Shinnosuke Hirata

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Ultrasonic distance measurement using the pulse-echo method is based on the determination of the time of flight of ultrasonic waves. The pulse-compression technique, in which the cross-correlation function of a detected ultrasonic wave and a transmitted ultrasonic wave is obtained, is the conventional method used for improving the resolution of distance(More)
Distance measurement using an ultrasonic wave is suitable for environment recognition in autonomous mobile robots. Ultrasonic distance measurement with the pulse-echo method is based on determining the time-of-flight (TOF) of the reflected echoes. The pulse-echo method with pulse compression, the cross-correlation method, can improve the distance resolution(More)
The development of the instrumented indentation testing robot for bio materials with micro surface hardness and stiffness test is described. This micro surface measurement system is composed of the piezo-driven micro-robot with the indenter that can move to the measurement area precisely step by step with 1 μm per step on a metal plate and camera(More)
This brief proposes a frequency synchronization method for a full-digital self-oscillating pulsewidth modulation (PWM) signal generator. The self-oscillating PWM signal generator (PSG) generates a variable switching frequency, which results in poor drive performance for a three-phase power inverter or converter. The proposed frequency synchronization method(More)
Real-time distance measurement of a moving object with high accuracy and high resolution using an ultrasonic wave is difficult due to the influence of the Doppler effect or the limit of the calculation cost of signal processing. An over-sampling signal processing method using a pair of LPM signals has been proposed for ultrasonic distance and velocity(More)
Chronic liver disease requires careful follow-up during long-term treatment, and development of a quantitative diagnosis method for liver fibrosis based on an ultrasonic imaging system is highly desired. Texture analysis using a co-occurrence matrix was applied to both clinical and simulated ultrasonic images of fibrotic livers. A sequence of matrices was(More)
High DOF manipulation method is required under microenvironment. In the typical method of micromanipulation by surface tension, however, tilting or rotating of a target is difficult. The multi-needle-type capillary is proposed for high DOF micromanipulation by surface tension. The multi-needle-type capillary is composed of thin needles which are(More)