Micro ultrasonic motor for miniature robot arm

The purpose of this study is development of micro ultrasonic motor for miniature robot arm. It will be assembled to a miniature robot applied to a mesh robot to represent the shape and stiffness of the surface of objects. In the first stage, the authors have developed a micro motor by ultrasonic technology. It has two components: a stator (a cube of 3 mm size) and a rotor (diameter of 1 mm). The authors have designed a new stator and a rotor to increase output torque. The first trial motor shows successfully the potential of the final goal of 5 μNm and 3 rpm with a reduction gear system

Development of active stent moving by ultrasonic vibration

An active stent driving in a blood vessel has been developed by this study. A general stent is inserted in the stenosis part of a blood vessel and is the medical device used for expansion of a blood vessel. However, there is a problem of restenosis that a plaque accumulates around the stent. So, the active stent is used for removal of the plaque. The purpose of this study is drive of the active stent. And a design and a resonance experiment of the active stent were carried out. The active stent consists of two cylindrical receivers and one coil shaped stator. A drive source of the active stent is vibration of the stator. When the ultrasonic is irradiated to the receiver, vibration of the stator occurs. First, the receiver which resonates was designed by numerical analysis. The receivers different in the size based on the analysis result were made. And the size which resonates certainly by the resonance experiment was specified. Next, the active stent was designed. The active stents were made and the size which resonates by the resonance experiment was specified

Micro spherical ultrasonic motor using single spiral wire stators

The authors have developed Multi degree-of-freedom micro spherical ultrasonic motor using multiple spiral wire stators in previous research. In this research, the authors have developed the new spherical ultrasonic motor using single spiral wire stators. At the beginning, single spiral type wire stator was made. Next, rotational direction was controlled by duty ratio of traveling wave and standing wave. Then the drive properties of rotational speed and starting torque were clarified in this research. In the future, fixing method of wire stators without damping the vibration is needed to be planed. These results contribute to development of blood vessel endoscope which can move camera in any direction

Evaluation of spherical ultrasonic motor for space in high temperature condition

Development of spherical ultrasonic motor (SUSM) for space is an aim of this investigation. SUSM is a motor of multi-DOF. It's necessary to clear the various conditions to use a motor at space. In this paper, to confirm the durability to the radiant heat from the sun, drive experiments of SUSM was conducted in high temperature condition. As a result, our SUSM maintained the drive performance in high temperature condition. Materials of piezoelectric elements and of adhesives used in SUSM for space were important elements to maintain its drive performance in space. Selection results of the piezoelectric element and the adhesive were also reported in detail

Multi degree-of-freedom micro spherical ultrasonic motor using wire stators

The authors have been developing a micro spherical ultrasonic motor for a blood vessel endoscope to observe a blood vessel and make a diagnosis. It has two degree of freedom in one joint. The endoscope with the motor enables a doctor to control a camera angle to the affected area on the wall of the blood vessel. Comparing to the conventional endoscopes operated by wire-drive with an optical fiber and wide-angle lens, it has the advantages of rotating the camera with a right angle to the wall and obtain a precise image. In this research, we have developed the prototype motor and showed the characteristics of it

Dispersion cancellation in high resolution two-photon interference

The dispersion cancellation observed in Hong-Ou-Mandel (HOM) interference between frequency-entangled photon pairs has been the basis of quantum optical coherence tomography and quantum clock synchronization. Here we explore the effect of phase dispersion on ultranarrow HOM dips. We show that the higher-order dispersion, the line width of the pump laser, and the spectral shape of the parametric fluorescence have a strong effect on the dispersion cancellation in the high-resolution regime with several experimental verifications. Perfect dispersion cancellation with a linewidth of 3\mu m is also demonstrated through 25 mm of water.Comment: 6 pages, 6 figure

Position error estimation of the underwater coordinate measurement machine using artificial neural network

Position error of the underwater coordinate measurement machine (UWCMM) is estimated using an artificial neural network (ANN). The UWCMM has a multi joint serial link and the position of an underwater robot attached to the tip is obtained from kinematics of the link. However, the inaccuracy of the kinematics model creates a position error. In order to improve measurement accuracy, an ANN model which estimate position error of the kinematics of the UWCMM using joint angles data is constructed. The ANN model was trained by 462 data and verified by 42 data. The error estimation result of the trained ANN reduces maximally 66.5 % of the average of the position error of the verification data

Finite element analysis of spherical ultrasonic motor using wire stator with support structure on waveguide

The authors are developing multi degree of freedom micro spherical ultrasonic motor using wire stator for vascular endoscope. Spherical ultrasonic motor with 20 times model is used to confirm the driving characteristics as experimental equipment. Wire stator is designed by assuming the introduction to a vascular endoscope and transient response analysis is performed by the finite element method compared with 20 times model. In this study, the authors improve new support structure on waveguide and investigate new influence of the attenuation of the traveling wave transmitted on the wire stator by analyzing and changing the condition of the model. In the future, the authors will measure the amplitude of the wire stator by experiment and verify the accuracy of the simulation

Mechanism evaluation of agricultural power assist suit under development

A Power Assist Suit (PAS) for agricultural work was developed in this study. The objective is to reduce the strain involved in agricultural labor by mounting motor- and spring-assisted mechanisms on the PAS. However, such mounting might affect the operation of the PAS. Hence, an evaluation method that uses the degree of freedom (DOF) of the joint motions defined on the basis of the operable range of motion of the human body with the limbs in basic positions is proposed as an indicator of the ease of mobility. The articular structure of the PAS for agricultural work was evaluated using this method, and the feasibility of the labor-assist mechanisms was examined by analyzing the motions. The mechanisms reduced the labor involved in fruit tree pruning, which requires lesser joint motions

Evaluation of spherical ultrasonic motor for space in high temperature condition

Development of spherical ultrasonic motor (SUSM) for space is an aim of this investigation. SUSM is a motor of multi-DOF. It's necessary to clear the various conditions to use a motor at space. In this paper, to confirm the durability to the radiant heat from the sun, drive experiments of SUSM was conducted in high temperature condition. As a result, our SUSM maintained the drive performance in high temperature condition. Materials of piezoelectric elements and of adhesives used in SUSM for space were important elements to maintain its drive performance in space. Selection results of the piezoelectric element and the adhesive were also reported in detail