Jiamin Liu

A MEMS vibration sensor based on Mach Zehnder interferometers

Two micro-optomechanical accelerometers based on Multi-Mode Interference (MMI) couplers were designed and evaluated in this study. The optical components were optimized with the Parameter Scan Method. According to the photoelastic effect, the change in refractive index of a waveguide made of crystal materials is related to the mechanical strains in the waveguide. In this study, such change was calculated using the mechanical strains obtained from the Finite Element Analysis (FEA) results. Beam Propagation Method (BPM) was used to study the relationship between the input acceleration and the output optical power and thus the performance of the proposed accelerometers. The results show the two designs are suitable for different acceleration ranges.

Measuring three-axis force with four-part tactile sensing techniques

In order to measure three-axis force, two four-part tactile sensing systems based on piezoelectricity and optics were designed and fabricated. The feasibility and reliability of the two systems were evaluated both numerically and experimentally. A general formula between the applied three-axis force and the four-part tactile sensing signals was developed. It is expected that this formula should benefit the design and fabrication of new tactile sensing systems.

Significance evaluation of geometric features in classification of chinese facial images

In this paper, multivariable linear regression analysis was employed to obtain the relationship among facial geometric features, and a discriminant function was used to evaluate the significance of different features. Finally, classification rates were compared with different combinations of geometric features. The results showed that the geometric feature with more significance probably improved the classification performance in the cases studied.