We propose a simple and easy robot teaching method. It is based on "teaching-by-showing" technique with a structured light approach. In this method, the first step of the teaching process is camera and projector calibration. The second step is a demonstration of manipulation by a human in front of the robot with a random pattern projection. The third step is obtaining range images of the object, and calculating the position and orientation of the object from the range image. In this way, we can obtain a path of the object and make robot motion to reproduce it. We examined the accuracy of range images and obtained positions and orientations of an object. In teaching experiments, a robot reproduced paths demonstrated by a human successfully by using this method.

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We have proposed an robot controller architecture to easily build up a robot controller. The controller has 7 agents and 3 databases. The agents are Man-Machine Interface, Task Planner, Motion Planner, Arm Controller, Tool Controller, Visual System and CG Display. The databases are Task Knowledge Database, Environment Database and Robot Database. We are developing software of agent like Open GL. We think that if we use thins Architecture, we can make a robot easily. This paper show work plan as sample of A Robot Controller Architecture and Pick And Place.

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In this paper, we propose a method to construct different configuration master-slave robot arms system by two commercial industrial robot arms. This system is controlled as unilateral in case a slave arm is not interfered with its environment ; however, it is controlled as bilateral in case of interference. The dynamical characteristics of proposed system and a singular point avoidance procedure necessary for the master arm operation are also discussed.

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In assembly operation, force control is necessary as well as position control. Rigidities of the arm, the contact body and the force sensor influence the position/force control, but there are many cases that rigidities are unknown. In this study, we have used a three-link whose end-effector has a spring for making position/force control easy. We present simulation results using velocity/torque control, in which the tip position of the arm is controlled to follow the desired trajectory along with the constraint cylindrical curved surface wall and the tip reaction force that is perpendicular to the curved wall is simultaneously controlled.

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The authors have studied a controller design method based on functionality. The method is to design a large-scale control system as a combination of small detachable components. This paper extends the method to exception handling. The main issue in the study is that discrete inputs due to variation of control structure degrade the control performance. Hence the study discusses how to solve the issue.

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This paper describes a method of modeling based on multibody dynamics (MBD) and autonomous control of a dual-arm robot with a stereo camera. Each arm of the robot has seven degrees of freedom as human. It is easy to set up the three dimensional motion equations with one of MBD. The model of the robot is derived by using the MBD. The controller of the robot is composed of LQI controller and gravity compensation. Gravity compensation is designed by the MBD model. The positions of handling objects are obtained by 3D and color data of stereo camera. We test effectiveness of our proposed method by experiment.

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We propose a new weight compensation mechanism with a non-circular pulley and a spring. We show the basic principle and numerical design method to derive the shape of the non-circular pulley. After demonstration of the weight compensation for an inverted/ordinary pendulum system, we extend the same mechanism to a parallel link manipulator, analyzing the required torques with Jacobian matrices. Finally, we carry out hardware experiments.

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This paper describes cable height measurement & database system using a single camera and 3D environmental model. The proposed Mobile Mapping System (MMS), featuring the carrier phase D-GPS/DR(Dead Reckoning)combined navigation system and the GPS-Gyro/IMU(Inertial Measurement Unit), performs highly accurate positioning performance in centimeters and posture estimation at 0.073[deg](1σ) for heading, 0.064[deg](1σ) for pitch and 0.116[deg](1σ) for roll. As a result of the evaluation test, the difference between the conventional method and the proposed one was less than 10 [cm]. Moreover, the aerial cable database, which can be made using the obtained 3D data, is proved to be valid and effective for the continuous aerial cable maintenance work.

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This paper describes tunnel cross-section measurement system using a Mobile Mapping System. The topography of Japan is mountainous, so there are many tunnels in Japan and total length of Japanese tunnel on road is over 3000 km, and 80 km tunnel are built every year. As far as some old tunnels are concerned, collision accidents sometimes happens because of old tunnel's diameter shortage. Thus, tunnel cross-section measurement method without highway traffic regulation is demanded nowadays. The proposed Mobile Mapping System (MMS), featuring the carrier phase D-GPS/DR (Dead Reckoning) combined navigation system and the GPS-Gyro/IMU(Inertial Measurement Unit), performs highly accurate positioning performance in centimeters and posture estimation at 0.073[deg](1σ) for heading, 0.064[deg](1σ) for pitch and 0.116[deg](1σ) for roll. The proposed Mobile Mapping System that can measure 3D shape of the tunnel at 40 km/h cruising speed without traffic restriction is proved to be valid and effective for tunnel cross-section maintenance through field experiments

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In recent years, active safety technologies of cars are becoming important and the cases that cameras are mounted in cars are increasing. Since the perception of the distance of a usual image is difficult for drivers, method to construct overhead view images and assist drivers are proposed. In this paper, we propose methods for estimating camera parameters of multiple cameras and construct overhead view images with small errors. Effectiveness of the methods is examined by experiments.

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We developed weight balanced which we calling "Portable Field Arm". The arm has a reach of 3 meters, possesses 5 Degrees of Freedom, and is easily assembled /disassembled. Because of its compact body, it's easy to transfer. It is a multi purpose arm but in this paper we show configuration as a evaluation setup for metal detectors. This paper explains the arm's mechanism and its positioning accuracy.

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The multi-purpose hexapod robot COMET-IV which we have developed is driven by hydraulic power. In general, mobile robots are operated by remotely human. It is necessary for mobile robot to achieve safety walking and a high trajectory performance in unknown outdoor environments. The system consists of omni-directional image camera and joystick that is tool for walking instruction, and we use a WLAN. Arbitrary viewpoint image generated from omni-directional video stream is exhibited to user. In this paper, we propose Tele-operation system of hexapod robot COMET-IV with real-time gait and trajectory planning. And by experiments, we confirm the efficiency of proposed system.

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This paper presents the locomotion method for hydraulically actuated hexapod robot in rough terrain. We develop the hydraulically actuated hexapod robot named COMET-IV which operates for hazard operation assistance in outdoor. Outdoor fields consist of various environments, so the robot must have high adaptability to the ground. Conventional method, position control, has difficulty to adapt to them. So we apply the position/force and attitude control to the COMET-IV and the locomotion test in outdoor field is done. The effectiveness of the control system is shown. And it is necessary for COMET-IV to walk on the gradient of 20 degrees, which is one of the design specifications. The gait planning and motion of the body is discussed and the presented method is verified through the locomotion test of the gradient of 10 degrees.

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This paper is relation to way points tracking on uneven terrain of the Hexapod robot COMET-IV which is 2.5 meters long, 3.3 meters wide, 2.8 meters high and approximately two thousand kilograms. Recently, many autonomous robots have been developing to be helpful for people in the world. The autonomous robot which moves outdoors must have the good trajectory tracking control. But, it is not easy for COMET-IV to achieve the good trajectory following performance because of a soil deformation, a foot slippage due to the heavy robot and big size. This time, we apply a way point tracking control to the COMET-IV for an autonomous robot.

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This paper described a method for obstacle avoidance of a hydraulically actuated hexapod robot COMET-IV. This robot is an autonomous robot to assist during hazardous operations in the outdoors. First, a gait planning method to walk in omni-direction with a circular gait and a crab gait is shown. The effectiveness of the gait planning method is shown by the results of a lane change walking test and a zigzag walking test in the outdoors. Considering the tracking error of COMET-IV, we developed the navigation system which consists of real time terrain scanning with laser range finder and path planning. Finally, we introduce the elementary experiment of obstacle avoidance in the outdoors.

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This paper presents the autonomous locomotion method with stereo vision camera in vertical step. It is necessary that a three dimensional recognition in the vertical step, which for COMET-IV to autonomous walk on the vertical step locomotion. We construct the navigation system with stereo vision camera for getting three dimensional data of the locomotion enviroment. We will report the experiment result.

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We have developed an interface that can superimpose tactile information onto surface or images displayed on a computer monitor. The interface is composed of a small vibrator mounted on user's nail and sensor to measure surrounding information. When the finger is moved, the vibration is provided according to the information form the sensor, and the vibration can be perceived as the stimulus from the finger pad, instead of the stimulus from the nail. Although wearable or environmental sensor had been used for the interface, they could not be compatible. In this paper, we achieved the wearable system, which can applicable to both wearable and environmental sensors.

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Considering tactile sensors there are two ways to acquire object information. These are spatial sensing with two dimensional devices and fast sensing with simple devices. Because the reflection-type tactile sensor uses a reflection image, both methods can be employed. Though there exist some dynamic characteristics in these two ways. In this study, we first validate the hysteresis of the reflection-type tactile sensor. The results show the sensor can evaluate displacement less than 2 mm. Then we propose a novel interface called "fibratus tactile sensor." Secondly we construct a fast sensing device using reflection image and a combination of light emitting diodes (LEDs) and photodiodes (PDs), and validate the sensor's reactivity. It can distinguish 300 ms interval between two signals. Moreover the correlation between the standard deviations of the acquired outputs from the sensor and the centerline average roughness is 0.90.

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This paper discusses uncertainty of estimates of contact conditions. The contact conditions mean contact position, contact force, and contact type between a robot and an external environment. It is important to evaluate the uncertainty, because sensing force and moment are contaminated with noise. This paper formulates least squares functions including contact position, direction of the normal, and direction of the contact line. The uncertainty is derived by using an amount of each function. The effectiveness of this method is verified by using numerical examples.

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The touch sensitivity increases temperarily when the proximal phalange of finger is pressed. While there are four kind of tactile receptors in finger tip, it is well known that each mechanoreceptor is activated with different frequency. By focusing on this fact, we can evaluate which receptor mainly contributes to improving the touch sensitivity by pressing. By observing frequency response of touch sensitivity, we found that it increases in the frequency range of 80 through 120 Hz under pressing. Also, we could observe that the tendency of sensitivity response with respect to time is quite similar to that of stiffness change of finger tip.

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Slip detecting tactile sensors are essential to achieving a human-like gripping motion with a robot hand. Up until now, we have developed flexible, thin and lightweight center of pressure (CoP) sensor. The sensor, constructed of pressure conductive rubber sandwiched between two sheets of conductive film, is able to detect the center position of the load distribution and the total load. Recently, detection of initial slip has been shown to be possible. However the detection principles are unclear. In this paper, we will discuss the slip detection principle of CoP sensor and the properties.

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A shape variation of an object is important information to achieve a dexterous manipulation by robotic hand. We consider that detection of the shape variation is possible through measurement of force vector distribution. Shape variation of an object causes spread of uniform force vectors.In order to measure force vector distribution, the robotic hand was instrumented with vision-based tactile sensor developed by us. Using the robot hand, we have examined the method that detects the shape variation using force vector distribution. As it follows from the experimental result, the robotic hand is capable to detect the shape variation of clay. Therefore, proposed approach could allow us to drastically improve the robotic hand manipulation.

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We proposed a stress tensor sensor that is embedded in an elastic body and can measure the stress tensor around it. The sensor consists of a cube shaped rigid body and sub-sensors that measure normal stress on each sides of the rigid body. We explained the theory to decompose the shear stress and the non-uniform normal stress. Also, we fabricated a prototype sensor. The theory was examined by the prototype. The experimental results show that the sensor can measure normal stress and shear stress at once. Also, the sensor can distinguish the shear stress and the linearly varied normal stress.

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We propose a method to detect the impact force which acts on a golf club head with strain sensors. This method is capable of measuring compression force and shear force and estimating the impact point. We made the large scale model for the impact measurement of a golf club and a ball. We also embedded in a golf club head two MEMS strain sensor units which size was 2 mm x 2 mm x 0.8 mm. This unit detected the strains of 10 kHz on impact in 0.4 ms. The result by the sensor was superior to that by a high speed camera in time resolution.

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The net structure proximity sensor capable of being attached to over robot entire body was developed. This sensor is effective as a sensor of the intermediate level of object detection. It is necessary to plan further high function to realize a robot by higher-speed exercise. This paper analyzes the effect of the sensor at far field.

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Previously active type surface acoustic wave (SAW) tactile display has been proposed. Using a square-shaped substrate, the SAW tactile display can be used to deal with two-degree-of-freedom motion. A pen tablet type interface using the tactile display is proposed. This paper focuses the feeling of drawing with a pen and introduces presentation of the feeling using the pen tablet type SAW tactile display installed on an LCD. Integration of the SAW tactile display and a visual display is described. The slider for generating vibration to present the feeling is installed on the nib of the pen. Measurement result of pen vibration during rubbing motion is also reported.

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The instrumented test system and the analysis for a novel tactile sensor are proposed to examine the material characteristic parameters on the basis of the indentation contact mechanics. A conjugate twin-strain-gage attached to the inner surface of a spherical glass-bowl-indenter senses in a differential manner the contact stress distribution beneath the indenter, and then allows to characterize the viscoelastic properties of the material indented. The indentation contact tests are conducted for polymer (polylactic acid, PLA) and candy (furan polymer) . The test results suggest the potential applications of this tactile sensor to the mechanical characterizations of viscoelastic materials as well as pure elastic and elastoplastic materials.

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The force sensor with AT-cut quartz crystal resonator has the characteristic that the resonant frequency changes by the external force, which achieves high sensitivity, high-speed response, and wide measurement range by a simple structure. Also it has the superior feature in the temperature and frequency stability. On the other hand, the quartz crystal resonator had been hardly applied to a dynamic force measurement because of low degree of mechanical characteristic, that is, it is weak to the impact, the bend, and tension. The objective of this study is to construct the sensor mechanism that safely maintains the quartz crystal resonator for the external force with flat structure. We designed and analyzed a novel retention mechanism of the quartz crystal resonator for the flat structure. The proposed force sensor is, small, sensitive, and robust from force in lateral direction, and it has wide measurement rage of 10^4. It can be applied to several usages such as medical treatment and dynamic contact force detection of human.

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Multi-axis force/moment sensor can measure force and moment is helpful for robotic force control. But the smallest multi-axis force/moment sensor has oversized height and worsens the stability of tasks. So it is expected to develop thin type multi-axis force/moment sensor enables robot hand to grasp object as if it were human. Therefore, we aim to develop thin type four-axis force/moment sensor can be mounted to finger cushion direction in this study. We obtained sufficient sensitivities concerning each axial direction as a result of sensitivity evaluation being based on finite element analysis and characteristic test applied determined positions putting strain gauges.

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This paper presents a hybrid tactile displaying method of realistic texture using ultrasonic vibrator and force display. The aim of this study is to display various realistic tactile senses by controlling multiple factors including roughness, softness and friction sense. First, a tactile displaying system was configured for displaying roughness, softness and friction sense simultaneously by compensating the interference among multiple parameters of ultrasonic vibration and force feedback on multiple tactile senses. Second, by conducting several sensory evaluation experiments, the relationship between each control parameter and the tactile senses were quantified. Finally, different from numbers of previous tactile displays, our tactile displaying system could successfully display various realistic tactile senses very close to the real texture of material surface.

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A new display method of friction sensation based on tactile stimulation is proposed. In this method, no tangential force on the fingertip is required to represent friction sensation. We focus on stick-slip phenomena when we rub on the surfaces and capture fingerprint in contact area. From the result, stick-slip frequency and appearance rate is different depend on finger velocity and normal contact force. The characteristic of stick-slip was expressed by a single DOF model with Coulomb's friction, which represents the effects of coefficients of dynamic/static friction and hand movements. The sensory magnitudes of the perceived friction by the proposed method were evaluated in contrast with a force display. The experimental results showed that the perceived friction proposed had high correlation with that of the force display in regard to the increase tendency toward static friction coefficients. The sensory magnitudes of the tactile perceived friction were about one-seventh smaller than that of the force display.

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This paper evaluates contact force variations on a sticky surface with respect to three different finger speeds. The measurements of fingertip behavior on a real sticky surface revealed that quicker pulling motion results in larger sticking force. The same measurement was done on our stickiness tactile display, which utilizes vacuum pressure to represent stickiness. The result of the measurement showed that the same tendency, quicker force results in larger force, appears on the tactile display.

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Soft stretchable sensor exterior has possibility to enable robots to conduct natural and safe behaviors using whole-body tactile sensing. Although some soft stretchable sensor using electro-conductive strings have been studied so far, knitted structures used in their studies are simple and limited one. Therefore, we tested more stretchable and sensitive sensor structure using electro-conductive yarn. Furthermore, band-type stretchable sensor exterior is prototyped and evaluated by putting it on an actual robot's arm.

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This report describes the fundamental study of recognition of vibration stimulation through tactile sensing by human fingers. When we feel stimulation of tactile sensing by a human finger, it dynamically swings to touch a surface of an object. Namely, relationship between the finger and the object is similar to stimulation of vibration. The tactile sensing is classified into several feeling patterns. Every feeling pattern is expressed by various words. To find out relationship between the feeling patterns and various vibration patterns, tactile sensing with the vibration is also classified into each feeling pattern by the extracted words in experiment in which a human feels the vibration patterns. A part of recognition of tactile sensing on vibration is shown by the experiment.

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The biometrics is important technology provide security and service for individual. In the biometrics, the identification employs gait is studied varied method. Because it has the advantage of the measurement is transparent. But, not only to identification, practical application of study employs gait measurement is difficult. Because gait measurement systems have problems on measurement area, expensive cost, complicated structures, and so on. We made a walking position sensor, flat, less number of wire and can be broadened, for wide range gait. And we can work out some gait analysis factors from this sensor output. And so we try to identification using these factors.

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The natural air weight flow supplied the capsule changed by us in proportion to sweat rate, and sweating total which constituted the servo system in which difference of air hygroscopic moisture and air hygroscopic moisture of the via capsule becomes fixed was developed.

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The form of the putt swing is different among person. This suggests that an advice that can effectively improve a person's skill may differ between them. This paper describes a method to classify putt swing form aiming to develop an advisory system. We obtained motion data of subjects using a motion capture system. The putt swing form was appropriately classified using cluster analysis.

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We propose a technique that automatically estimates a sports skill of examinees. In our study, we are discussing the technique for golf putting. However, we have estimated the skill only from apart of the examinee's motion data. It became the problem that the arbitrariness characteristics occur when choosing sensor. In this study, we introduce ensemble leaning to treat the whole motion data with Recurrent Neural Networks as temporary estimate sports skill and unify these result. The experimental result suggested the effectiveness of our method.

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It is generally thought that human beings have high-performance system in body movement. However, the mechanisms of body movement have not been clarified completely. It is believed that human beings unconsciously estimate the spatial depth from the two-dimensional figure projected on the retina to understand the three-dimensional space. This paper focuses on relations between human motion and vision in order to reveal mechanisms between human motion and cognition. In this study, we attempt to examine the effect of Miiller-Lyer illusion, which is a typical optical illusion, on human cognition and motion by using motion capture system. Based on the examination, this paper discusses an interaction between human motion and human cognition.

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This paper is concerned with the development of an ultrasonic wave sensor system. We propose a development of the sensor system for the robot moves in the parallel to the wall. Ultrasonic wave frequency is 40 kHz. The sensor output is calculated with a PIC (microcomputer), and it is displayed by a LCD screen. We propose the architecture to introduce made ultrasonic wave sensor system for moving environment. This architecture is simple, so it is applicable to measurement of the positioning control study.

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In late years the study that is going to realize human good movement to a robot by the development of the robot technology becomes popular, and the concrete application is enabled if we can analyze human movement mechanism. However, the movement generation mechanism is affected by various factors, and analysis / the consideration that considered all of them is difficult. Therefore at first, in this study, I paid my attention to connection of sight with the movement generation mechanism. How do acquire and handle given sight information? And what kind of influence does the sight information have on movement generation and the precision? I performed the orbit flattery experiment of the human being arms which I used an ocular movement experiment and a motion capture system for and tried analysis.

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In this paper, estimation system of physical constraint condition is proposed by using motion data during walking. The walking motion of subjects who weared braces on their bodies was analyzed and we found which parts in body are influenced by the physical constraint condition. By using HMM training of the motion data at the most characteristic body parts, the estimation system of physical constraint condition was developed.

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In this paper, we propose a new haptic presentation method for telexistence system that matches somatic sensation of the master with the position and posture of the slave robot arm. To realize this method, we employ a way that displays the torque on each arm joint of the slave robot to the operator's arm joints in order to match the proprioception of the slave arm with that of the user arm. According to our experimental result, our method does not require any agreement between the position and posture of slave robot's arm and those of the operator's arm, contrary to the conventional methods.

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We developed a system that estimates finger angle with a wearable device like a wrist watch. The device measures wrist contour shape changing with finger motion. Wrist contour sensing is realized by tiny photo-reflectors on the band of the device. The photo-reflectors measure distance between the band and the wrist surface. For switching the photo-reflectors, shift-register circuit is also implemented. Finger angle estimation consists of 4 steps; 1) aggregating wrist contour data of various finger motion in advance, 2) measuring wrist contour by the device, 3) selecting some similar wrist contour from the pre-measured data, 4) averaging finger angle of selected data. Moreover, contour data is corrected using particular finger motion for reduction of bad effect caused by difference of device attachment. In experiment, this system successfully estimated finger angle of finger flexion with wrist pronation.

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This paper discusses how object information gives an influence on the predicted handling force applied to the object. Object information includes a short-term memory and a prior-information, that is experience on handling a similar object and the observed visual information. We especially deal with a gripping-object motion, where the surface EMG (sEMG) signals are measured and the predicted handling force is estimated and defined using the integrated EMG (iEMG), that is integrated immediately prior to the gripping-motion. Experimental results show that the predicted gripping force is closely related to the short-term memory and a prior-information or knowledge of the object.

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The man-machine cooperative system is attracting great attention in many fields. Since a human skill is strongly affected by fatigue, the assist system must be designed so as to accommodate with the change of skill characteristics caused by fatigue. This paper presents a new fatigue recognizer based on the EMG signals and the stochastic switched ARX (SS-ARX) model. Since the SS-ARX model can represent complex dynamics which involves switching and stochastic variance, it is expected to show higher performance as the fatigue recognizer than using simple statistical characteristics of the EMG signal. The usefulness of the proposed strategy is demonstrated by applying to a peg-in-hole task.

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Human assist devices are expected to be developed in the field of welfare, home, factory and so on. The devices are required to not only to assist the human but also to be strictly stable. Impedance control based on position control is often used for the human assist devices because the control system is simpler than that of the devices based on force control. But if the impedance parameters are made to be smaller in order to get good maneuverability, the system becomes unstable because of the delay of the position control system especially when the assisted tools touch high stiffness environment such as a wall. In this paper, we propose an impedance control method based on position control by employing passive elements such as a mass, a spring and a damper. Then we show in a simulation that the system controlled by the proposed method with very low impedance parameters is stable even if the system touches a high stiffness environment.

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In this paper the robotic throwing task is taken up in order to achieve high-speed dynamic manipulation. We propose a kinetic chain approach for swing motion focused on the torque transmission. In addition the release method using robotic hand is analyzed for ball control. Experimental results are also shown in which a high-speed manipulator throws a ball toward the target.

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Deviance behaviors of driving from daily driving behaviors are one of factor of the traffic accident. Therefore, it will be possible to realize a safe-driving support by using a technique for judgment and classification of driving behavior considering with deviance.In this research, the methodology for the judgment and classification of deviant behavior has been proposed based on a definition for the daily behavior from driving behavior of driving. In this research, the statistical analysis for experimental data with subject drivers has been conducted. Especially, analysis for the similarity of driving trajectory at the turn left in an intersection has also conducted using correlation between driving behaviors. Moreover, to evaluate the validity of proposed analysis method, same analyses for the driving with time constrain which makes a stress for driving has examined. Finally, effectiveness of propose analysis for the turn left motion which focus on a compatibility using correlation analysis have been confirmed.

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Tactile sensation is perceived through deformation of the skin. Therefore, transmission of stimuli applied to the skin is an important factor for tactile perception. This paper presents the measurement of skin-transmitted vibration characteristics on human fingertip. Sinusoidal stimuli are applied on the finger pad and skin-transmitted lateral and longitudinal waves are measured by an audio cartridge placed at the skin surface of the fingertip. Measurements are conducted on a human finger, a human finger covered with collodion film, and water bed model of human finger. In addition, measurements are conducted on human fingers whose nails are bended. The results suggest that human fingertip has a resonance frequency among 200〜260 Hz on the skin-transmitted longitudinal waves and the characteristic is changed by bending the nail.

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