Development of Nano-Probe System for Nano-CMM (Coordinate Measuring Machinewith Nanometer Resolution)
Kiyoshi Takamasu, Professor, Department of Precision Engineering, The University of TokyoRyoshu Furutani, Professor, Department of Precision Engineering, Tokyo Denki University
1. Introduction

3. Conclusion

When developing micromachines and small optical elements, it isnecessary to perform traceable 3D measurements of the micromachine andits parts or the optical element in nanometer resolution. While practicaltechnologies for traceable measurements of surface shapes on a nanometerscale have been made achieved with scanning tunneling microscopes andatomic force microscopes, a measuring machine for measuring threedimensional sizes and positions has yet to be adequately developed. Thus,
it is necessary to develop a 3D measuring machine with nanometer
resolution, that is, a nanometer coordinate measuring machine (nanoCMM). The probe system in this nano-CMM has been deemed the mostdifficult to develop. In this study, a nano-probe system was developed by
combining mechanical contact with optical sensing of that contact.

As described above, we developed a nano-CMM and a nano-probe as
basic tools for developing future micromachines. However, there are many
issues that remain unresolved before these devices can be actually used,such as establishing a method for calibrating the measuring machine,
improving reliablity of measurements, and evaluating the device's aging.
Laser diodeQuadrant
photodiodeFig. 1 Basicprinciples of
the nanoprobe
system

2. Development of the Nano-Probe System
As shown in Fig. 1, the nano-probe system has a mechanicallysupported stylus ball that contacts the object to be measured and employs
an optical system for directly sensing displacement of the ball. With thismethod, it is possible to construct a 2D or 3D sensing system with stable
nanometer resolution for measuring objects having various surface aspects.
Fig. 2 shows the construction of the nano-probe system and its prototype.
A small ball having a diameter of 0.5 mm or less contacts the object, while
an optical sensor comprising a laser and a quadrant photodiode detects themovement of the ball during contact. The overall size of the apparatus isapproximately 100 x 30 x 30 mm, enabling the apparatus to be mounted in
the Nano-CMM. The resolution of the prototype nano-probe system wasevaluated and determined to be capable of achieving 10 nm or lessresolution. Further, when performing 2D measurements, crosstalk and thelike occurred between the X and Y axes. However, having achieved aresolution of about 10 nm, the probe system can be applied for the NanoCMM.

Object tobe measured

Stylus ball

150mmFig. 2 Construction of a nano-probe and its prototype

Micro Hand System Capable of 3-D Tracking
Tatsuo Arai, Professor, Department of Systems Innovation, Graduate School of Engineering Science, Osaka University
Tamio Tanikawa, Senior Researcher, Division of Intelligent Systems, Advanced National Institute of Science and Technology
In the future, we will apply these achievements in automanipulations
targeting such moving micro-objects as active cells.

1. Introduction
We have been developing an automated micromanipulation system forhandling and machining micro-objects under a microscope. In order toperform such auto-micromanipulations, we have developed a system for
automatically focusing the target object, a system for recognizing the object
in the focal plane and detecting its position, and a micro hand system that
integrates these two systems in order to control a two-fingered micro handto pick up objects while automatically tracking the movement of the object.

Y [ 애m ]252015102. Auto-focusing system

50

A characteristic quantity for determining the vertical relationshipbetween the object and the focal plane of an optical microscope is foundbased on RB data of an image around the object near the focal plane.
Accordingly, we developed a system for automatically tracking the focal
point of the microscope on the micro-object by deriving an algorithm forfocusing the object based on this condition. We configured a system thatapplies the same principle of controlling the micro hand in the direction ofheight for tracking the fingertips of the hand at the focal plane. We
achieved a tracking speed of 0.1 Hz (12 µm p-p).

-15-10-55101520-1025
X [ 애m ]reference position
actual position

Fig. 1 Overview of thesystem

3. Auto-handling a moving micro-object with themicro handUsing template matching, the positions of the fingers and the object in
the focal plane are automatically detected. Sufficient tracking accuracy formoving objects in the focal plane was achieved using a 60 x 60 pixel
template. We achieved auto-calibration required for accurately positioning
the micro hand by combining the auto-focusing with position detection in
the focal plane. Fig. 2 shows the absolute positioning accuracy achieved
through the calibration, which ensured within about 2 µm.
By integrating the above functions, objects could be picked up
automatically with the micro hand. Fig. 3 shows the micro hand performinga high-speed process to automatically pick up a glass particle 5 µm in
diameter.

Fig. 2 Positioning
accuracy withcalibration

Fig. 3 Automated object handling3