Research on a tri-axial force sensor based on MEMS technology for micromanipulation

A novel tri-axial force sensor used in micromanipulation is presented, which is based on piezoresistive detection and fabricated on a single-crystalline-silicon using MEMS technology. After modeling the sensor, finite element method (FEM) is used to analyze the deformation of cross-structure elastic cantilever. Then the calibration method for the tri-axial sensor is proposed, which is based on the technology of microscopic vision and the principle of cantilever bending deflection; and the signal processing circuit for the sensor output is presented. Experiment verifies that the sensor has the advantages such as: high intrinsic decoupling capability for strain gauge signals, high resolutions in all three axes, good linearity and repeatability and simple calibration. The sensor has the maximum measurement range of up to 10 mN with resolution of 2.4 μN in X-axis and Y-axis, and resolution of 4.2 μN in Z-axis.