No abstract

This paper reports on a study of the scanning electron microscope (SEM) Moiré method. Tests were carried out by rotating the specimen grating slightly with respect to the electron scanning raster lines, to verify that the Moiré images captured were really due to the interference between specimen and reference gratings. The experimental results coincided well with the calculated theoretical values and with small measurement errors. Then, the shear strains experienced by the solder joints of a flip‐chip ball grid array specimen were investigated using the SEM Moiré method. The results were compared with those obtained using the optical Moiré method.

No abstract

Precision control is a very important aspect in many areas of engineering. In the field of biotechnology, there is an increasing need for high precision sensing, positioning and manipulation of cells and other biological entities. In the field of medicine, positional accuracy greater than what human hands are capable of achieving is required in some surgeries. The introduction of a highly precision manipulator will assist in biological research on micro-sized cells, helping to save time and manpower costs. The use of micro robots for handling dangerous or unknown biological cells or drugs avoids human contact and the risk of contaminations. Grasping and manipulating micro-objects is also required for a wide range of important applications such as the assembly of micro-components to obtain microsystems in electronics industry. The manipulation of objects of the size ranging between 1 mm and 1 µm would present a challenge to researchers. The possible applications are the handling of micro-parts of complex shapes in restricted environments with difficult access, in vacuum environments or cleanrooms, where adhesive or vacuum gripping is not suitable. Thus there is a demand for an inexpensive gripper with properties like loss-and backlash-free motion transmission, small size, special materials and integration of sensory properties. An effective mechanical micromanipulator should possess the ability to grasp steadily objects with different shape, high positioning accuracy and large number of degrees of freedom. The manipulators for biological applications should be able to work in liquid solution and sterile environment, accurately control grasping forces in order to ...

No abstract