Using a simple rapid heating process, Pb(Zr(0.52)Ti(0.48))O(3) (PZT) thick films prepared by hydrothermal method were separated from a Ti substrate. Scanning electron microscopy (SEM) revealed that the self-separated films were crack-free. After solution infiltration and high temperature annealing, the PZT thick films were shown to possess good electric properties. At 1 kHz, the dielectric constant and the loss were 593 and 0.05, respectively. The remnant polarization was 30.0 muCcm(2) at room temperature. A high frequency single element ultrasound transducer fabricated with these films showed a bandwidth at -6 dB of 73% at a center frequency of 67 MHz.

This paper describes a support system for ultrasound (US) probe scanning by a robotic probe holding system to support manual handling of an US probe. The system, consisting of an US probe manipulator with parallel link mechanism and a 6-axis force sensor, is able to hold and manipulate an US probe according to force applied to the probe by a technician. To enable the smooth coordinated control, compliance control is used. Moreover, we have proposed velocitydepended viscosity depending on the velocity of the robot. In this study, the appropriate viscosity corresponding to operational velocity was measured experimentally and the feasibility of the coordinated motion control was validated. The results of the viscosity measurement showed a clear inverse correlation between the viscosity and the operational velocity. In the coordinated motion control evaluation, the relation between the applied force and the robot velocity in the viscosity of high, low, and dynamic velocity-depended coefficient was measured. The result showed the dynamic velocity-depended viscosity provides well-coordinated motion in any operational velocities. The results demonstrated the system has a great potential for support of US diagnosis as an auxiliary medical robot.

This paper provides a robotic ultrasound transducer positioning system for minimally invasive ultrasonic therapy by manipulating microbubbles in blood vessel, aiming at effective high-intensity focused ultrasound (HIFU) and acoustic drug/gene delivery. To realize such a technique in vivo, accurate and dynamic positioning of an ultrasound transducer is required. For this purpose, we have recently developed a robotic system with a parallel link structure. The novel system consists of the newly developed robot with an ultrasound transducer, an optical tracking device, and an ultrasound imaging device. As an interface for robot control, we have also developed a planning software to plan target position and direction on an echogram. The optical tracking device is used to integrate the robot and the echogram coordinates. To validate the system feasibility, this study evaluated the system performance by conducting experiments of microbubble manipulation in an artificial blood vessel.

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