Towards fully-automated micrograsping for microassembly

Fully automated microassembly procedure has become an essential subject of interest among microsystem researchers due to the promising potential of the establishment of fully functional Micro Electro Mechanical System (MEMS) devices and significant cost reduction on large number of consumer based products once the system is realized. In the heart of microassembly, the development of high precision micrograsping technique for dexterous manipulation of minute parts becomes the key factor which determines the success of microassembly process. This paper presents the development of a microgripper for the purpose of manipulating micro sized objects in precision environment. The gripper is realized based on compliant mechanism concept that uses flexure hinge to replace the traditional rigid hinge due to its favorable advantages of eliminating the backlash and coulomb friction problems. Modeling of this gripper was performed utilizing a combination of Pseudo Rigid Body Model (PRBM) and Finite Element Analysis (FEA) which effectively accelerates the prototyping procedure. The gripper was cut out of aluminum plate using electro-discharge machining (EDM) technique and experimental studies were conducted to investigate the performance as well as for model verification. The result between experiment and computational analysis has shown high degree of agreement. High displacement amplification was successfully recorded and maximum stroke of 100 mum can be achieved.