We are developing a remote arm-wrestling system in which two persons at different places can do arm-wrestling fighting due to the exchange of physical information such as position and force. The purpose of this study is to prototype and examine a wrist device for our Cartesian coordinate type remote arm-wrestling system. Then, we made a wrist device based on the force detection device that we produced last year, and examined what kind of operation could be produced and whether the install of the wrist device to the remote arm-wrestling system influences the operation of the device or not. Moreover, we performed an experiment for measuring the driving range of the wrist device in order to actually use it for arm-wrestling fighting.

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In the entertainment robot field, it is important that the robot avoids collision along a smooth path when multiple robots corporately move. This paper discusses the motion path correction method using the Bezier curve with five nodes. In the design of robot motion path, the displacement of control nodes of the Bezier curve gives a simple correction method. As for the robot controller, robots are controlled to follow a virtual target that moves on the designed path. Considering the system by which multiple robots obtain position information from the image processing system and move on a designed path. Numerical simulation results are presented to illustrate the validity of the present correction method for some examples.

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A man-machine interface using EMG and EOG bio-potential signals for controlling one-axial positioning system is developed. Relationship between chewing force and EMG signal has linearity. EOG signal is in proportion to acceleration of eye movement. EMG signal is used for on-off switching and time integration of EOG signal with dead band is used for servo motor input signal. Experimental results of operation show that beginner is not easy to operate the one-axial positioning system with a servomotor. However, after training the operator can control the servomotor system by using the man-machine interface. This system is easy to extend more complex systems such as multi-degree of freedom robots.

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This paper proposes a simple and feasible method for a system that a Slave Robot can behave with biomechanical impedance, especially Joint Stiffness, of an operator obtained by measuring the operator's surface-Electromyography in Master-Slave System.

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In order to obtain high accuracy recognition of hand motions using surface electromyogram (SEMG), individual differences of SEMG are important issue. To solve this problem, we propose a channel selection method of the suitable measurement channels for the recognition of motions. We use a 96-channel matrix-type (6×16) surface electrode attached to the forearm in order to measure the SEMG generated from many active muscles during hand motions. From those 96 electrodes, our system decided the number of measurement channels and the position of measurement channels. This can be achieved by using the Monte Carlo method. Eignt normal subjects were experimentally tested using our system. We were able to distinguish all the motions (18 hand motions, including 10 finger movements), and the average recognition rate in the real-time experiment was measured to be greater than 95%. And the number of selected channels ranged from 4 to 7.

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This paper deals with the path planning of human digits in grasping a cylindrical object with the thumb and index finger. The trajectory of the thumb from initial position to the target could be divided into three patterns, a convex, double convexes, and non-convex type line. Moreover, the digit of thumb approached to the cylindrical object along to a tangential line will respect to the lateral of the object. Based on the obtained characteristics, the trajectory of thumb was approximated by the Bezier curve. As a result, it could be found that the distinctive patterns could be adequately expressed by the Three-order Bezier curve.

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A robot system cooperation with human instruction using finger movement is proposed in this research. A two-dimensional robot moves in cooperating with the motion of human finger which corresponds to the instruction by a human to move the robot in the system. By adopting this method, smooth movement trajectory of human finger can be reflected to the motion characteristics of the robot, which is acceptable to human psychology, and the motion trajectory of the robot can adjusted by the human arbitrary in real time. Four modes are considered to make this proposed system more practical one as follows. Mode 1 is implementation of cooperating movement, mode 2 is interrupt of the cooperating motion, mode 3 is adjustment of the gain between the movement of the finger and the movement of the robot, and mode 4 is initialization of the size of the gain.

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Though the perceived shift quality for a manual transmission is very important, a useful design framework of the operation feeling has never established. For the sake of simplicity and clarity as possible, we develop the shift operation system with a lock-ball mechanism. The dynamics of shift operation, which results from the interaction between human's arm and the shifter, is discussed. And, the shift operation simulator including a stretch reflex model is developed. Furthermore, we propose a unique approach that is the basic study including neuroscience for the haptic perception phenomena which are concerned with the shift feeling.

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In the vehicle system, a steering wheel is grabbed by driver with inevitability for one's driving operation. From the viewpoint of human interface designing, it is assumed that the steering wheel operation includes the driver's skills, intentions and psychological information etc. This matter has the possibility for realization of more suitable driver-vehicle interaction of intuitive driving. In this paper, the holding or grabbing styles of subject driver have been investigated through the experiments on a Driving simulator. And the relationship between the holding styles and the driver's situations has been discussed.

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When the human muscle is activated, we can observed a voltage called electromyogram (EMG). The EMG signal is expected to be used for the power assist system, motion estimation, and so on since it reflects human intention in the most direct manner. This paper presents a modeling strategy of the relation between human joint angle and the EMG. In particular, the relation between the wrist angle and the EMG of Extensor carpi radialis longus muscle is modeled based on the piecewise ARX model. By estimating the wrist angle using the identified model and observed EMG signal, the effectiveness of the proposed modeling strategy is verified.

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This paper presents the development and application of the decision making model in the driving behavior based on the logistic regression model. First, the decision making for the right-turn action in an intersection is expressed based on the logistic regression model. Second, it is shown that the model is applicable to the forecast of the decision making. Finally, two quantified measures "Decision entropy" and "Decision aggressiveness", that are expressed based on the estimated parameters in the logistic regression model, and proposed, and utilized for the classification of behaviors.

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It is generally thought that human beings have high-performance system in body movement. However, mechanisms of the body movement have not been clarified. In this paper, a kinematical model of a human upper limb is proposed to simulate of human upper limb, and a new technique of measurement is developed. Moreover, a motion capture system with this new technique of measurement is utilized in order to measure and analyze the motion cognition of human upper limb in velocity and manipulability. Finally, discussions of mechanisms between human motion and the human cognition are made.

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In this paper, we conducted psychophysical tests to investigate the effect of the directionality of human tactile sensation capability in discriminating fine step-heights. We evaluated the capability to discriminate the step-heights of 0-20 μm moving in the directions of 0,45 and 90 deg. The results show that the different directions of touching manner affect mechanism of human tactile sensation for recognizing surface textures.

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This paper demonstrates human weight perception for sudden weight changes during a lifting process. It is well known that human motion has an unimodal velocity profile including the acceleration and deceleration zones in a reaching task, which has a start and the goal points. This study attempts to reveal the difference of human weight perceptions between two zones by giving some magnitudes of weight changes with a force display device; especially, we investigate the difference threshold (DL: Differenz Limen) in the weight perception. The results show that human weigh perception tends to become more sensitive in the deceleration zone. Further, this paper shows the effectiveness of virtual reality technologies for physical experiments.

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Recently, advancement of virtual reality technologies can provide various force sensations to users. In addition to current visual and audio display technologies, it is expected that a force display would further expand application fields of multimedia services. This study develops two haptic interfaces with 3'DOF for force telecommunication that have an orthodox parallel linkage using two kinds of actuators, this paper details the fundamental property of these devices. Further, this paper tries to reveal the relationships between human sensations and system architecture such as servomechanism in order to realize force telecommunication with reality.

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For evaluation of rescue skill, or the early detection of the patient in a medical institution, quantification of pains is important. This paper describes techniques, which are purposed of evaluation of pains, based on human's feeling characteristics. The mechanism of a pain was investigated in order to attain quantification of pains. In the mechanism of pains, a receptor plays the role of a sensor. Accordingly, the neurotransmission model based on the characteristic of receptor is proposed.

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The purpose of this study is to develop a fatigue evaluation system for a task with high precision work. A situation where human engaging high precision task, for example, in a work of endoscopic surgery and assembling small instruments is increasing in these days. It is thought that people working in precision work suffer not only with physical fatigue but also physiological stress. So, we tried to develop the evaluation system which includes physiological indicators and motion coordination simultaneously for analyses of precise work. In the system, physiological tremor and ESAM (Emotion Spectrum Analysis Method) using EEG (ElectroEncephaloGraph) signals were measured to analyze the situation that human was exposed in an imitative endoscopic surgery. The task was to retain a stylus to objective position in 3-dementional space. The results showed that ESAM indicated stress signal when the stylus moved unexpectedly.

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We built an acoustical telepresence robot, Telehead, which has a user-like dummy head and is synchronized with the user's head movement in real time. We are trying to clarify the effects of reproducing head movement. In this paper, we evaluated the sense of incogruity induced by the delay time in reproducing head movement. The results indicate that head movement control should have a dead time shorter than 40 ms. They also suggest that the cue for the discrimination of delay is not the delay time itself. They suggest that subjects might discriminate the difference between the perception of auditory sound localization and somatosensory perception of their head posture.

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This paper describes the improvement of the maneuverability of a power assist device used in factories. An impedance control method based on force control is used in the device. Friction compensation can not applied in low velocity because the direction for the compensation is difficult to estimate in the velocity and the maneuverability becomes bad. Therefore, a technique in which the friction effect is reduced by mass effect is proposed for improving the maneuverability. If the mass of the power assist system becomes large, the friction effect is reduced but wasteful energy consumption becomes large. Then, an index evaluating both the reduction of friction effect and the energy consumption is applied to obtain an optimal mass and the effectiveness is shown by simulation and experiment.

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Diagnosis of anterior cruciate ligament (ACL) using body-mounted sensor is discussed. A wide variety of diagnosis method such as pivot shift test, lachman test and monitoring of jump motion are applied to examine the injured ACL. These methods, however, depend on the ability and the experience of examiner. The proposed method numerically provides the three dimensional translation and rotation of the knee by using a newly developed 3D sensor. The 3D sensor is composed of three accelerometers and three gyroscopes. Measured acceleration of the knee during the examination is converted to the fixed system of coordinate according the acceleration of gravity and 3D rotation of the sensor, and is numerically integrated to derive 3D trajectory and rotation angle around the tibia. The experimental results of jump test and pivot shift test show that the rotation angle of the tibia estimated from the 3D sensor provides unusual movement that suggests subluxation of injured ACL.

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The speed of recent robotic manipulation is very slow although a mechanical system excels in the speed of motion fundamentally. On the other hand various inventions which contribute to fast movement are reported in human motion. For instance, in human throwing motion we can observe the movement called "kinetic chain" which enables to propagate kinetic energy. Based on this motion, a throwing strategy focused on the superposition of wave patterns is proposed in order to achieve high-speed robot motion. The evaluation on contact modeling for control of a target is also analyzed.

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To make analysis of vibration for a parallel link robot caused by a low rigidity base plate, calculation of reaction force is one of the most important elements. This paper introduces a new calculation method of reaction force and dynamics for a parallel link robot and base frame system. Until now, calculation method for actuator torque from trajectory of end plate using virtual work principle has been well know. But it doesn't calculate reaction force which applied to a base frame. So, We propose a new method for calculation of reaction force using parallel link robot which is Malyland university type. This method is based on Newton-Euler method, principle of virtual work and D'Alembert. Calculated results are verified by an experimented results using three degrees of freedom (DoFs) parallel link robot which consists of base frame, end plate and three connecting legs each consists of one actuated joint and two passive joint. Also, We develop a 3D graphic simulator because it is necessary to visual confirm for motion and reaction of a parallel link robot.

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In this paper, we discuss about workspace of a 3-5R (three connecting chain, five revolute joints in each connecting chain) translational spatial parallel mechanism with consideration of singularity. At first, we derive the conditions of two singularities: actuation and constraint singularities. Secondly, we analyze the workspace of a mechanism with one type of connecting chain with consideration of singularity. In order to enlarge the area, which does not include any singularity in the workspace, ratio of link lengths and angle of adjacent revolute joints are investigated. Numerical examples are shown.

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This paper concerns the evaluation of kinematic and static characteristics of 3-URU-type pure rotational parallel mechanism. Its kinematic characteristics are represented by the relationship between the output velocity and input velocity. Static characteristics are represented by the relationships between output force and constraint force, and between output moment and input torque. Based on these relationships, we propose evaluation indices, each of which is nondimensional quantity. The effectiveness of these indices is numerically confirmed. We also propose an index to evaluate these three characteristics for a prescribed workspace. Finally we show an example of kinematic synthesis based on this index.

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We developed an artistic robot that is called "Jumping Joe." The robot has some special functions such as jumping and somersault. To achieve these special functions, the robot has the joint mechanisms that are employing parallel mechanisms with actuational redundancy. Those joints are employed as the hip joints. In this paper, we describe the structures of the hip joints, and the kinematic analyses of those mechanisms such as direct kinematics, inverse kinematics, singularity and static dynamics.

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This paper describes a method of measuring the plantar skin contact area and the plantar incipient partial slip in order to clarify the relation between a plantar tactile sensibility and a stabilization mechanism for a slip. The information of the plantar sense stimulus during walk had been not acquired in the conventional walk analysis. The meaning of plantar slip measurement is explained and the plantar skin deformation is measured by the image processing using the developed measurement device. An increase of plantar skin contact area by using ice immersion approach suggests the relation between plantar tactile stimulus and gait pattern.

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This paper proposes the design and development of the tactile sensor which can measure a 3-axis distributed force of a sole during a walk. The 3-axis distributed force wasn't noticed at conventional researches of walking analysis. The construct of the 3-axis distributed tactile sensor using silicone's rubber is reported. To measure the 3-axis distributed force, the sheet of silicone's rubber on which a number of circular truncated cone projections are putted designed and developed. The relation between the force and the deformation of a projection is verified with the developed sheet of silicone's rubber. Therefore, the 3-axis distributed force can be measured from the deformation of projections.

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This paper describes a luggable linear speaker arrays and a formation of sound spot. The existing linear speaker system array has already succeeded in forming a high sound pressure area in predetermined position. However, the existing speaker array system is heavy and hard to transport. The luggable linear speaker arrays are developed. The developed system can form a high sound pressure area in predetermined position.

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A sound spot which is a spot-like small area of high sound pressure level can be generated adding the delay of an appropriate amount to each output soud from many speakers. The columnar sound spot can be generated with two orthogonality axes speaker array (64 channel) and the spheroidal sound spot can be generated with three orthogonality axes speaker array (96 channel). The control of these two kinds of speaker arrays, 160 channel speaker array simultaneously, is achieved by plural computers synchronization. This paper reports on the generation of two kinds of sound spots simultaneously with 160 channel speaker array.

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Speaker array can from areas of higher sound pressure. We would like to explain of exhibitions by the speaker array system. The speaker array system needs external operability for exhibition support application. If we use the speaker array to explaining exhibition, the speaker array system is required to get information of object persons' positions for forming the higher sound pressure area at the positions. There are methods of getting information of object persons' positions by cameras and RFID. This paper presents a method of getting information of object persons' positions and controlling the speaker array system. The mat switches get the information of the positions by their own positions.

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This paper describes actual measurement on sound pressure propagation. We are studying speaker array which applies approach to hearing as a parts of robots to works on people. In order to examine the change of sound field forming by speaker array minutely, it is necessary that we measure dynamic characteristic of sound field. But, we could not measure to make sure of an effect of dynamic characteristic till now. In this study, it is the main object that we are enabled to measure the change of sound field from the dumb state to steady state in dozens of microsecond units.

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This paper describes the three-dimensional simulation and measurement of sound pressure distribution generated by 120ch plane speaker array and evaluates simulation. In the simulation, 120ch plane speaker array can generate a high sound pressure area, however such high sound pressure area is not measured. To actual measurement the three dimensional high sound pressure area, the simulation can be evaluated. The simulation is evaluated by using the coefficient of correlation. A value of the coefficient of correlation can calculate a similarity of simulation value and measurement value quantitatively. As a result, the effectiveness of simulation is confirmed.

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In this paper the authors propose 3 dimensional simulation of the speaker array considering reflection of a floor and an obstacle by FDTD (Finite difference time domain) method. Because it is necessary we set the condition that was suitable to simulate influence of the speaker array space. This paper describes changeable rate of sound absorption by combination of FDTD method and image source method and two new data about sound spot formed by speaker array. One is what kind of influence the sound spot formation by speaker array takes by reflection on a floor and, another is whether sound spot is formed when there was an obstacle in speaker array space.

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This paper proposes the parallel mechanism mobile robot whose body is a parallel mechanism. Its notable features are that the platform of its parallel mechanism body can be kept horizontal in rough terrain and that it can elevate another mobile robot to a high level to which the latter alone cannot ascend. We develop a four-DOF parallel mechanism mobile robot in particular. We experimentally verify that the robot can elevate another mobile robot of almost the same weight by making use of the kinematic singularity of the parallel mechanism.

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To introduce a passive complaint mechanism for robot joints is an effective way for impact absorption. However, because robots require high torque transmission, the simultaneous implementation of stiffness and softness is a significant issue. In this paper, we develop a torque transmission mechanism with passive variable stiffness that realizes from zero to extremely high stiffness using mechanical singularity. The analysis of zero stiffness and nonlinearity of the stiffness are established and the experimental evaluations are shown. The proposed mechanism is mounted on the knee joint and a four legs robot is designed.

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A robot arm has been widely used for various kinds of fields without remaining in industrial use. Versatility and flexibility is expected for the robot-arm to realize skillful operation in many fields. The purpose of this study was to propose the new mechanism of a small-sized 3-DOF effector with versatility and flexibility for multi-DOF robot-arm and to develop the robot-arm system that can realize skillful operation. The trial product was produced and the mathematical model was derived.

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We introduced shape warping approach to create subject-specific geometric model of human anatomy. Individual difference of shape is quantified as displacement field using volume registration technique against medical images of reference and target subjects. The manually created reference model was warped according to the computed displacement field to obtain geometric model of the target subject. This method was applied to geometric modeling of fingertip. The error between two models created by the presented method and the manual method was less than 0.1 mm in finger pad.

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In order to synthesize possible variations of fingertip, we analyzed individual differences in geometry of skin, distal phalanx and middle phalanx using principal component analysis. Volume registration technique was employed to quantify individual differences of fingertip from MR images of 50 male subjects. As a result of the analysis first, second and third components are turned out to correspond to difference in length, contortion and warpage of fingertip. Possible variations of fingertip was synthesized from these three components.

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To prevent child's injury, it is not enough to only offer information related to child's injury prevention. It is necessary to offer information and collect users' feedback data in parallel and offer personalized information based on collected data. As a concrete example of the system, we created a service which offers injury scene videos on the web. Through the service, we confirmed possibility of collecting users' feedback data. In this paper, we describe a method for selecting information which fits each user based on collected users' feedback data.

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One problem in modeling childhood injury in everyday life stems from that we use many kinds of expressions for the same thing. This terminology problem is common in science and technology of everyday life. To solve this problem, this paper describes a method for standardizing the expression of objects, injury mechanisms, injuries, features of objects and behaviors, and so forth based on the NOMESCO code system. This information standardization enables us to integrate a model of everyday life injury with an object database and a lifelog data in order to personalize information on injury prevention. This paper describes a method for visualizing risk of children's home injuries by information integration.

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Death due to drowning accounts for about 30% of unintentional injuries of 1 to 4 year-old infants in Japan. This paper describes two kinds of newly developed systems for preventing infants' drowning accident at home. One system is a sensor floor for detecting infant's "access" to bathroom. The other is a wave motion sensor system for detecting "injury occurrence" by monitoring unusual wave motion occurring immediately after drowning occurs. As for the sensor floor, the authors conducted experiments for 21 infants from 0 to 6 year-old. The success rate of detection is 99.2% for a target age group. A new finding related to infant's step is also described. As for the wave motion sensor system, fundamental performance of the system is reported.

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A wearable sensor technology enables us to conduct scientific research on our everyday lives by describing everyday phenomena quantitatively. For example, observing and understanding children's behavior in everyday lives is required for developing preventive measures of children's injuries. This paper describes a wireless wearable electromyography (EMG) sensor for measuring behavior of children in a daily living space. The system of a wireless wearable EMG sensor developed by the authors is presented. This paper proved the effectiveness of the developed system by conducting in situ measurement of 47 "playing" nursery school toddlers. This paper also presents the analysis of the play action data and its application.

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This paper proposes a bodygraphic information system that manages various information related to human body such as injuries by associating the information with human body geography. The concept of the system is similar to that of Geographic Information System (GIS). The system enables human-body-related information sharing in different fields such as medicine, engineering, and industry. This paper describes the prototype system. This paper also presents the feasibility and the significance of the proposed system by applysing the system to injury management in cooperation with a hospital. The authors collected, preserved, and visualized 169 injury data using the proposed system.

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This paper proposes a method for scheduling parallel forward dynamics simulation of complex human skeleton models. The method is applicable to several parallel algorithms such as Assembly-Disassembly Algorithm and Divide-and-Conquer Algorithm. These algorithms use the Inverse Articulated-Body Interia which can be computed by incrementally adding the joints. The scheduling method utilizes the fact that the joints can be added in any order, and applies A search algorithm to find the order that minimizes the computation time on given number of processors.

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While traditional method of estimating joiont model using thinning process of 3D shapes cannot deal sphere joint model, this paper shows a method of estimating sphere joint model by comparing 3D shapes of many frames with using texture data and technique of Reeb Graph. 3D shapes is calculated by markerless motion capture with using viewing field intersection method. This method don't need previous knowledge of joint structure. In addition, this method can create joint model of the subject which don't have any joint, for example soft-bodied creatures.

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An online approach is proposed to recover human body pose from 3D voxel data. The use of voxel data leads to viewpoint-free estimation, which benefits in that retraining is redundant in different multi-camera arrangements. Other advantages of our approach are speed and robustness. These are provided by an example-based method, applied by extracting posture labels from a large motion capture database. During the online process, only a similarity evaluation is needed between posture labels and online voxel data. The metric is formulated by introducing a histogram-based feature vector for representing the context of 3D volume. Estimation stability is improved by a precomputed graphical model of motion, which adds a smoothing effect to the motion sequence. We demonstrate speed and robustness of our approach with experiments on both synthetic and real image data.

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The purpose of this research is to help a technological improvement by measuring the movement data of the human body, and comparing an expert with an inexperienced person's movement. Solving optimization problems for higher-dimensional multi-body systems requires vast amount of calculation. Accordingly the expert's motion is assumed to be the optimal motion, and is compared with the beginner's motion. To make the beginner's motion approach to the expert's, the kinematical teaching elements are proposed. The kinematical teaching elements are defined as kinematical constraints for correcting the motion of human body. In this paper, the proposed kinematical teaching elements are examined.

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Human hand is one of the best manipulators existing now. So when we designing Robot hands, it is available that imitates Human's one. To that end we must understand Human hand construction in detail. So we made a "Dynamics simulator by the detail human model" that Musculotendon model based on real human, and locked at its behavior. In this way we are going to know characteristics and composition of Human hand. Heretofore in our research, we made a simulator that can actuate five-finger by that adds tension to the muscle and tendon. But sometimes it takes bad behavior, the finger strikes through the other one, the finger joint turns backward direction over 90-degree, etc. So for determining these problems, in this research, implements parallel spring elements for muscletendon And then the joints set up limit angle and joint damper.

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This paper is concerned with the development of the wearable sensor system for reading Braille. A compact wearable sensor using a PVDF (Polyvinylidene Fluoride) film is developed. The sensor output is measured with the sensor mounted onto a fingertip moving over Braille manually. A compact measurement, a robust recognition and a voice output part are also proposed. The wearable sensor system is fabricated by combining the sensor with these parts in order to teach the user the recognition results by real-time voice output. For the improvement of the performance, the classification is carried out using plural classifiers, each of which is based on multi-layer perceptions. The multi-layer perceptions are used in the form of dichotomizers, each solving a two-class classification problem. The sensor system is examined experimentally whether it is effective to recognize Braille. The obtained results show that the wearable sensor system is effective to recognize Braille.

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Easy human interface of an electric wheel chair was investigated to improve wheel chair maneuverability. The velocity control scheme of an electric wheel chair was proposed focusing on the operation speed of a joy stick. This paper will present the experimental results of the joy stick operation speed depending on LED lighting instruction.

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