Research On Topography Curve Sensing Technology Based On PVDF

Polyvinylidene Fluoride(PVDF)is a piezoelectric smart material with bidirectional reversible energy conversion characteristics.PVDF film has excellent characteristics such as strong piezoelectric performance,high stability,low acoustic impedance,wide frequency response,light weight,flexibility and good processing performance.PVDF film has strong embedding property,and it has a wide range of applications in the field of intelligent structures.Based on the analysis of surface contact sensing technology and shape sensing research status,this topic analyzes the current research status of shape sensing technology at home and abroad,and summarizes the basic characteristics and application research of PVDF materials.Based on the constitutive equation of the PVDF thin film and the analysis of piezoelectric coupling and thermoelectric coupling mechanisms,the superiority of the PVDF thin film in dynamic contact applications is discussed.Combining with the COMSOL finite element analysis software(DEMO version),the PVDF piezoelectric The model was constructed,and the charge distribution law and the relationship between contact force and surface charge in PVDF films were analyzed.Based on this research,the principle of topography sensing based on PVDF piezoelectric thin film was further studied,and the function relationship between the surface charge amount and the geometric features of the topography was established,and a specific type point recursive algorithm was developed,using Ferguson The curve model reconstructs the topographic curve.The algorithm is verified against a certain curve,and the results show that it has a good reconstruction effect,which verifies the feasibility of the sensing algorithm.Research shows that there is a certain mathematical relationship between the curve reconstruction error and the number of sampling points.Aiming at the error of the type point,the law of error distribution is further studied,in order to further reduce the curve sensing error and lay a certain theoretical foundation for the accuracy of curve sensing.Based on the PVDF topography sensing method,a curve topography sensing experiment was carried out,and a linear array of PVDF thin films was arranged.The contact force information was collected based on Lab VIEW software and the curve reconstruction was performed using MATLAB.The sensing curve was different from the original curve.A certain degree of coincidence proves the feasibility of this method.The causes of curve sensing errors and topographic reconstruction errors are further analyzed,which provides a basis for further improving the accuracy of curve sensing.