Design, fabrication and characterization of a flexible system based on thermal glue for in air and in SEM microassembly

This paper presents the design, fabrication and characterization of a device able to exchange the tip part (so-called the tools) of a two fingered microgripper. The principle of this tool changer is based on the use of a thermal glue whose state (liquid or solid) is changed by heating or cooling. Several kinds of pairs of tools have been designed. The suitable pair of tools can be chosen according to the size, shape and material of the object to manipulate. The tool changer enables one to perform a sequence of elementary micromanipulation tasks (i.e. an assembly sequence) by using only one gripper mounted on only one manipulator. The tool changer has been automated and successfully tested in air and in the vacuum chamber of a Scanning Electron Microscope (SEM). It brings flexibility to the micromanipulation cell and contributes to reduce the costs, the used space and experimentations time for micromanipulations in the SEM. The assembly of a ball bearing (the balls are 200 mu m in diameter) has been successfully tested using the microgripper equipped with the tool changer in a SEM. This tool changer has been designed for a microgripper but can be easily adapted to lots of other kinds of systems.