Experimental validation of in-hand planar orientation and translation in microscale

Abstract

This paper presents the experimental validation of automatic dexterous in-hand manipulation of micro-objects. Currently, precise handling of micro-objects is still a challenge, especially when large rotations are required. Indeed, the current dexterity of microgrippers is still very low and only some small range rotations have been shown. Although the robotic hands in the macroscale have better capabilities, they are not able to manipulate micro-objects. The proposed approach extends the capabilities of dexterous macrohands to the microgrippers enabling dexterous micro-manipulation. Design rules of the micro-hand fingers and trajectories enabling micro-manipulation are proposed. The developed methods are validated by simulation and on an original experimental prototype having three fingers (7 $\upmu$m in diameter). Half turns of $220\,\upmu$m square objects demonstrate the relevance of the approach which opens the way to new advanced in-hand micro-manipulation and micro-assembly methods.