A High Sensitive Mass Sensor for Robotic Applications

Abstract

In this study, a new design of cantilever is proposed in which the cantilever geometry is optimized for achieving high resonant frequency so that small mass changes can be measured accurately. Various sources of noise can be suppressed by making the resonant frequency of cantilever as large as possible. Rectangular, rectangular-stepped and triangular-stepped geometries of cantilevers are designed and analyzed by using commercial finite element analysis software ANSYS Multiphysics. The resonant frequency obtained from simulations is compared with theoretical formulae and coherency of the result is obtained in most of the cases. Properties of stainless steel material is used for all the cantilever geometries with mass density 7800 kg/m 3 , Elastic modulus 200 GPa and Poisson's ratio 0.30. Results show that triangular-stepped profile has higher resonant frequency than all the other geometries. Limited of detection using change in frequency with change in mass is analyzed to compare the sensitivity of rectangular and triangular-stepped geometries. Triangular-stepped geometry exhibits highest sensitivity as compared to other two designs.