Yasuyoshi Asai

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This paper proposes a feedback control method for a linear resonant actuator (LRA), in which an external load estimated from two signals of the back-EMF is used as a target voltage in PID control. From the estimated load, it becomes possible to obtain an arbitrary amplitude of the mover. The effectiveness of this method was verified through FEM analysis.
This paper proposes the dynamic analysis method of a linear resonance actuator with multimovers under PWM (Pulse Width Modulation) feedback control employing the 3-D finite element method (FEM). The effectiveness of this method is shown by the comparison with the experimental results. Furthermore, the effect of a link-spring on each mover motion is(More)
Percutaneous catheter drainage (PCD) has been considered a standard method of relieving acute cardiac tamponade. Although conventional subxiphoid pericardiotomy is useful even for clotted hemopericardium, it has been believed to be unsuitable for emergency treatment because it is a time-consuming procedure. We report our modified pericardiotomy technique(More)
This paper proposes a novel magnetic structure of a linear oscillating actuator (LOA). The higher efficient magnetic structure is necessary for reduction in size and weight of an LOA. In a conventional optimization method using a genetic algorithm, it depends on an initial shape hard, and it is difficult to get a novel magnetic structure. In this paper, the(More)
This paper proposes an asymmetric acceleration drive method for linear oscillatory actuators under open-loop control. The effectiveness of this method is confirmed through the comparison of the 3-D FEM analysis results with the measurements of a prototype. Streszczenie. W artykule przedstawiono asymetryczne urządzenie oscylacyjne dla liniowych aktuatorów ze(More)
A 33-year-old man with hepatic bleeding was transferred to our hospital. Conventional plain and enhanced spiral computed tomography (CT) with a Siemens Somatom Plus-S scanner (Siemens AG, Erlangen, Germany) revealed a large hepatic hematoma and active extrahepatic bleeding. A unified spiral CT and angiography system (IVR-CT/Angio system; Toshiba Medical(More)
This paper proposes a feedback control method for a Linear Resonant Actuator (LRA), in which an external load estimated from two signals of the back-EMF is used as the target voltage in PID control. From the estimated load, it becomes possible to obtain an arbitrary amplitude of the mover. The effectiveness of this method was verified through FEM analysis(More)
The purpose of the present study was to evaluate the usefulness of a new gray-scale test pattern (NGTP) that was developed to easily adjust the gradients of thoracic CT imaging and enable visual consistency. The Society of Motion Picture and Television Engineers (SMPTE) pattern and the NGTP were used for comparison. The luminance character of two test(More)
In this paper, we propose a novel linear resonant actuator (LRA) with a 3-D structural magnetic circuit to improve its thrust characteristics . The effectiveness of the proposed actuator is verified through finite element method (FEM) analysis in which the magnetic field equation is coupled with the electric circuit equation, control method, and motion(More)