This paper proposes a new manipulation method for environment control systems using a shape sensor for the physically disabled. This system enables a human operator to control various home electric appliances, and can assist the physically disabled in their daily activities. The operation method can be easily changed according to operator's ability. The operator can use not only haptic devices such as a keyboard, a mouse and a touchscreen, but also the bioelectric signals. In this paper, we propose a new manipulation method for environment control systems using a shape sensor that can measure a small curvature change. This paper shows the basic concept of the system design and the developed prototype system. The effectiveness of the developed system is verified through experiments by patients with a cervical spine injury.

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This paper reports the development of a power assisted suit system actuated by ultrasonic motors. The proposed assisted suit is designed to support a carer while performing nursing care works. Therefore, the structure of the assisted suit has to be designed to cover the carer's motion as far as possible and the suit are equipped with ultrasonic motors which are mounted in the parts closed to the joint rotation axis of elbow, shoulder, waist, and knee. Assisted suit's frame is designed as an exoskeleton structure which can protect the wearer from accepting the suit's own weight by contacting the foot part to the ground. The paper reports the φ 60 sandwich-type motor and the double sandwich-type motor for upper body part of the assisted suit as well. In addition, the torque of the double sandwich-type motor that combined two sandwich-type motors was about3. 8 times. From the above results, the double sandwich-type motor is less space-saving but it has high-efficiency of torque which is suitable as the actuator at the upper body of the assisted suit.

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We have developed a new hybrid magnetic(HM)bearing system for durable and small size artificial hearts. A prototype maglev pump was also developed to verify the feasibility of the developed HM bearing system. A small impeller centrifugal pump was combined with the HM bearing for the prototype pump. The impeller is levitated by a set of HM bearings at both sides of the impeller. A motor stator is set at the center of the device to rotate the levitated impeller. Maximum rotating speed with complete levitation in the air is15, 000rpm. Maximum oscillation amplitude in the radial direction is 0. 04mm with a target rotating number of5, 000rpm. The developed HM bearing system indicated sufficient levitation performance for the artificial heart and the magnetically levitated centrifugal pump with small impeller also displayed good pump performance as a ventricular assist system.

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The reduction of hydraulic force on a rotary VAD impeller is paramount for conserving power and minimizing impeller touchdown in systems employing magnetic suspension techniques. The objective of this research was to record the static hydraulic force experienced by a centrifugal LVAD impeller in a mock circulation loop reproducing various levels of heart failure. A closed type impeller exhibited a lower axial hydraulic force than a semi-open type at non-pulsatile design flow conditions of5L/min at100mmHg. A single volute demonstrated the lowest radial hydraulic force at these conditions followed by the double volute and circular volute. These forces were then found to fluctuate in the pulsatile environment, between values determined by non-pulsatile force results. The experimentally measured results aid the selection of a suitable impeller/volute configuration to minimize both impeller touchdown and power requirements of magnetic bearing systems in a pulsatile system.

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