We presented the method to guide and control a mobile robot under the environment informationized by IC tags since ROBOMEC2010. Our method is that the potential field is built in IC tags environment and the robot is led to the driving direction which is composition of the destination direction and the potential gradient vector written IC tags. This paper shows experimental results in the improved environment which reput IC tags on a 100mm interval and re-designed the potential field.

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This paper provides a study on a supporting system of choral singing for visually impaired persons. This system is composed of an electric music baton with an acceleration sensor, a radio module, haptic interface devices, KINECT sensor and a PC. An electric music baton transmits a conductor's motion to visually impaired players based on a signal of acceleration sensor. Since a conductor has to give individual instruction to a target player, we use a KINECT sensor in order to recognize the direction of a conductor's music baton. The direction of a conductor's music baton is estimated based on the positions of a conductor's both shoulders. The effectiveness of our system is clarified by several experimental results.

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This paper describes change in vibratory perception due to an adaptation, its modeling and correction method. Vibration alert interface is a vibration display device which conveys information such as distance and degree of risk using difference of vibration frequency and temporal pattern. In the vibration alert interface, user needs to perceive the vibratory frequency correctly, however vibration perception after the change was changed by the frequency before the change when the vibration frequency changes. To correct this change in vibratory perception, vibration perception model was constructed. It was able to correct the change in vibratory perception due to the adaptation using correction frequency calculated by proposed adaptation model.

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There is a great deal of research being done on exoskeletons and power assists. However, these technologies concentrate mainly on the amplifications of human muscle power while balance has to be provided by the human themself. This paper proposes an artificial balancer that supports human balance through acceleration of a flywheel attached to the body. Appropriate correcting torques are generated through our device based on the measurements of body deflections. We have carried out experiments with test persons standing on a platform subject to lateral perturbations. These experiments have demonstrated the effectiveness of our device in supporting balance and the possibility of enhancing balance-keeping capability in human beings through the application of external torque.

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We are developing the rehabilitation support system for repeated resistance training for severe hemiplegic stroke patients. We have developed a simplified repeated resistance training system equipped with a user interface for easy operation for a therapist. Moreover we have developed a brace for fixation as the attachment between the training system and the patient's arm. In this paper, we perform the functional evaluation of the simplified repeated resistance training system and the brace in the clinical site. Moreover we verify the rehabilitation effect of the repeated resistance training using the simplified system for a hemiplegic stroke patient.

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We have developed a walking support system controlled by powder brakes. The system has a treadmill and a patient support part. The treadmill has an endless belt controlled by a powder brake. The patient support part has a constant force spring and a powder brake. We have experimentally examined whether the patient support part is controlled by the brake as intended. However, we have never examined whether the treadmill is controlled as intended. In this paper, first, we describe the walking support system controlled by powder brakes. Second, we explain the treadmill and the patient support part. Finally, we experimentally examine whether the treadmill is controlled as intended.

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Students becoming a physical therapist (PT) or an occupational therapist (OT) cannot experience rehabilitation for actual patients' troubles before clinical training. For this reason we have developed Knee Joint Robot simulating patients' troubles for students to experience rehabilitation for patient's troubles virtually. The next step, we are developing a training program using the robot for the students to learn skilled manual training/testing techniques for patients' trouble. In this paper, we propose a training program consisting of the force display system, the monitoring system, the supervisory system and the evaluation system. We develop simulation algorithms of clonus occurring in testing or training. Moreover, we develop evaluation methods for passive movement during testing or training for a patient with knee joint contracture.

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We have developed a quantitative evaluation system on hand sensorimotor integration function. In rehabilitation, quantitative evaluation is needed for early recovery. The objective assessment of hand sensorimotor integration function should be necessary to evaluate how the affected thumb or fingers move smoothly. Our present study aims to construct the quantitative evaluation system of sensorimotor integration function of the hand finger. We hitherto have made a measuring device which reproduce softness and difficulty for grip as gripping a tofu. In this paper, we have evaluated motor skills of hands from grip force by grasping device which add weight as raised. The experimental results show the different tendency between non-dominant hand and dominant hand in the healthy persons.

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The purpose of this study is to establish a screening method of persons who have a possibility of falling accidents, and establish a training method to prevent falling accidents. We measured the changes of postural balance by using a gravicorder when the vibratory stimulations of 30, 60 or 200Hz are applied to paraspinal muscle or gastrocnemius muscle of healthy young males. When the vibratory stimulations of 30 or 60Hz are applied to gastrocnemius muscle, the COP (Center of Pressure)s shifted posteriorly. However, when applied 200Hz vibratory stimulations are applied to gastrocnemius muscle or 30, 60 or 200Hz vibratory stimulations to paraspinal muscle, the changes of postural balance were not observed.

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In this research, the luminescence block for the crosswalk entrance where the LED was buried under the road was developed. This luminescence block is the one setting it up on the attention rousing block edge at the crosswalk entrance. The detection time and the direction presentation performance at the crosswalk entrance by the presence of this luminescence block were evaluated by the testee experiment. For the low vision person, it can be said that a significant difference can be statistically confirmed, and the luminescence block is effective to the direction localization. Moreover, when they locate in the luminescence block, the location time can be located in a short time. However, it has been understood that the direction localization of the luminescence block has the direction localization accuracy same as the case where the direction is localized with the tactile walking surface indicator.

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We developed the visual impairment mimetic system to provide a visual impairment experiment system for visually non-handicapped person. Our system using AR technology with head mounted displays and buil-in stereo cameras. Captured images from the stereo cameras are processed in the PC to mimic a visual impairment and displayed on the head mounted display. In this study, we demonstrate the color-blindness experiment system as the one example of our system. Three types of color-blindness are mimicked, protanope, deuteranope and achromat. And we simulate several kind of color-blindness with slightly or severely.

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Gait rehabilitation is conducted using treadmills or parallel bars. However, there are reports of those who can walk in a training room of a medical facility but cannnot in other places. These are because real-life situations totally differ from gait situations in the training rooms in the presence of uneven ground and others cutting across in front of them, so gait rehabilitation is expected to be achieved based on daily living environments for each subject. In this paper, we suggest a walking rehabilitation system for every user.

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Balancing control capability is very important for people to conduct everyday life smoothly. This capability is classified into two types, static and dynamic, and we focus on the latter. In this study, we employed a measuring and training device for human balancing control capability. This device is constructed with a pair of parallel wheeled vehicles, and applies the inverted pendulum principle. There are three device types, which differ based on the subject's orientation to the direction of the wheels: 0, 45 or 90 degrees. We conducted a riding experiment combining those types, and examined whether the training effect for one type had generalization against the others.

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In this paper, we present and develop a gait training robot equipped with mechanical safety devices and torque limiters. The mechanical safety devices and torque limiters consist of only mechanical components without actuators, controllers and batteries. The mechanical safety device is attached to each drive-shaft of the robot. If the angular velocity of a drive-shaft exceeds a preset level, the corresponding mechanical safety device switches off all motors of the robot and locks the drive-shaft. The switch-off mechanisms using the torque limiters are mounted on the robot. If the torque acting on a drive-shaft exceeds a preset level, the switch-off mechanism switches off all motors of the robot. First, we describe the gait training robot. Second, we explain the mechanical safety device. Third, we explain the torque limiter and the switch-off mechanism using the torque limiter. Finally we experimentally examine the usefulness of the mechanical safety devices, the torque limiters and the switch-off mechanism.

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In this paper, we propose a method which controls lower limb muscles in quasi-static lower limb motion. We determined a quasi-static motion as a series of isometric motions. The method is added integrated muscle forces as a condition for the control than a previous method for isometric motion. The method makes muscles fulfilled the desired muscle force during the motion.

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In this research, we developed a novel ankle-foot assist device for rehabilitation and walking assistant purpose. Measurement and movement assistance of the ankle joint movement of 6 DOFs are possible for the developed assist device. A Stewart-Platform-Type Parallel Link Mechanisms is used, which can adapt to the displacement of the rotation axis of human foot. In this paper, we validate the static and dynamic motion measurement performance of the developed assist device. We conducted the static measurement performance verification experiment and the dynamic measurement performance verification experiment to validate performance of the developed assist device. Translation error measured by the developed assist device is less than 0.5 [mm], and rotation error measured by the developed assist device is than 0.6 [deg]. Dynamic motion measurement success rate that calculated by means of Cross correlation function is 0.99. The experimental results show the validity of the developed assist device.

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Patients with walking difficulties often rely on mobility aids for moving around by themselves. A Cycling Wheel Chair has been developed as an option in order to provide such patients an opportunity to fully utilize their bodies, including lower limbs and nerves. This paper presents the enhanced indoor safety concept, where the Cycling Wheel Chair warns the patient as he blindly approaches static objects, rather than completely taking over their controls. Also, quantitative evaluation of the driving ability with warning levels allows a patient to perform a rehabilitation exercise away from hospitals. The results of such evaluation can later be used by doctors for further driving ability assessments.

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A prototype pedaled wheelchair/ergometer system has been designed and developed for leg paralysis patients as part of the development of a rehabilitation system based on a brain-machine interface (BMI) for patient with motor paralysis. The wheelchair/ergometer system consists of a customized pedal driven wheelchair/ergometer and a BMI algorithm that detects the patient's intention. The patient's desire to move his (or her) legs is recognized from electroencephalography using current source density estimation and a support vector machine classifier. These recognition results are used for autonomous driving of the wheelchair/ergometer. The patient's feet are fixed to the pedals so that they move with the rotation of the wheels (pedals). Preliminary testing using this prototype system with an unimpaired subject showed that the discrimination accuracy between 'pedaling state' and 'resting state' was over 80% even in real-time operation.

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The voice made in vocal chords as a single sound source spreads radially when we speak. In addition, it is thought that the head itself plays the role of the special loudspeaker when the voice is emitted from the surface of it. Authors developed before the loudspeaker for robots with twelve dynamic loudspeakers embedded on each face of regular dodecahedron. The microphone unit to measure those performances was also developed. In this study, the performance tests of the microphone unit were done in the anechoic box.

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A new method of Human-Robot Interaction based on gesture recognition was proposed in this paper. Kinect sensor installed on the mobile robot was used for recognizing human gesture. Four types of gesture were prepared as user's command to operate a service robot which has capabilities of human following and autonomous navigation. Experiments were carried out to check the performance of recognizing human gesture and the possibility for robot operation.

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Recent advances in developing communication robots enable us to consider a bystander robot that supports human-human communication. Current paper proposes a framework for a bystander robot to select effective actions in order to enhance the synchrony between humans assuming that the interaction among humans and the robot can be modeled by partially observable Markov decision process. In the proposed framework, the future changes in human behavior according to the robot action are predicted and utilized to select the most effective action by the robot. In this study, we begin with examining whether the predictor of human behavior can be constructed by using the boosting algorithm on the sensory data observed from the experimental communication among two humans and a small humanoid robot. The experimental results of constructing predictors are reported and analyzed in terms of applicability for action selection by the robot to support human communications.

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We aim to develop an agent that performs natural dialogue with human using chatbot and to develop a system to estimate speaker's intention from dialogues. The dialogue system via chatbot is to select a speech sentence stochastically based on the dialogue log. In this research, we propose the mechanism of estimating speaker's intention using the feature amount based on words for developing system that performs dialogue entertaining speaker's intention. And, we perform experiment of estimation of intention.

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This paper proposed method of development for robot partner's gesture. First, we discuss necessity of multimodal communication for robot partner. Next, we focus gesture in multimodal communication and explain the gesture. Gesture is classified into 3 categories which is emblem, depicting gesture and deictic gesture. We used depicting gesture, and experimented in robot partner's impression with depicting gesuture. Finallry we discuss the result of experiment and evaluate the proposed method of development for robot partner's gesture.

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In this paper, we propose new rehabilitation system to target upper limb paralysis. This system is composed of EMG, AR, tactile stimuli. We take advantage of EMG at the site of paralysis as input of this system. And we conduct visual information presentation using AR, haptic stimuli presentation using vibration motor as output of this system. As a result of EMG, fingers of AR hand model bent at the same time. If the hand model grasps a virtual object, the patient feels the vibration stimuli. The patient has an illusion that the paralysis unit exercises in his own way.

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It is forecasted that by the year 2013, 25% of the people in Japan will be over the age of 65. An increase of elderly population having physical problems due to diseases and advanced age is considered to be a serious challenge. Therefore, rehabilitation training support systems are necessary and indispensable to accomplish sufficient rehabilitation. However, conventional systems are not widely used in the rehabilitation field because, they are too expensive and the system size is generally too large for installation. To solve these problems, we propose a new rehabilitation support system for upper limbs. Miniaturization and lowering of the cost will be achieved by using two-dimensional force display robots that are smaller than the conventional systems. We confirmed the first test model of the prototype two-dimensional force display robot for proposed rehabilitation system. And we verify the performance of the two-dimensional force display robot.

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In this study, a hand exoskeleton robot for rehabilitation using a three-layered sliding spring mechanism is presented. The advantage of the proposed mechanism compared to previously presented studies, is compact, light weight and high output force due to the compliant structure using the layered springs. In this paper, we introduce the mechanical structure of the proposed mechanism.

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This paper proposes a depression patient robot by using the android robot SAYA as a practical application of android robot technologies. The purpose of the patient robot is to offer reproducible and realistic education and training to psychiatrist trainees. In particular, the patient robot treats unipolar depression, which is a typical psychiatric disease. The robot exhibits symptoms of unipolar depression by exploiting its communicative functions such as facial expressions, eye and head movements, and distinctive speech. To evaluate its repeatability and educational effects, a field experiment was conducted in psychiatric education field.

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We are developing and researching on Ubiquitous Display (UD) that is a mobile robot composed of mobile platform and a projector with pan-tilt mechanism. UD provides visual information for people by projecting images in their sight. To achieve this purpose, human's position and direction are important information for UD. In this paper, we propose a method of estimating position and direction of human by using only a single Laser Range Finder (LRF). Furthermore, we verified usefulness of the estimation method for UD's projection through experiments.

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High dimensional input streams and unsupervised learning are two important factors in the area of humanoids and processes of the actions and movements of human. Our Fast Incremental Slow Feature Analysis (F-IncSFA) can learn and extract the few significant features of the complex sensory input sequences regarding high-level spatio-temporal conceptions. In this paper, the application of the F-IncSFA and some of its structure to make a hierarchical compound network made of F-IncSFA has been described. Also the techniques developed by adding efficient sparse coding as an encoder and a preprocessing step before an application of the F-IncSFA. The efficient sparse coding can dramatically reduces the dimension of extracted features and outcome of the efficient sparse coding are quite small as compared with the size of high-dimension video obtained by humanoid or human action. It has revealed excellent and promising dimension reduction by this preprocessor.

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This paper discusses the familiarity of a koala style robot. The familiarity is very important for communicating with robot to human. In this research, we are developing koala style robot by using various sensors to take various cute motions. The developed koala robot has 14 degree of freedom and has 7 different type sensors. We developed various motions to feel familiarity with koala robot. As an experiment, we have a questionnaire to evaluate the relation between familiarity emotions and motions of koala robot.

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This study proposes a novel control method that stabilizes a three-dimensional (3D) biped passive walker without knee and ankle joints by using frequency entrainment and a mechanical oscillator. Stabilizing method for a 3D biped passive walker using periodic input generated by Van der Pol equation was experimentally examined. The passive walker was stabilized on a downward slope and a flat floor by synchronizing the lateral motion to the sagittal motion. This research aims at improving the adaptability to the working environment by proposing the climbing control algorithm. It was analytically demonstrated that the novel control method using the change of the swing leg period stabilized a quasi passive walker on various upward slope. Finally, the validity of this control method is verified by experiments.

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This paper investigates the gait properties of passive dynamic walking of a combined rimless wheel (CRW) with a wobbling mass. We show that the walking speed increases by the effect of the wobbling mass and the gait efficiency changes with respect to the elasticity. We discuss the transition from inverse to normal phase synchronization from the frequency point of view. We then denote effect of initial angular velocity on the CRW gait and show a hysteresis phenomenon of in the walking speed. Furthermore, the validity of the simulation results is verified using an experimental CRW machine.

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The authors clarified that the measurable period of double-limb support (DLS) motion emerges in passive dynamic walking of a viscoelastic-legged rimless wheel (RW) through experiments and numerical simulations. This paper then defines the conditions for transition to DLS motion and discusses the potentiality for the emergence of DLS in limit cycle walking with knees. We numerically show that the measurable period of DLS emerges during the phase after impact where the knee joints are free.

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This paper investigates the adaptability of an active rimless wheel with an upper body and viscoelastic legs to flexible surfaces. The model achieves stable limit-cycle walking on level ground including measurable period of double-limb support only by stabilizing the upper body forward. First, we develop the mathematical model of flexible surface as a simple linear spring-damper system. Second, we numerically analyze the adaptability to flexible surface by comparing the steady walking speed with that of the rigid-legged model.

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The purpose of this research is to improve walking efficiency of biped walking robot. This research aims to make the biped walking robot considering the theory of passive walking. Biped walking robot that has two motors at the hip joint is developed. The controller for the robot is developed. The usefulness of the controller is confirmed by the experiment.

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This paper describe stability analysis of passive dynamic walking with ankles and toes. Human can walk effectively and stably. This is seems to be due to structure of human foot. Therefore, in this study, we built a passive dynamic walking model with ankles and toes like a form of human foot. We verified the stability analysis of the passive dynamic walking and effectiveness of ankle and toe in the proposed model. The method of stability analysis was performed using eigenvalues of the liner Poincare map. Effectiveness of ankles and toes were verified by using "Roll Over Shape". As a result, it is found that ankles and toes be effective in passive dynamic walking.

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We focus on communication from a smart electric wheelchair to the user to help the user understand surrounding environment. To realize this, we previously proposed a vibrotactile seat interface to provide environmental information to the user. Through experiments, we found several problems in interface use. This paper therefore presents improvement of the vibrotactile seat interface. We show experiments to confirm how users can detect activated motors correctly when using the proposed vibrotactile seat interface.

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In this study, we develop a robot system which can measure the amount of attention of the audience. The amount of attention is measured from the direction of the face and body of the audience. Direction of the face and body are detected by a distance information and image from the kinect sensor. The amount of attentions of the face and body is calculated respectively using Bayes' theorem. The amount of attention of the audience is calculated by the synthesis probability of the face and body.

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In the eye-gaze detection method using stereo-cameras, when a user wears eyeglasses, the glasses reflection of near-infrared LED light sources would be misdetected as the pupil. To improve the robustness of pupil detection, we propose novel pupil searching and tracking methods assuming that 3-D interpuillary distance is constant. The experimental results show the accuracy of pupil searching and tracking was improved compared to the conventional method.

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Passive dynamic bipedal walking (PDW) is an attractive topic not only for robotics field but also the other scientific field, i.e., physics and biology. However there are few researches on the measurement of 3-D PDW gait, which reveals its mechanism precisely. This paper describes how to measure zero moment point (ZMP) and posture of a 3-D PDW. A unique flexible displacement sensor and a usual 6 axes force sensor are utilized for the measurement. As a result, we found that ZMP trajectory draws '8' shape, which was similar to that of human. Moreover the measurement system clarified the relationship between walking gait and ballast position which is effective for stabilization.

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The purpose of the paper is to propose a design strategy of three dimensional passive dynamic walker made of cardboard for science and robot education. In order to introduce the walker as an educational program, a precise design method of the walker is proposed and is validated through some experiments.

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The objective of this research is to analyze humanoid's jumping and landing motions on a view point of arms' dynamical coupling for jumping. Humans use arms' swing to walk or run effectively and to jump highly by swinging arms up. Therefore, we deemed that humanoid robot can jump effectively by using dynamical coupling of arms. So, we focused on human's vertical jump, and gave input to arms in such a way as to swing arms similar to humans, and compared the jumping motion with arms' swinging motion and the ones without that. The results show what conditions causes the jumping be higher.

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Biped locomotion created by a controller based on ZMP known as reliable control method looks different from human's walking on the view point that ZMP-based walking does not include tipping-over state. However, the walking control that does not depend on ZMP is vulnerable to turnover. Therefore, we propose walking stabilizer based on visual feedback to enhance standing robustness and prevent the robot from falling down. Simulation results indicate that this stabilizer helps stabilize pose and bipedal walking even though ZMP is not kept inside convex hull of supporting area. Moreover, we point out that arms begin to swing asymmetrically by dynamical coupling among body links without input torques and verify the effects of the arms' swing on the walking.

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This research investigates a method to recognize people in indoor environment by using LRFs installed in the room and a mobile robot. Because of the time-delay in wireless communication and the position error of the robot, the information of both LRFs cannot be fused directory. Therefore, particle filtering and predetermined map were used to estimate robot position. Consequently, tracking information achieved from both sensors could be registrated correctly in the central computer.

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Human is thought to learn to extract image features as important cues for depth estimation in the developmental process. In this paper, we make a hypothesis that pictorial depth cues are acquired so that disparities can be predicted well and make a model that extracts features appropriate for depth estimation from static images. The experiments with simulation and real environments show high correlation between estimated and real disparities.

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This paper introduces a map management system in Town Management System (TMS), which is a data management system of a structured environment for a service robot. TMS has been being developed in "Robot Town Project" (NEXT) and "Intelligent RT Software Project" (METI/NEDO) for years as a key technology for managing a structured environment. TMS consists of a database for storing and extracting a variety of environmental information and a software library for data access. In this paper, we introduce some new functions which we appended to TMS to strengthen the map management function so that it processes metric and topological maps efficiently for a service robot.

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We propose a method for localizing furniture on caster and wheelchair using accelerometers and a floor sensor. The floor sensor measures positions of objects on the floor using laser range finder. However, it is difficult to specify each object since the floor sensor acquire only outline of the object. The accelerometer is attached to the moving furniture and integrated with the floor sensor for localizing and specifying it. In this paper, we extend our previous system for localizing multiple objects and verify effectiveness for a robot working in an everyday environment.

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This paper describes a method for location-estimation of mobile wireless LAN clients using strength of received signals from wireless LAN access points that are settled at various places in the multistoried buildings. A lot of training data that pertains between location of wireless LAN client and strength of received signals from wireless LAN access points at the location are needed to construct the location estimation system. We focus on the simplified measurement that the time interval for acquisition of strength of signals is shorter. We examine the location estimation under the condition that the measurement interval for strength of received signals for validation data is shorter; the interval is supposed to the real application. Experimental results show the feasibility of the short measurement interval for data acquisition.

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Aiming at the use in low-invasive medical treatments, a tungsten needle was fabricated by electrochemically etching a thin wire having 100 μm in diameter. Sharpness and smoothness of the tip are effective for easy insertion in the viewpoint of large stress concentration and small friction, respectively. An experiment of inserting the fabricated needle into an artificial skin of silicone rubber was carried out. The resistance force during insertion was much reduced due to its small size as mosquito's stinger. In spite of the ultra thin shape, the microneedle was neither buckled nor broken due to highly hardness of tungsten material. A hole was fabricated on the tungsten needle using excimer laser processing and electrochemical etching. Sampling water and blood was successfully achieved using this needle.

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Explicit finite element analysis (FEM) is applied to the analysis, in which microneedles imitating mosquito's proboscis are inserted to a viscoelastic material imitating human skin. The needles are central straight one imitating labrum, and side two needles imitating maxillas. The results obtained by simulation are as follows: 1) jagged shape of side needle is effective for reducing resistance force in forward motion due to decrease of contact area between needle and skin organism, 2) it has anchoring effect in backward motion, which eases the forward motion of central straight needle, 3) cooperative motion of these three needles makes the insertion force lower, which may be useful for low-invasive insertion of medical needle in future. A microneedle of bundling three needles is fabricated by MEMS technique, which imitates the shape and size of real mosquito. Using this bundled needle, the above-mentioned effect of cooperative three needles motion having phase to each other is experimentally confirmed.

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