Force measurement of the micro objects is very important for micromanipulation. For high accuracy, stiffness of the finger tip can be reduced for force measurement. It is not suitable for manipulation. So we consider to evaluate the stress on the micro structure to measure the force. Force measurement based on stress information has advantages when the structure is miniaturized. This can be shown by the scaling analysis. Hence, we propose a new force measurement and micromanipulation method using the laser Raman spectrophotometer (LRS). We design a micro gripper that employs the proposing force measurement method. We show experimental results of force measurement with the analytical evaluation to explain the effectiveness of the proposed system.

Micro manipulation is required for assembling and maintenance of micro machines and their parts. As the handling objects are miniaturized, attractive forces such van der Waals force, surface tension force and electrostatic force between micro objects and gripper surface become dominant in the air, and they work as adhesive forces. We cannot neglect such adhesive forces in micro manipulation. Considering the physical phenomena in the micro world, we propose reduction methods of adhesive forces. Surface roughness of the endeffector surface is effective to reduce the van der Waals force. We propose to make micro pyramids on the end-effector surface by micromachining techniques. We designed and made a prototype of the micro gripper with a micro end-effector whose gripping surface is covered with micro pyramids. Experimental results show effectiveness of micro pyramids for reduction of the adhesive force. We also made a semiconductor strain gauge at the end of the micro end-effector surface for force measurement. Both micro pyramids and the integrated piezoresistive force sensor are fabricated on the micro end-effector by the micromachining techniques. Performance of this force sensor is shown.

Micro manipulation is required for assembling and maintenance works of micro machines and their parts. This paper proposes a handling strategy for micro objects based on micro physics. Attractive forces are modeled and their reduction methods are presented. The authors show experimental results of reducing these forces. Based on the proposed reduction methods, the authors present a new micro manipulation strategy. Grasping of the micro object or press motion is required in some situations, and force information becomes important. The authors propose to use a laser Raman spectrophotometer with single crystal silicon and a strain gauge for the measurement and calibration of the force applied to the micro object. The experimental results of calibrating the force sensing system is presented.