Ken-ichi Kudoh

Precise positioning mechanism utilizing rapid deformations of piezoelectric elements

A driving method suitable for a micro mechanism is introduced. It utilizes friction and inertial force caused by rapid deformations of piezoelectric elements. A one-dimensional linear positioner using this mechanism consists of one main object put on a guiding surface, a piezo, and a weight. The weight is connected to one end of the main object via the piezo. By controlling rapid extension or contraction of the piezo, it can make step-like movements of several nanometers up to ten micrometers bidirectionally against friction. By repeating this step movement, it can move for a long distance. Using this mechanism, two types of joints for micro robot arm are developed. One is a simple rotating joint with an arm of 5 cm, and the other is a three-degree-of-freedom (DOF) joint with an 8 cm arm. Minimum step movements of the two joints were smaller than 0.1 mu m and maximum velocities were larger than 2 mm/sec at the end of the arm. Combining two joints, a four-DOF micro robot arm was developed.<<ETX>>

Effect of the Grain Boundary of Ice Crystals in a Frozen Gelatin Solution on the Dielectric Properties at a Subzero Temperature

The effect of the grain boundary of ice crystals in a frozen gelatin solution on the dielectric properties was investigated by the combination of a dielectric spectrometer and image analysis. A micro-slicer image processing system (MSIPS) was applied to measure the grain boundary properties as the perimeter density and number density of ice crystals. The perimeter density and number density of the ice crystals increased with increasing freezing rate. The dielectric properties of the frozen gelatin solution at various freezing rates were measured in the frequency range of 100 Hz to 100 kHz at −40 °C. The relaxation time did not affect the grain boundary properties. The perimeter density and number density significantly affected dielectric parameter ε0−ε∞ and electrical conductivity σ0. These results indicate that the dielectric spectrometer could be used to estimate the grain boundary properties in a frozen gelatin solution.

Rotational position control of biological cell by electrostatic force

We developed a biological cell rotation system using electrostatic force, which is excellent for manipulating a minute object. This system is the important element of an automated nuclear transplantation system. This system could rotate a mouses oocyte three dimensionally. And, it was confirmed that the rotation by electrostatic force did not influence fertilization and development ability of the oocyte.

Direct Electrostatic Transportation of Frozen Droplets in Liquid Nitrogen for Single Cryopreserved Cell Processing

This paper reports on a droplet transportation technology in liquid nitrogen for cryopreserved biological cell processing. The technology can directly transport frozen droplets in liquid nitrogen by electrostatic force. Low-frequency voltage is utilized to realize synchronous transportation, and thus positioning control can be easily realized. Transportation characteristics were investigated using frozen droplets of 0.3 M mannitol solution, Fluorinert FC-77, and deionized water in liquid nitrogen. The detailed motion measurement using mannitol solution confirmed that a frozen droplet is positioned at a point where electrostatic field is strongest and that a droplet motion is synchronized with the movement of generated electrostatic field.

3D image of protein visualization in a whole rice grain using an automatic precision microtome system

The 3D image formation technique using confocal microscopy has allows visualization of the 3D chemical structure in small parts of the bio-body. However, the large-scale 3D structure such as the distribution of chemical components throughout the whole body has not been shown. To allow such large scale visualization of the 3D internal analysis technique for bio-body has been developed.

Development of an Internal Observation System for Biological Samples Using Manipulators

In this study we developed a new type of internal observation systems for biological samples. Manipulators which take a small sample of tissue at the surface of a sliced sample are attached to this system. This system consists of a slicing blade, automatic sample feeding mechanism, a bioptome which takes a small sample of tissue at the surface of a sliced sample, and a microscope for observation.

Development of an Internal Observation System for Biological Samples Using Image Scanner

We have developed a Micro-slicer image processing system for visualization of the internal structure of living organisms and food samples. However with the conventional system, it is necessary to calibrate the obtained 2-dimentional images. This is due to a lack of uniformity of luminance or color of images obtained from the sliced sample. The new type Micro-slicer is equipped with a direct translation blade and automatic sample feeding mechanism. A scanner is attached in the system for acquisition of images. By taking the advantages of our proposed system, we can avoid calibration process to the obtained 2-dimentional images.