Novel MEMS grippers capable of both grasping and active release of micro objects

Due to force scaling laws, adhesion forces at the micro scale make rapid, accurate release of micro objects a challenge in pick-place micromanipulation. This paper presents a new MEMS microgripper integrated with a plunging mechanism to impact the micro object for it to gain sufficient momentum to overcome adhesion forces. The performance was experimentally quantified through the manipulation of 7.5-10.9 mum borosilicate glass spheres in an ambient environment under an optical microscope. Experimental results demonstrate that the microgripper achieves a 100% successful release rate (based on 200 trials) and a release accuracy of 0.70plusmn0.46 mum. Experiments with conductive and nonconductive substrates also confirmed that the release process is not substrate dependent.