Stereovision-based control for automated MOEMS assembly

Microassembly represents a very promising solution to microproducts and complex Micro-Electro-Mechanical Systems (MEMS) fabrication. Since, in the case of teleoperated assembly, an operator is the main source of errors, there is a great interest in microassembly automation. Its main issue consists in precise estimation of object position. Previous studies demonstrate the possibility of application of modelbased visual tracking algorithms from ViSP (Visual Servoing Platform) library. However, the methods of macroassembly cannot be directly applied when working with microobjects. The characterization of single-view visual tracking notably revealed the complexity of depth estimation in microscale, which is due to small depth variation in the seen images compared with the distance from camera. So, an algorithm of Z coordinate reconstruction using a second camera was developed and analyzed for visual servoing task. It was then used to automate microassembly. Experiments demonstrate the possibility of complex microcomponent automatic microassembly with precision better than 10 micrometers.