In this paper, a muscle force estimation system using a motion analysis is proposed. Joint positions of the human body were measured using an image processing. Moreover, speed and acceleration of each parts were computed using a cubic spline interpolation method. Using results, the dynamic moment around a knee joint was computed and the muscle power estimation system of the M.quadriceps femoris when the knee joint extends was able to be built. Therefore, this measurement system was adapted to standing-sitting motion. As a result, the adaptability to the rehabilitation of a standing-sitting support system was confirmed for human who has lumbago.

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As one of the home services with a mobile manipulator system, we are aiming at the realization of the motion assist for older persons. The purpose of the work is to realize a safe assist by real time feedback control based on the information of sensor fusion from a three-dimensional camera for detecting the 3-dimensional coordinate and a high speed tactile sensor for detecting the load and its center. This paper introduces our basic method for assisting standing-up motion and system configuration, the design of tactile sensor as well as initial experimental results to show the feasibility of the proposed system.

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These days the aging society seems inevitable. It has brought many problems to our society because many elderly people have difficulties in spending an independent life. In this study, we have focused on human standing-up motion because it is the start point of many motions, and thus it is considered important. We analyzed relations among human joint torques, center of gravity, and muscles coordination. In this study, it was suggested that human standing-up motion can be divided into three phases based on muscles coordinated movements, and each phase has its own function: such as first phase indicates forward bending movement, next phase moves their upper-body upward, and the third phase controls their posture.

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In this paper, a standing - sitting support system is outlined and evaluations for the system is described. This system was developed for the elderly and people who temporarily have physical depressions. The system was evaluated using a questionnaire and moment around a lumbar and knees. The results of questionnaire demonstrated that 65 percent of subjects were able to feel the system's effectiveness. The estimated moment around the lumbar demonstrated that the system was able to diminish the moment in standing motions. As a result, it was found out that the standing - sitting support system can assist users' standing sitting motion sufficiently.

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The ambulatory measurement of ground reaction force (GRF) and human motion under free-living condition is really desired for gait analysis. A wearable force plate system was developed by integrating small triaxial force sensors and 3D orientation sensors for estimating triaxial GRF and orientations of the foot. As for the measurement accuracy, we compared the developed system's measurements of the triaxial GRF and the center of pressure (CoP) with reference measurements by a stationary force plate and an optical motion analysis system. The RMS difference of the two transverse components (x- and y- axes) and the vertical component (z-axis) of the GRF was 4.3±0.9N, 6.0±1.3N, and 12.1±1.1N respectively, corresponding to 5.1±1.1% and 6.5±1% of the maximum of each transverse component, and to 1.3±0.2% of the maximum vertical component of GRF. The RMS distance between the two systems' CoP trajectories was 3.2±0.8mm, corresponding to 1.2±0.3% of the length of the shoe.

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This paper describes construction of forward dynamical simulation considering foot segment deformation behavior. Foot segments, mechanical interface between external environment and body, are modeled as finite element model and other body segments are modeled as rigid link structure. Coupling these two models and solving equation of motion, body motion is generated. In order to validate the coupling method can represent foot-ground contact and stable standing position, simple simulation including non-contact and contact environment were conducted.

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Foot Orthoses (AFOs) are orthotic devices to support movements of ankles of disabled people, for example hemiplegia, polio, peroneal nerve palsy, etc. In our research, we have developed a passive controllable AFO (Intelligently Controllable Ankle Foot Orthosis) which can control its ankle torque by using a Compact Magneto-Rheological Fluid Brake (CMRFB). The brake has a simple structure and rapid response. Until now, we have developed three prototypes of i-AFO, but these are not enough for utilization in practical environment. In this paper, we describe newly developed i-AFO, 3rd prototype. In this device, we used accelerometer to detect contacts of a foot against ground. Additionally, velocity controller works in initial stance phase to maintain stable gaits even if the walking speed changes. We conducted validation test of new device and controller for a post-guillain barre syndrome patient.

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To apply the needs of medical & welfare fields, we developed omni-directional walking rehabilitation machine with lift type load support mechanism that support patient's body. The patient who has difficulty on independent walking and the aged can also use it. They can train even by themselves. And the load of staff's will decrease. Moreover, there are switches that detect the fall down of user, so the safety is more increased. We report about the hardware and the system configuration of this walking rehabilitation machine. Future tasks are to execute the operation test on the medical fields to obtain the evaluation and feedback.

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In this paper, a new type walk training Machine is proposed for the rehabilitation. This walk training Machine be called Seat-style Omni-Directional mobile Walker. This walker has following characteristics. (1) Severe patients who do not have standing muscular strength can use the walker. (2)This walker has the function of which the safety under training is guaranteed. (3)Because this walker can adjust to all the movements of walking, the best effect of training will be achieved. Finally, the these characteristics were verified by basic motion control experiment and Simulation.

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We developed the new concept walker (all-way mobile walker) and investigated the significance of its utility for the elderly. This walker has a small cell battery and 4 omni-wheels which are controlled by a computer. Accordingly the new concept walker (all-way mobile walker) can move unrestrinctedly under instruction of a computer. This walker can move latellary, posteriorly and obliquely. The improvement of muscle strength and balance function was shown after walking exercises by use of the all-way mobile walker. We expect this walker to contribute toward the fall prevention.

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Theoretical treatment has been carried out to elucidate the physicochemical characteristics of corona nano mist sauna generated by method of water fragmentation. The size distribution of corona nano mist is ranging from 20 to 50 nm and the number of minus ion is approximately 10,000/ml. The main results obtained for the study show that the oxygen minus ion attached water molecules, O_2^- (H_2O)_n, which is produced from corona nano mist sauna, has a significant effect for human body such as the recovery of fatigue and the purification of blood.

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In order to increase the productivity of a cell production system, assembly support in term of information plays an important role. However, large amount of information might cause high mental strain. For this reason, we had studied the relationship between information density and its induced effects on mental strain. In the experiments, from physiological parameter point of view, we had proven that the information density is proportional to the induced mental strain in information support.

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Acoustical environment inside various buildings should not to give stress to us. Loudspeakers have used for conveying information and flowing back ground music etc. usually. In this study, electrical actuator with high impedance for making sonic space that human can feel comfortable are developed and tried to apply them to glass walls or several types of walls in the building. Sound from this actuator has been inspected for effective to make healing space.

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The purpose of this research is to assist older persons confused in using information devices by giving appropriate guidance. In the previous report, we clarify the task completion times and vertical and horizontal scanpath lengths were found to be related to confused state. We proposed a recognition method of the confused state while using an information device. This paper proposes an information support system based on the confused state of elderly while using an information device. We found the validity of the proposed system by evaluating the gazing duration of the each target of the information device.

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Intelligent materials have been studying in various fields. In those studies, application study on biomaterials field and healthcare field attract particular attention. Intelligent materials are the materials with life form characteristics by themselves. In this study, Shape Memory Composite (SMC) is produced as one of those intelligent materials. SMC consists of Shape Memory Polymer (SMP) and Shape Memory Alloy (SMA). The SMA fiber is sandwiched in between SMP sheet. SMA's Young's modules get bigger when the temperature becomes higher than the phase transformation temperature. However SMP's Young's modules get higher when the temperature becomes lower then the glass transition temperature. Consequently, these two materials possess different characteristics in temperature changes. Therefore, we investigated the possibility on the SMC's actuator function as an intelligent material. The actuator function is achieved by applying to current the SMA fiber of SMC to catch and to release objects. As a result of this investigation, we would like to report as we found the meaningful data for actuator to design the SMC.

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This paper provides the evaluation of the ticket machine's display in consideration of the color universal design. Color universal design is an approach to the design of products and environments to be usable by visual disabilities, including persons with color blindness. We determine the color arrangement of the ticket machine's display by means of the result of the eye tracking.

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Nowadays, the epidemic of lifestyle-related disease is a serious social issue in the world. To prevent those diseases, we propose a surrounding healthcare environment where the users without strong awareness of their healthcare can improve their lifestyles naturally. In the proposed environment, our system detects healthcare contexts representing the opportunities to build up users' health in their daily life, and assists the users in being aware of the healthcare contexts by surrounding ICT devices naturally. In order to provide timely assistances to the users in daily life, the system has to recognize present situation related to the users' healthcare. In this paper, we discuss what kinds of healthcare situations, such as location or action of the user, should be detected for suitable assistances and then we propose the formal description of various daily healthcare situations, based on the state machine diagram of the unified modeling language (UML).

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Recently, accidents such that seniors fall down from the bed in care facilities or hospitals are increased. To prevent these accidents, we have developed an awakening detection system using Neural Network (NN). In this paper, to confirm the detection capability of the awakening detection system in the clinical site, it is conducted that the detection experiment using the captured image in the clinical site for the detection. From the result of this experiment, the detection success rate of this experiment is low. So, we analyze the captured image in the clinical site. From the result of the histogram analysis, it proves that the fluctuation of brightness quantity makes decrease the detection capability. Therefore, to decrease the influence of the brightness quantity, the histogram of the captured image is equalized. Finally, it is verified that the histogram equalization reduce the effect of fluctuation of brightness quantity

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Recently, touch panel has been in widespread use as interface with high usability. However, it is necessary to establish evaluation method of usability of the touch panel. In this study, it was conducted one experiment for evaluating usability of touch panel by use of arm manipulability and for evaluating relationship between installation position of touch panel and usability. We asked examinee to operate on touch panel in seven panel angle conditions (0, 15, 30, 45, 60, 75, 90 degrees). As evaluation index, we used switch operational frequency, torque of each joint, arm manipulability and compare the result of them. From the results, it was showed that torque of each joint correlates with switch operational frequency. It was found that we may be capable of applying to use arm manipulability as touch panel evaluation index.

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As the computer and internet generations age there is an increasing need to develop appropriate interfaces for the elderly that can accommodate age-related changes in manual dexterity, visual acuity, and cognitive abilities. Assessment of age-related effects is typically a necessary first step in designing age-appropriate interfaces, but may be complicated in how the tradeoff between speed and accuracy is handled by different people. In order to assess the impact of a possible speed-accuracy tradeoff, performance was observed under three different instructional sets i.e., accuracy (A), neutral (N), and speed (S) when steering on a circular track. The elderly group performed significantly less accurately for all three instruction sets. The younger subjects were more influenced by instructions to perform faster, or with more accuracy. Implications for user interface design for older users, and for the evaluation of age effects in HCI generally, are discussed.

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We have been working on a project on "Development of the drive dozing prevention technique using the sensor installed in the seat for detecting the driver's condition" for about five years. As a non-invasive sensor equipped with a drivers' seat for passenger cars, we developed so called "air pack sensor" which is expected to an alternative of finger plethysmogram. In the previous paper, mathematical modeling for air pack sensor was conducted and the method for extracting the heart rate signal from the signal obtained by the air pack sensor was proposed. In this paper, we mainly investigated the relation between the effect of the sensor position and the accuracy.

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A typical method for measuring the load added to the intervertebral disk that causes lumbago is an invasive method to inserting the electrode into there directly. In this study, the intervertebral disk load is estimated by noninvasive method of measuring the shape of spine with three dimensional motion analysis system and signal processing. Under assumption that spine is a beam, spine is approximated in the curve with theory of beam, and the load is evaluated by using the amount of derived curvature change. Therefore, proposal method is safe. Moreover, intervertebral disk load can be estimated while moving.

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Estimation of person's joint moment is very important in the field of the medical treatment and sports. In order to calculate a person's joint moment using inverse dynamics, data of the mass and the center of gravity of each part of the human body are necessary. However, in the present state of affairs, general statistical data are used and it causes low precision of the estimation because the subject's data are not used. In this study, we develop a new method to identify the mass and center of gravity of each part of the subject. Multiple regression analysis is carried out using 3-dimentional coordinates of the parts of the subjects and the floor reaction force. To estimate the accuracy of the proposed method we carry out numerical simulation and demonstrate the calculation results of the simulation.

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The theoretical treatment has been carried out to elucidate the physic-chemical characteristics of the electro-magnetic waves and the electric charged particles emitted from the polar crystal materials, that is, Tourmalines. The characteristics of the electric-magnetic waves evolved from such crystal materials belong to the mode of molecular vibration, that is, belong to the regime of far infrared rays, and the range of the wavelength and spectral emissivity are 4 to 16 μm and 0.92 in average, respectively. Additionally, we may predict that the Tourmaline powder mixed the excited materials makes it possible to emit the electric charged particles and we may also suggest that such process may have the possibility to produce the oxygen minus ion (O_2^-).

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An innovative training machine has been developed to improve or maintain elderly people's body strength. Resistance force to be loaded on user's body is generated by an electric motor and dynamically controlled during the exercise based on the level of user's muscle activity. One feature of this training machine is a function to automatically limit the maximum muscle activity to a prespecified level during the exercise. It is expected that this feature is very effective to increase safety of elderly training. The other feature is a function to dynamically control resistance force so that the level of user's muscle activity follows a prespecified curve from the beginning to the end of each cycle of the exercise. This feature provides more efficient and effective muscle strengthening to users compared with conventional training machine. The detail and experimental results are reported in this paper.

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In this paper, the affinity of the two-wheeled inverted pendulum vehicle with pedestrians is evaluated using KeyGraph. The psychological component factors of pedestrians are investigated on the vehicle and the other personal mobility. The uncomfortable and fearful situations are interpreted through the KeyGraph and their causes of mobility are shown. The results indicate that the physical features of the vehicles such as size and weight are the general factors that give psychological impact. It is also shown that the unfamiliarity of the two-wheeled inverted pendulum vehicle or the particular meaning of the vehicle, such as a wheelchair and a baby carriage which are welfare-purpose vehicle, can be the important factors that effect psychology.

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An master-slave control method for an upper limb rehabilitation robot system which can afford training for hemiplegic patients is introduced. The system consists of two identical motors with the master motor working in the generating state and the slave motor working in the electro motion state. Based on hemi-disabled characteristic of hemiplegic patients, the healthy limb is used to operate the master motor to generate electric energy, which in turn powers the slave motor to rotate and support impaired limb in motion imitation, thus realizing rehabilitation training. An experimental prototype with energy supplement control was developed. The appropriate amount of energy is compensated to the master- slave closed-loop circuit to compensate the inside energy loss, and further to achieve good speed tracking performance. Test experiments were conducted and the results confirm that the proposed system is capable of achieving energy recycling, motion tracking, and force sensing without a force sensor, thus has a great potential for application in rehabilitation robot systems.

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Silver car is a handcart for old people. It is very popular when they take a walk. The structure is very simple and it has many functions However, in country side such as Koichi, there are many unpaved roads. On such a road, to use a silver car may be patient for old people because of vibration of a handle bar. In this paper, a consideration of comfortable use of the silver car is discussed. Suspension mechanism installed on the silver car is examined. Suspension mechanism is introduced and some experimental results are shown.

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Muscular moment arm length (MMAL) is a basic physiological parameter to analyze musculoskeletal mechanism of leg. However, how to appropriately estimate personalized MMALs in vivo is controversial question for a long time. In the study, the estimating processes of individual MMALs of leg are demonstrated by mean of an anthropometric method. Firstly, skeletal morphological parameters of leg are obtained by measuring individual skeletal characters on leg's surface. Then, the skeletal morphological parameters are inputted into a series of regression equations for calculation of muscular origin-insertion coordinates in musculoskeletal coordinates of leg. Finally, MMALs of leg are estimated by inputting the measured physiological parameters and motion data of leg's joints to an algorithm. The experimental results suggested that the method is feasible to estimate personalized MMAL in vivo for leg's musculoskeletal model analysis.

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This paper introduces a cooperative control algorithm that designs a stable biped walk satisfying a wearer's intention relating to his/her walk such as a timing to start and stop walking, walking speed and waking direction so on, so that an exoskeletal walking support system could provide a comfortable support to a paraplegia patient. At first, a pair of gloves with several DOFs is developed to convey a wearer's intention to the walking support system. He/she swings both his/her index fingers to simulate foot motions of his/her walking. The amplitude of the swing corresponds to a step length of the walk and pronation/supination of the wrist joint of his/her right arm corresponds to a walk direction. The cooperative control algorithm based on a cart-table model designs trajectories of each joint for stable walking pattern that satisfies the intention expressed by the wearer's hand motion and then the designed walking pattern is executed in realtime by the walking support system. As the first trial, a small humanoid robot "HRP-2m" is used for safety as a control target that will be a combination of a wearer and the walking support system in the final situation. Through some experiments we confirm that our proposed algorithm enables the humanoid robot to start and stop stable walk with variable step length in the desired walking direction according to operator's intentions.

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