The measurement method of three-dimensional posture and flying trajectory of lower body during jumping motion using body-mounted wireless inertial measurement units (WIMU) is introduced. The WIMU is composed of three-dimensional (3D) accelerometer and gyroscope of two kinds with different dynamic range and one 3D geomagnetic sensor to adapt to quick movement. Three WIMUs are mounted under the chest, right thigh and right shank. Thin film pressure sensors are connected to the shank WIMU and are installed under right heel and tiptoe to distinguish the state of the body motion between grounding and jumping. Initial and final postures of trunk, thigh and shank at standing-still are obtained using gravitational acceleration and geomagnetism. The posture of body is determined using the 3D direction of each segment updated by the numerical integration of angular velocity. Flying motion is detected from pressure sensors and 3D flying trajectory is derived by the double integration of trunk acceleration applying the 3D velocity of trunk at takeoff. Standing long jump experiments are performed and experimental results show that the joint angle and flying trajectory agree with the actual motion measured by the optical motion capture system.

Measurement of physical activity is one of the key subjects in the field of ambulatory cardiovascular monitoring using such as Holter ECG and so called "ambulatory blood pressure monitor (ABPM)". Rehabilitation and gerontology will also be another fields for the application of the activity monitor. From this point of view, we have developed a portable device for monitoring human posture and walking velocity in ambulatory subjects. In this paper are described, a new sensor system for this purpose using three accelerometers and one gyroscope, its availability for the accurate measurement of human posture and walking velocity, and results of preliminary study using a prototype system for ambulatory monitoring.

To evaluate the effectiveness of rehabilitation, physical therapists must assess the posture changes in patients standing-up, walking, etc. Conventional subjective assessment of using direct observation or interviews at rehabilitation centers and of the actual physical condition is difficult, calling for the development of objective measurement of the posture change and activity both at rehabilitation centers, and in the home. One way to do so is to record these using a video camera, but the measurement range is usually limited and not useful in rehabilitation. A wearable system for monitoring angle changes in the trunk, thigh, and calf on the sagittal plane together with walking speed we developed earlier, required that the user carry three sensors for the trunk, thigh, and calf and a data logger, and wear cumbersome cables. To eliminate this practical drawback, we designed a new sensor for rehabilitation and quantitatively assessed posture change during rehabilitation and activity in daily living using the new system. We combined the previous four units into two – a jacket-typed trunk unit holding a data logger and a sensor for measuring trunk angle change and a knee-supporter-typed lower limb sensors containing two angular sensors – greatly simplifying the cumbersome cable assembly. We measured activity in eight rehabilitation subjects and four subjects during daily living using the wearable device. Results demonstrated that our device could measured detailed motion characteristics as angle changes between body segments during rehabilitation, and the rate of four activities – standing, walking, sitting, and lying – during daily living, making it useful in rehabilitation.

Abstract-Daily monitoring of health condition is important for an effective scheme for early diagnosis, treatment and prevention of lifestyle-related diseases such as adiposis, diabetes, cardiovascular diseases and other diseases. Commercially available devices for health care monitoring at home are cumbersome in terms of self-attachment of biological sensors and self-operation of the devices. From this viewpoint, we have been developing a non-conscious physiological monitor installed in a bath, a lavatory, and a bed for home health care and evaluated its measurement accuracy by simultaneous recordings of a biological sensors directly attached to the body surface. In order to investigate its applicability to health condition monitoring, we have further developed a new monitoring system which can automatically monitor and store the health condition data. In this study, by evaluation on 3 patients with cardiac infarct or sleep apnea syndrome, patients' health condition such as body and excretion weight in the toilet and apnea and hypopnea during sleeping were successfully monitored, indicating that the system appears useful for monitoring the health condition during daily living.

Abstract-The demand for ubiquitous healthcare monitoring has been increasingly raised for prevention of lifestyle-related diseases, acute life support or chronic therapies for inpatients and/or outpatients having chronic disorder and home medical care. From these view points, we developed a non-conscious healthcare monitoring system without any attachment of biological sensors and operations of devices, and an ambulatory postural changes and activities monitoring system. Furthermore in this study, in order to investigate those applicability to the ubiquitous healthcare monitoring, we have developed a new healthcare monitoring system combined with the non-conscious and the ambulatory measurements developed by us. In patients with chronic cardiovascular disease or stroke, the daily health conditions such as pulse, respiration, activities and so on, could be continuously measured in the hospital, the rehabilitation room and subject's own home, using the present system. The results demonstrated that the system appears useful for the ubiquitous healthcare monitoring not only at medical facility, but also during daily living at home.

The importance of human posture monitoring is well recognized in the field of rehabilitation, in order to evaluate quantitatively the effectiveness of rehabilitation by a physical therapist. The activity monitoring is also well recognized as being useful in the field of certification of eligibility for long-term care. Assessment of the actual physical condition of the applicant tends to be difficult when determine the level of need for long-term care. Taking these circumstances in consideration, we attempted to measure the activities of patients in rehabilitation using a wearable device for monitoring human activity. The results clearly demonstrated that detailed motion characteristics could be detected during standing up, walking and sitting up as angle changes between specific body segments and as trunk motion acceleration.

Daily monitoring of health condition at home is very important not only as an effective scheme for early diagnosis and treatment of cardiovascular and other diseases, but also for prevention and control of such diseases. From this point of view, we have developed a prototype room for fully automated monitoring of various vital signs. From the results of preliminary experiments using this room, it was confirmed that (1) ECG and respiration during bathing, (2) excretion weight and blood pressure, and (3) respiration and cardiac beat during sleep could be monitored with reasonable accuracy by the sensor system installed in bathtub, toilet and bed, respectively.

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