Abstract: Advanced engineering ceramics are more and more widely employed in modern
industries because of their excellent mechanical properties such as high hardness, high compressive
strength, high chemical and abrasive resistance. This paper investigates the high speed wire
electrical discharge machining (HS-WEDM) of Si3N4-based ceramics by assisting electrode method.
The theory of assisting electrode method is introduced. The machining phenomena under different
electrical parameters were studied and the optimized machine pulse width was got. The material
removal mechanisms change with the increase in the power of single pulse.
Abstract: Optical communication is gaining popularity in telecommunications; most obviously
evident is the increase in demand for a large variety of fiber optic components. V-groove structure
quality is critical to the functionality of the fiber connector as it governs the position of the optic
fibers. The main parameters, which determine the V-groove quality, include core pitch, surface
roughness and the position of centerline. In this paper, a series of cutting conditions were applied to
investigate the effect of different machining parameters on the V-groove quality. In the experiment,
the V-groove structure is machined by a 40° single crystal diamond tool on aluminium alloy with
different cutting conditions. Based on the findings, the relationship between the cutting conditions on
the surface roughness was explored. The implications of these findings on the improvement of the
surface finish of V-groove profile are discussed.
Abstract: Molecular techniques are transforming our understanding of cellular function and disease.
However, accurate molecular analysis methods will be limited if the input DNA, RNA, or protein is
not derived from pure population of cells or is contaminated by the wrong cells. A novel Ultrasonic
Vibration Microdissection (UVM) method was proposed to procure pure population of targeted cells
from tissue sections for subsequent analysis. The principle of the Ultrasonic Vibration Cutting is
analyzed, and a novel microknife is designed. A multilayer piezoelectric actuator is used to actuate a
sharp needle vibrating with high frequency and low amplitude (Approx. 16–50 kHz, and 0-3μm) to
cut the tissue. Contrast experiment was done to test the feasibility of UVM method. Experimental
results show that the embedded tissue can be quickly and precisely cut with the ultrasonic vibration
Abstract: A new Micro-WEDM machine is developed in this paper. Therefore, experiment can be
done on this machine. Especially, the surface characteristics of work-pieces are analyzed in detail.
The Micro-WEDM can machine micro slot easily. In addition, all kinds of micro shaped holes, micro
gears, complex micro parts and dies are machined to check its processability. A micro gear can be
easily fabricated by micro-forming method with the micro gear dies fabricated by micro-WEDM, and
get well performance, which indicates that micro parts machined by Micro-WEDM meet the
requirements of micro instrument and device.
Abstract: A new method for on-line fabrication of micro tool-electrodes is presented in this paper.
The method is base on the machining mechanism of electrochemical micromachining. By exchanging
the polarities of the tool-electrodes and workpiece repeatedly, micro tool-electrode appropriate for
electrochemical micromachining can be obtained through mutual machining. Because the processes
are carried out on-line, the position error and clamp error caused by twice-clamp of tool-electrodes
can be avoided, and the machining precision can be improved greatly. This method will be very
important to electrochemical generating micromachining. Experiments are carried out, and a
tool-electrode with the pinpoint of 20μm can be machined stably.
Abstract: Based on extensive study on literatures of control of parallel manipulators and serial
manipulators, control strategies such as computed torque control, PD+ control, PD with feedforward
compensation, nonlinear adaptive control are classified into two categories: model-based control and
performance-based control. Besides, as advanced control strategies, robust control and
passivity-based control for the parallel manipulators are also introduced. Comparative study in view
of computation burden and tracking performance are performed. It turned out that the physical
structure properties of parallel manipulators’ dynamics are similar with that of serial ones, and this
constitutes a common foundation for the two kinds of manipulators to develop together that control
design of parallel manipulators can start with ever established control methods of serial manipulators.
Abstract: A workpiece with a large surface area is likely to be uneven due to form error and waviness.
These geometric disturbances can cause inaccurate micro shapes to be formed when micro features
are micro-grooved into the surface and cause the resulting workpiece to fail to function as desired.
Thus, the real-time monitoring and compensation is required to guarantee the form accuracy of micro
features while machining the workpiece with a large surface area. In this study, a method is suggested
for real-time measurement and compensation of geometric errors for the micro grooving of a large
flat surface using a laser displacement sensor placed ahead of the cutting tool. Experimental results
show that the compensated surface profiles fit the measured ones within an allowable tolerance even
at cutting speeds as high as 200 mm/s.
Abstract: The procedure of structural design on miniaturized machine tool (mMT) is proposed and
structural optimization by applying robustness evaluation method is presented in this paper. The
design procedure of a kind of mMT which is a 3-axis miniaturized milling machine tool (mMMT) is
discussed and three different structures of mMMT are proposed based on previous design procedure.
The most suitable structure is selected using robustness evaluation method, which is Taguchi method,
due to volumetric error function. The design parameters of selected structure are optimized.
Abstract: This research work aims to explore the feasibility of applying electrochemical machining
(ECM) to micromachining. An experimental setup for micro-ECM has been developed. Lower
machining voltage, lower concentration of passivity electrolyte, high-frequency short-pulse power
supply and micro tool electrode rotating at high speed have been synthetically adopted to localize the
dissolution area in micro-ECM, so the machining gap can be kept at about 10 μm and the better
resolution of machined shape is achieved. A micro-hole with 45μm diameter is drilled on the stainless
steel foil with 100μm thickness. A new approach of fabricating microstructure by micro-ECM
milling with a simple micro electrode is proposed, and the micro beam with width of about 50μm
which has high precision is fabricated by micro-EC milling on the stainless steel foil (1Cr18Ni9Ti)
with 300μm thickness. A mathematics model has been established, which can be used to simulate the
process of shaping workpieces in the process of micro-ECM.
Abstract: A feeding table system is set up to meet the need for high motional precision and
super-slow speed in micro-electron discharge machining (micro-EDM). It is composed of a resonant
piezoelectric ceramics motor, a linear bearing and a linear encoder . It features high accuracy due to
the application of linear driving, closed-1oop feedback and elimination of abbe’s errors. The
characteristics of fine motion , slow speed and load capability are investigated. The results of the
experiments show that the stable fine motion of this system can be as little as 100 nanometer and its
speed can be as slow as 0.5 micron per second which is proper for feeding table of micro-EDM.