Essential safety is required in the place where humans and robots cooperate. To secure safety, it is one way to achieve that moving parts of those robots are lightweight and flexible. So far, bending type soft actuator by pleated plastic film has been developed. In this paper, we describe a development of a polypod mobile robot utilizing the plastic-film soft actuators as driving legs. It is expected some advantages which are the driving stability of irregular ground, the lightweight and portability of the robot. This paper indicates two points on the robot that design method of the legs and control method that the robot can realize forward and rotate movement verified experimentally.

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The paper presents force feedback compensation for joint torque control on P-E (pneumatic-electric) hybrid driven robots, whose joints are torque controlled by pneumatic artificial muscles (PAM) combined with electric servomotors in parallel. Although the delay in the pressure control loop can be reduced by the servomotors, torque error still remains due to the modeling error of PAM, miss-adjustment of wire tension, and so forth. To overcome the problem, we fabricated small inline force sensors to plug into PAMs. The method is evaluated by balance control on exoskeleton robot XoR2. By using the force feedback, the torque error was reduced, and the balance performance has been improved.

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In this paper, we propose a novel cycloidal speed reduction system. The system is consist of internal gear, cycloidal disk and rubber roller planetary gear inside the cycloidal disk. A motor shaft drives rubber roller directly by friction, and the roller turns around inside the cycloidal disk, pressing the disk to the internal gear. This roller turning is the eccentric input of cycloidal speed reducer. The feature of this reducer is quiet, high reduction ratio, small-size and low-cost. These features will help decreasing actuators' noise of entertainment robots and toy robots, which will improve pleasure of experience and qualities of speech recognition of the robots. The prototype of this speed reducer worked successfully, and noise was less than ordinal hobby servo motor.

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The aim of this study is to develop the measurement system to analyze the lumbar flection angle during nurse caring assistance motion. In this study, to analyze the burden on the waist of carers, we developed the analysis system to measure flection angles on the lumbar vertebra and sacral vertebra using light-weight and compact wireless motion sensors. The sensors are attached on the twelfth thoracic vertebra projection and the second sacral vertebra to measure these flection angles. The proposed system analyzes the relative angle of these flection angles and indicates an adequate working posture for a carer to prevent a low back pain. The experimental results show that the usefulness of the proposed system reducing the burden on the waist is revealed.

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The purpose of this study is to analyze effects on the insertion path of ultra-fine needle by pressing the ultrasonic probe. We developed a hypothesis that the insertion path is affected by the stress field and the insertion angle which occur with deformation of the issue. Then, to examine the degree of effect of each factor, we compared the deflection of the needle caused by the both of stress field and insertion angle with that caused by only insertion angle. As a result, it was revealed that insertion angle is a major cause of the change of the insertion path. Furthermore, it was shown that it is possible to reduce the change of insertion path by the guide to eliminate the insertion angle with deformation of the issue.

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Endoscopic operation using the surgical support robot can perform minimally invasive. But operator cannot obtain information of the power, because he does not touch directly the affected parts. So we have been developing a brain tumor removal robotic manipulator including a gripping force feedback system that provides the force detected by the sensor of the tip forceps to the operator. In this report, we investigate the performance of newly developed pulling force feedback device. New device consists of two parts. The first is the device which gives friction sensation on finger. The second is the device giving a sensation by feedbacking the force at wrist position of operators. We also performed sensibility evaluation by neuro surgeons and evaluated the validity of our system.

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This paper presents a new method of feature extraction and segmentation using near-infrared hyperspectral imaging camera. Hyperspectral imaging is a combination of digital imaging and spectroscopy. Hyperspectral imaging has been applied in the fields of remote sensing, agriculture, biological engineering and so on. The process of extracting effective information from the hyperspectral imaging data is required to automatic analysis method. In this paper, the hyperspectral imaging data segmentation method extracted the feature of the data based on principle component analysis (PCA) and K-means clustering are proposed. The proposed method is applied to the four evaluation experiment; (A) discrimination between fatty meat and lean meat, (B) discrimination between meat and flour, (C) classification of low oxygen environment and (D) classification of mouse organs. The results show the proposed method can select characteristic bands in the near-infrared range automatically. The proposed method is expected to be applied to other field.

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In this paper, we describe an algorithm for recognizing the surgical tasks conducted during robotic microsurgery, especially for suturing a micro-blood vessel. In the proposed method, the surgical tasks are recognized using a hybrid HMM/RF model. The motion of the robotic system during each surgical task is modeled using a random forest, and the transition between the surgical tasks is modeled using a hidden Markov model, which considers the minimum duration of each surgical task in the hybrid HMM/RF model. The proposed method was evaluated by recognizing 12 tasks during the suturing of an artificial blood vessel using the microsurgical robotic system, and the tasks were successfully recognized to have a 78.5% accuracy.

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Robot assisted surgery has become a popular procedure in American. However, gripping force is not measured and force feedback system has not been established. Therefore there is a need for sensors capable of measuring the gripping force. In this study, three axis load measurement sensor to be mounted on forceps tip was developed. From the simulation, the effect of the taper angle on the load measurements was revealed. Taper angle θ=π/4rad is the most suitable angle for measurement of normal and shearing load. As a result, measuring normal load applied to each zone, this sensor can calculate normal load and shearing load.

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In this study, we developed a method of real-time tracking of tissue contour with a relatively low exposure by use of Computed Tomography (CT) and Ultrasonic (US) Image. Even if it is difficult to extract tissue contour in US image, the proposed method made real-time tracking of tissue contour possible by complementary usage the contour information in CT image and the remaining motion information in US image. Specifically, the identified target contour information in CT image was traced onto the corresponding position in US image. The motion vector of the target tissue contours was estimated by speckle tracking of its surroundings. The target tissue contours in the CT image was animated by using the motion vector. The results of the evaluation test shown the possibility of real-time tissues tracking by the proposed method.

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We have proposed a palpation system utilizing haptic bidirectionality for laparoscopic surgery. Human can optimize exploratory movement according to tactile sensation. In this system, surgeons can feel output from a tactile sensor through a tactile display and haptic bidirectionality can be established. For this system, we have developed a forceps-type tactile sensor. The tactile sensor is very simple and has electrical safety for body tissue. It can be sterilized and be disposed because of its low cost. In this paper, we develop a tactile display that presents normal force to instep, where is in the unclean area of surgeons. The display does not have to possess applicability for sterilizing and cleaning. Then, the palpation system is assembled by using the tactile sensor and the tactile display. Moreover, an experiment is conducted and the result shows that the system has the availability for tumor detection.

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With the objective of developing a system for surgical scalpel cutting skill training, an experiment system, Bidirectional Force Measurement Haptic Recorder was built. Experiment was conducted with the purpose of quantifying the skill difference between the repetitions of trials and shapes of the blade. RT method was applied to evaluate the force and torque sensor data between the conditions. Results showed that difference can be noticeable at the beginning and the end of the round edge knife and throughout the sharp point knife. Certain interval period were found to have clear difference that may be used as discriminant feature for determining the skill. However, the pilot test was conducted on limited material and subject, and therefore, further tests are required to confirm the discussion on multiple condition and evaluated with skilled surgeons performance data.

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In the quantization of the liquid levels in the blood reservoir for automatically controlling the heart-lung machine, we considered sensing method from outside the blood reservoir with a force sensor. In this paper, we report on the real-time liquid level measurement using a force sensor. In addition, we propose a liquid volume estimation method from this digital input value.

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This study proposes a novel MR-powered robotic system controlled by the magnetic force generated from MRI scanner. In the proposed system, originally developed MR-powered actuator unit, which contains ferromagnetic particle as a power source, and spherical positioning mechanism are used. These elements benefit to develop a remote needle tip positioning system using the MRI scanner. The potential application of this system covers the automation for under MRI inspections, especially for the cryoablation of breast cancer. In this paper, we report on the performance evaluation of the MR-powered actuator unit and also suggest the spherical positioning mechanism which can be activated by the actuator units.

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Although radiofrequency catheter ablation (RFCA) is a minimally invasive treatment for restoring the heart rhythm to normal, it is difficult for surgeons to prevent puncture of heart tissue by the catheter tip. The purpose of this study was developing an active catheter for RFCA preventing tissues from puncture. This paper describes the results of the friction characteristics of inferior vena cava. The friction coefficient of inferior vena cava was related to normal force and slip speed. As normal force increased, static friction coefficient and dynamic friction coefficient was decreased. On the other hand, as slip speed increased, static friction coefficient and dynamic friction coefficient was also increased. Therefore, we found that consideration of the normal force and slip speed dependency was necessary for catheter control.

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We have developed a one part grasping forceps fabricated by Metal Injection Molding in order to realize low in cost, mass-produced and disposability. The new forceps is no assemblage and no risk of part decomposition. As the result of the verification experiment, the forceps operated opening and closing without plastic transformation.

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Tele-operated surgery has a great potential to improve the access to health care and the quality of the emergency medical care. However, the stability of bilateral control cannot be guaranteed due to the communication delay between the master site and the slave site. The study aim to develop a control scheme for ensuring the stability of tele-operated surgery. We propose a hybrid control of rate control and admittance control with an "Energy Monitor" which measures the energy flow between the master and slave sites. The system switches the control modes so that the system behaves within its stable region. The contact force is also limited according to the upper bounded energy. The proposed scheme was tested through simulations in a one degree-of-freedom setup. The results showed that the proposed system successfully controlled energy and contact force in a stable manner without an unfavorable behavior.

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Vein of the retina being closed is called retinal vein occlusion. As a new treatment for retinal vein occlusion, microcannulation has been used in eye surgery. Microcannulation is a treatment to approach the fundus by inserting a micropipette from the surface of the eye, injecting directly thrombolytic drugs to the retinal vein being occluded. Because microcannulation is very difficult surgery even for the experienced doctors, robotic system for vitretinal surgery has been developed. However, evaluation and training system is not well developed. Therefore, we propose the microvessel model with a circular cross-section and a curved surface structure for evaluation of some microsurgical robotic systems to assistant vitreoretinal surgery and training for doctors.

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People are limited to sit still or stay on bed for long period of time after a major surgery. Lack of movement may cause Deep-Vein Thrombosis (DVT) that can progress to Pulmonary Embolism (PE) which can result in death. Assistant robots have been developed to help patients with their lower limb movement. The first generation robot has simple function to force foot movement. However, there are also disadvantages to its weight and size. Second generation robot has been developed to be much more compact which has great advantage in accessibility for the users. In this study, the performance of the new robot is tested and analyzed.

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In vitreoretinal surgery, surgeons have to perform peeling of the internal limiting membrane (ILM) whose thickness is approximately 3μm. Precise motion is required in these this because the target tissue is very delicate, but the hand tremor degrades the motion accuracy of surgeons. Several eye surgical robotic systems have been proposed to assist surgeons in performing this difficult task, but the benefit of the robotic surgery has not been quantitatively evaluated. In this paper, we developed a sensorized eye model for a quantitative assessment of robotic eye surgery. The 3-axis force applied to the eye ground and the stress distribution of the eye ground can be measured with the proposed model. The experimental results show that the developed eye model has the capability for the quantitative assessment of the robotic eye surgery.

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This paper reports the temperature indicator for surgical simulator and temperature calculation method using image processing for visualization of temperature increase and distribution in the model. The indicator consists of polydimethylsiloxane (PDMS) and thermochromic pigment presenting non-reversible color change according to temperature increase. The indicator has transparency to observe the catheter inside the model during simulation. Temperature change of color indicator is calculated from the color change using several color space such as YCrCb and HSV color space. The range of the indicator is from 50 to 110 degree of C. The accuracy of the temperature measurement is approximately 2.0 degrees of C. Temperature distribution of ablated model was measured (Ablation temperature: 90 degree of C. Ablation duration: 10 seconds.). Finally, temperature change measurement of ablated tube-shape model was demonstrated.

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Currently, in the medical field, Surgeon instructs the irradiation point to other health care workers, and they change the irradiation location of non-shadow lamps in their hands. Also, during surgery, to illuminate the hand in a stable, Surgeon wearing the head lights illuminate the operative field by moving their head. However, the above-mentioned behavior in prolonged surgery leads to a decrease in efficiency and concentration Therefore, as one method of solving I'm developing a headlight system that can control the light irradiation location in a hands-free. The device is intended to support the operator in laparotomy Here. I report on system overview and the prototype small biaxial headlight mechanism

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Among various medical problems facing us in today's Japan are rapidly aging society, localization of medical doctors, concentrated visits of patients to large hospitals, etc. Development of diagnostic and treatment support systems is considered a solution to a pressing problem to help reduce loads on medical doctors. On other hand, actual diagnosis should be holding a Probe at same position for a long time. So, we have developed the ReDAT (Robotic-echography for Diagnostic and Treatment support system) to be able to diagnose by cooperative operation. This system realizes a coordinated motion according to the motion of the probe, which is held by the robot and is moved by a physician. The system recognizes when the physician grasps the ultrasound probe by 6-axis force sensor and touches it on body surface by processing echograms. As the results, this system has the potential to be able to support advanced diagnosis for conventional echography.

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In endoscopic laryngo-pharyngeal surgery (ELPS), surgeons use an arc-shaped forceps and tools to remove the affected portion by observing it with a flexible endoscope. Because the direction of the endoscopic view and that of the forceps handle are different, surgeons are required of high manipulation skills. To overcome this problem, we have proposed a 3-DOF mechanical motion converter, which converts the backward and forward input motion to the rotating motion about the arc center of the forceps. The experiment with the first prototype showed the enhancement of the controllability. However, the device is too large for installing in the operating workspace. In this paper, we developed a new motion converter taking account of the installable workspace in the operation.

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This Paper presents a novel evaluation method by measuring user's brain wave. In the experiment, we measured the user's brain wave when the user controlled the virtual arm with each easy and difficult position to control. As a result, the spectrum of the brain wave increased at easy position more than difficult position (t=1.681, df=7, p<0.1). We conclude that the brain wave changed as the user perceives that the virtual arm belongs to the user's body.

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This study proposes an MR image projection device for assisting incision-place marking task in neurosurgery. The proposed interface aims to enhance the neurosurgeon's spatial perception to assist understanding three-dimensional brain structure. It consists of an adjustable translucent screen with projected MR images, and a link arm with sensors to recognize the surgeon's embodied interaction. The proposed device provides haptic interactions that allow the surgeon to manipulate the depth information and spatial views of the three-dimensional brain structure on the basis of their embodied interaction. We conducted task load evaluation experiment and it is suggested that the physical and temporal demands are reduced by using our proposed device.

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I investigated the relationship between the layout of objects placed on a table and organizing the objects. In developing a system for tidying up tables through the cooperation between a robot and a human, it was necessary to identify table-tops that people consider to be untidy. Therefore, experiments were conducted in which participants were asked to evaluate the degree of order seen in images of tables that were presented to them. Participants were also asked to indicate the number of groups into which the objects on the table could be separated. The results indicated that objects organized into fewer groups were rated as tidier than objects organized into a more groups.

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In this paper, In this paper, we developed the new walker which enable person have hemiplegia to crutch walking training in hospital ward without monitoring. The hemiplegia patients need crutch walking training until leaving hospital. Though it is difficult to all patients train enough crutch walking because of limited rehabilitation time. Our walker has three advantages. First, it do not contact with the patients arm, leg and crutch when crutch-walking training. We designed the walker using the human body measurements database. Second, when patient falls, the brake will work automatically. Third, it follows a gait, without using a patient's hand. We investigated about safety of gait with walker.

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The aim of the study was to develop a motion analysis system to evaluate relations between the patella movements, activation muscles of the lower limb and pedal force during the pedaling motion. Four cyclists performed for 20 seconds at two pedaling rates (110-120 rpm and 80-90 rpm). The patella movements during the pedaling motion were measured using a camera motion capture system to track reflective markers. The value of surface electromyography (EMG) was measured by electrodes from the tensor of latae (TFL), vastus lateralis (VL), rectus femoris (RF), hamstrings (HAM) and gastrocnemius (GAS). Furthermore, the measurement of pedal force was conducted by a power meter (Pioneer Inc.). The developed analysis system, along with the measurements of the patella movement, EMG and pedal force, could evaluate the pedaling motion quantitatively.

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In order to reduce a road monitoring cost, we propose a system to monitor extensively road condition by cyclists with a smartphone. In this paper, we propose two methods towards road monitoring. First is to classify road signals to four road conditions. Second is to extract road signal from a smartphone's accelerometer in three positions: pants' side pocket, chest pocket and bag in a front basket. In pants' side pocket, road signal is extracted by Independent Component Analysis. In chest pocket and bag in a front basket, road signal is extracted by selecting 1-axis affected from gravitational acceleration. In the experiment of the classification method, overall accuracy was 75%. The experimental results of the extraction methods with correlation coefficient showed the overall accuracy were more than 0.7 in pants' side pocket and chest pocket, the overall accuracy was less than 0.3 in bag in a front basket.

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In the present study, we measured 3-axis force at other 3 points on studs of soccer shoes. To fabricate sensors with a diameter of 1 centimeter, we used MEMS (Micro Electric Mechanical System) 3-axis force sensor chips. These sensors made us possible to understand the force distribution when a soccer player performed the kicking. The force distribution was different from how the player approaches to the ball. At the first half of kicking motion, 3-axis forces were applied to outside and backward area of the sole affected the ball speed. The direction of shear force also influenced the ball kicking. We examined better movement of support leg for kicking a faster ball.

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Recently, minimally invasive surgery using surgical robot has been focused such as endoscopic surgery. However, there are some difficult cases that the surgical manipulator has reached operating field, further access to the deep intricate part or the back side of organ because the insert part of many surgical manipulator is linear shape. Therefore, it is considered that surgical manipulator tip itself is necessary to have both functions of expansion and flexion. Accordingly, it was focused that the muscle structure of elephant nose tip, as mechanism mimics which structure, the flexible manipulator with expansion and flexion functions has been developed. In this paper, it were described that the comparison between 3d motion analysis results of the mechanism and that calculated trajectory, and the operability.

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As a method for power supply, we proposed an active in vivo power generation system using an electrical muscle stimulation technology as an alternative to an implantation of batteries and a wireless power transmission. In this system, contractile force generated by applying electrical stimulation to skeletal muscle was used as an energy source. In this paper, based on the results of muscle contraction characteristics by electrical stimulation, an electromagnetic induction type power generation mechanism was designed and fabricated. The power generation performance of the proposed generator was evaluated using the gastrocnemius muscle of a toad and the net power generated in the experiment was 112μW.

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Recently, problems of low master of the techniques by students of Department of Dentistry and trainees due to decreasing numbers of patients and increasing numbers of dentists are raised. To address the problems a dental patient robot that operates in a similar manner to an actual patient was developed. At present, because the neck mechanism uses a gimbal mechanism, the range of motion for the vertical and horizontal directions is not sufficient. Therefore, it is necessary to carry out the development of new mechanisms and flexible multi-degree-of-freedom. Make new mechanism using a 3D printer. One hole in the center and three holes surrounding it were drilled. And it will drive in the rolling contact through the spring and wire. Also, the basic controlled to the basic one unit in this mechanism is calculated. I was possible to demonstrate the utility of the base unit.

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Recently, problems of low master of the techniques by students of Department of Dentistry and trainees due to decreasing numbers of patients and increasing numbers of dentists are raised. To address the problems a dental patient robot that operates in a similar manner to an actual patient was developed. The number of patients who fall ill during the treatment. Therefore, their knowledge is only knowledge acquired through books. They do not work through or they do not what to do when they see it. It is a study that develops a mechanism to reproduce the change of a body temperature and SpO2 of a patient during the treatment.

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In pharyngeal cancer surgery and single port surgery, arc-shaped forceps are used. Although some of them can rotate their tips in the axial direction, they have insufficient torsional rigidity because elastic inner pipes are used to transmit the torsional rotation. In this study, we propose a cracked metal pipe with ununiform intervals that can bend with a shape matching with an outer pipe still having sufficient torsional rigidity. We designed a cracked inner pipe by using computer simulation for a 5 mm diameter forceps. The contact force with an outer pipe is reduced, resulting in a small resistant torque caused by friction. We experimentally confirm that it can rotate with a torque of about 0.5 Nmm in the groove on an ABS plate.

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In this study, we develop the small device to induce motion illusion in ankle joint angle during a walk. We focused on deep sensibility which acts on sense of position and sense of movement in the sensors group. The motion illusion phenomenon induced by vibration stimulation with deep part mechanoreceptors such as muscle spindle and tendon spindle, and this phenomenon influences adjustment of the joint angle. The result of this study suggests that the vibration stimulus to tendon of the tibialis anterior muscle influences gait motion in patients with diabetic neuropathy.

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This study aims to develop comfortable and ergonomic pillows that accommodate to anatomical differences between individuals. This report describes our proposed method to measure the shape of the back of head and neck. This study improved the existing head shape measuring instrument. The new instrument enables to digitize the shape data of the back of head and neck. Relative positions between head and trunk were also measured from coordinates of four indicator points in picture, with several standing and supine postures. A difference is clearly found on the shape of the back of head and neck, and on the relative position between individuals. This result suggests that suitable pillow shape will change depending on the mechanical characteristics for each subject.

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Iaido is a modern Japanese martial art using Japanese sword. A player executes a sequence of actions: drawing the sword from scabbard, cutting a virtual opponent, removing blood from the blade, and sheathing the sword. Then multiple graders judge his/her mastery of skills subjectively. So, the judgment has possibility of including impropriety on validity and fairness. In order to tackle this problem, we propose an assessment function based on multiple regression analysis for evaluating mastery of iaido-skill from time series motion data. We measure iaido-action of three players by a motion capture system to get motion data. Then we investigate the validity of grader's judgment by comparing with a result of the assessment function.

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We focus on a time-series analysis method for swimming motion analysis based on the data form underwater wireless accelerometer. In this paper, we investigate the feature quantities that can distinguish swimming styles.

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We focus on a time-series analysis method for human motion analysis based on singular value decomposition of acceleration sensor data. In this paper, we investigate the characteristics of the analysis results obtained by a simple walking motion.

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Tibial stress fractures, which are among the most serious overuse injuries in runners, are related to lower extremity loading variables (i.e., vertical impact peak, average and instantaneous vertical loading rate). Although anthropometric variables are thought to be associated with the loading variables, evidence regarding the relationship has not been reported. The goal of this study was to predict the loading variables during running using anthropometric features. Ten male subjects were asked to run at 3.5 m/s on a treadmill mounted on force plates, where we calculated lower extremity loading variables. We also measured their anthropometric features mainly from lower extremities. There were no significant correlations between the anthropometric features and the average and instantaneous vertical loading rate. However, we found that vertical impact peak was predictable from the foot breadth normalized to the leg length, using both stepwise linear regression and multiple linear regression analysis. The results of the present study suggests that vertical impact peak was depends on anthropometric variables.

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We report the development of a tactile sensor for evaluation the tactile properties of biological soft tissues aiming at palpation of breast cancer, and low invasive endoscopic robotic applications. PVDF (Polyvinylidene difluoride) film and PSCR (pressure sensitive conductive rubber) are used as sensitive receptors in the sensor. The sensor is driven by a motor-crank mechanism to apply an oscillatory stress to the object to be evaluated. Both time-domain and frequency-domain parameters of the sensor output for the evaluation of the hardness and thickness of the object were discussed in the paper. The sensor system was further testified using a palpation model of breast cancer. Experiment results show that it is possible to discriminate pathological tissue from normal tissue using the sensor.

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Rubber Hand Illusion (RHI) is a phenomenon that a subject feels that a rubber hand (dummy hand) is their own when the rubber hand and the real hand are stroked synchronously and the subject receives the consistent sensory inputs between visual and tactile sensations. The consistent visuo-tactile sensation is a necessary condition for RHI, however we report that RHI can be induced by an asynchronous stimulations between visual and tactile sensations. In our experiments, the subject is required to cross their arms and given successive stimulations on their each hand. Our experiment is conducted in virtual environment. It is known that such stimulations cause the mis-temporal order judgment. Our results support that arm-crossing confuses the body image and the asynchronous stimulations can induce RHI.

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Flexible Sensor Tube (FST) means a system that comprises multi-jointed series of angle sensors. It can calculate all joints' coordinates from all angles, and so it can measure the shape of it. In this paper, we focus on the FST's feature and each parts' shape of the human body. And we propose the calculation algorithm of the human body posture. The method uses the FST joints' coordinates in the FST worn around the arms and principal component analysis. In addition, we designed and manufactured the system "FST-Helix" packaging the method, and confirm the measuring capability of inspecting. On the other hand, we experiment and measure the method with FST-Helix. As a result, we can calculate arm length from system data and detect the posture with comparative high reliability by the statistical process.

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In this paper, we propose a method, how to estimate the joint stiffness by using the posture of human body and surface EMG. In general, direct measurement of the joint stiffness is difficult due to the inner information. We used human posture and coarse quantization EMG information for estimation. As the result, the rough estimation of joint stiffness can be achieved by posture and strength of the surface EMG.

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In this paper, we describe an interface based on gazing direction without user's body restrictions. In our system, gazing horizontal directions were calculated by the relative position of a cornea with respect to the inner and outer corner of an eye. Also, gazing vertical directions were estimated by the curvature of Bezier curve that was used four points, namely, inner and outer corner of the eye, and two control points. In the test trial, it was found that the gazing directions was roughly estimated using the developed system.

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Driving assistant is very effective to reduce the traffic accident by warning driver and supporting his operation. In order to give accurate alarm and support, driver's status has to be measured correctly and speedily. In this research, we proposed a novel method to estimate the driving posture only from the pressure distribution between driver and car seat using a soft sensor sheet. Many pressure distributions for several driving postures were measured to create classifier using supervised machine learning method. The effectiveness of the generated classifier was verified using testing data and continued driving motion data.

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This paper deals with a new wireless bio-electrode using Bluetooth technology for human interface. This device is high performance wireless EMG measuring instrument with electric stimulation feedback function. And the electric stimulation is applied at the same point of EMG measurement. This device can be connected to various host devices by Bluetooth. The author develops usable interface easier than that is conventional ones.

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This paper describes an interface to operate the computer using hand trajectory. The skeleton information in humans of the Kinect sensor was used for detection of arm posture and hand positions. From the obtained information, the motion of the operator was recognized to reflect a mouse operation. In the mouse operations, the user could decide the position of the cursor with the right hand, and click with the left hand. In addition, we built the system which could choose two displays by changes in the depth position of the hand and the operability of the developed system was examined by the trial experiments.

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