable swinging by the simple equipment was developed, and the comfortableness was confirmed by proposed questionnaire.

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FEM analysis is a useful method to discuss the deformation and failure phenomena for synchronous belts. In this study, stress and strain behavior in synchronous belts is analyzed by using a general non-linear FEM program. The calculated results are compared with some experimental data that are measured under fluctuating and constant torque conditions. The difference between these conditions is reasonably simulated by using the FEM analysis.

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Differential gear is used in the purpose to make turn over at the automatic car. Then, the differential gear is generally composed of plural bevel gears. Because plural bevel gears in the differential gear mesh at the same time and the structure is complicated, there are few studies for each bevel gear. The axial hole diameter of the differential pinion becomes slightly bigger than the gear shaft diameter to turn around the shaft. The interval between the axial hole and the gear shaft is thin, so it is necessary to take an influence with this special shape into consideration. Therefore, in this paoer, the approximate formula with the deflection influence function of the differential pinion tooth in revolving was made in considering the special shape as mentioned above. Then, the load distribution on the contact line of the differential gear tooth was calculated by using the influence function. Moreover, the bending moment influence function was derived and tooth root stress was calculated. Effects of the axial hole of the differential pinion on load distribution and tooth root stress are clarified. These calculated values were compared with the measured values, and validity this calculation method was examined.

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The triple arm mechanism, which consists of a base link, a coupler link and three two-link-chains (arms) having the actuated prismatic joint, is a basic spatial parallel mechanism with three degrees of freedom. In this paper, a method of forward displacement analyses is proposed for such a general triple arm mechanism that three revolute pairs are attached to the base link at any attitude angle. Root diagrams of the spatial parallel mechanism of this type are drawn in order to show its motion behavior for one input displacement constantly increased and sensitivity curves of angular displacements of three arms with respect to the kinematic constant are calculated. The spatial parallel mechanism that the direction of the spherical joint socket is adjustable is designed in order to spread the domain of motion of the coupler link. Position errors of the spatial parallel mechanism under a load perpendicular to one of arms are measured. Such a new observation is shown that position errors increase radically for changing one of input displacements at the position apart from limit positions where the determinant of the Jacobian matrix is zero.

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This paper deals with investigating the influences of kinds of high-speed steel hob substrates fully coated with (AI, Ti) N on a behavior of crater wear mainly, flank wear and finished surface roughness in dry hobbing. Experiments were carried out using fly tools, which were made of normal high-speed steels (HSS) and powdered metal high-speed steels (PM-HSS). As a consequence, the following points were clarified : (1) The HSS tools retard the occurrence of crater wear in comparison with the PM-HSS tools, and among them, the corresponding to SKH 55 and M 34 tools are effective for the crater wear. (2) It was suggested that the crater wear mechanism on the coated rake face of all hob substrates is that first, the delamination and/or the seizure of the coating film by the deposited metal takes place, and after appearing the substrate, the crater wear increased by the abrasive action with the cutting chips. (3) Among the hob materials tested, the corresponding to SKH55 HSS tool is suitable in terms of the crater wear, the flank wear and the surface finished in dry hobbing.

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In order to measure correctly the strain distribution on sliding surfaces of machines, the strain sensor should react only to the strain to be measured. Thus, the sensor should be insensitive not only to pressure, temperature, transverse strain and must be made to meet requirements regarding small size. In this research, we developed a small sputtered thin-film strain sensor with negligible sensitivity to pressure and temperature by properly proportioning the sensor constituents with a Ni-Cr-Al alloy. In addition, by implementing an L-shaped sensor in an appropriate size, a transverse strain sensitivity of zero was achieved.

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A new forming process, extrusion-burring process is proposed to produce the parts with a flange from a thick plate. The feature of the newly devised extrusion-burring process has been investigated in detail by FEM analysis and verified by a series of experiments with the aluminum plate. In the extrusion-burring process, a drawn cup is extruded by pushing its wall downwards and the extruded material flows into the flange portion. With increasing extrusion stroke the material of the flange portion gets thick and high. By increasing extrusion stroke, the flange height after burring process increase successfully. However, an excessive extrusion stroke results in the fracture at the base of the flange portion, because the burring process is very similar to the ironing process.

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NC machine tool driven by NC programs is very useful to machine standardized products with high accuracy and productivity. However, conventional NC machine tools have no function to change cutting conditions during machining operations by themselves because NC programs instruct all cutting conditions before the operation. This is the biggest problem to realize an autonomous NC machine tool. To realize an autonomous NC machine tool, a new architecture is required to operate an NC machine tool without NC programs and to adapt cutting conditions in real time to maintain stable machining operation. This paper deals with implementation of a feedback machining control using digital copy milling system, which consists of function to generate tool paths in real time and machining strategy to adapt cutting conditions. The proposed digital copy milling system is verified to show its ability in cutting experiments.

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For a peg-in-hole task in order to achieve more quickly and automatically interpositioning the objects we have developed such kind of remote center compliance devices as the spring and rubber mechanisms cooperating with the feedback systems by sensing load on the manipulator hands. We have evaluated the experimental performances of the friction forces, the friction coefficent and the effectiveness for the size of chamfers in respect to the clearances between pin and hole through the compliance robot hands. These test results have been evaluated to derive a criterion of the spring stiffness of RCC devices in practical uses.

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This paper describes the cooperations method by knowledge exchange for AGVs autonomous moving in the autonomous decentralized FMS. The method gives AGV an individual knowledge called AGV knowledge and, by exchanging the AGV knowledge, each AGV can avoid the collisions. This method is not the conventional control by a host computer but the communications between AGVs. After applying the developed method for the 9 types FMS constructed in a computer, the number of head-on collisions are deleted.

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