Research On Mass Detection And Fluid-Structure Interaction Vibration Characteristics Of Microcantilever Structure

In recent years,the microcantilever sensor has been widely used in the fields of biology,medicine and chemistry as a useful label-free mass detection tool.Conventionally,the mass is detected by inversely solving the dynamic model that correlates the adsorbed mass to the shifts in the resonant frequencies of the cantilever before and after the adsorption.However,the information of the particle’s position is required prior to the measurement.In fact,it is difficult to accurately measure the particle’s position in many cases,and in the process of the measurement,the deviation of position’s measurement will lead to the deviation of mass detection.In addition,many applications need sensors work in fluid environment,and the fluid damping can be obvious influence on the quality of the sensor precision.Therefore,it is of great importance to study the effects of fluid damping on the characteristics of microcantilever structure resonators.According to the above problems,the main research contents of this paper are as follows:(1)The double detection model of mass and position based on microcantilever was derived,and its accuracy was verified by finite element simulation.The influence of the position and mass of attached particles on its accuracy was also studied.(2)In practical application,the micro cantilever beam is fragile and difficult to encapsulate.The double detection model of the mass and position based on the cantilevered micro-plate was proposed depend on the double detection model of mass and position based on microcantilever,which was verified by finite element simulation.The influences of the aspect ratio of the cantilevered micro-plate,the mass and position of the attached particles on its accuracy were also studied.(3)In order to further study the influence of fluid damping on the performance of microcantilever mass sensor,the resonant frequency solving model of the cantilevered microplate in the non-viscous fluid was deduced,and the viscous and non-viscous finite element models were established to verify it.At the same time,the influence of the aspect ratio of the cantilevered micro-plate and the fluid viscosity on the fluid-structure coupling vibration characteristics of the cantilevered micro-plate was studied.(4)Finally,the resonant frequencies before and after the cantilevered micro-plate attached to the particles were measured,and the double detection model of mass and position based on the cantilevered micro-plate was verified.At the same time,the resonant frequency and quality factor of the cantilevered micro-plate in the air were measured,and the solution model and the finite element model of the resonant frequency of the cantilevered micro-plate were verified.