Research On Tangential Force Amplification And Position Direction Detection Mechanism Based On Piezoelectric Principle

With the progress of modern science and technology,especially for the rapid development of robotics,tactile sensor is one of the key technologies to ensure its accurate and efficient work.Although tactile sensors are mature in detecting normal force and have achieved remarkable results,in order to make robots work like human beings,it is necessary to make them have the ability to detect tangential force information.Therefore,based on the study of tangential force tactile sensors,this paper designs two structures for detecting tangential force: tangential force signal amplification structure and tangential force position and direction detection structure.This paper mainly studies and verifies the mechanism of the two structures.Firstly,the research status of tactile sensors at home and abroad is analyzed,the principles and applications of various sensors are studied,and the challenges and development trends of tactile sensors are analyzed.Then,two kinds of tangential force tactile sensing detection structures designed in this paper are introduced,and two kinds of structural design principles and related manufacturing processes are introduced respectively.Finally,the piezoelectric sensing principle used in this paper is introduced,and the performance of the PVDF piezoelectric film and the equivalent circuit of the PVDF piezoelectric film used in this paper are analyzed in detail.After analyzing the structural design principle,this paper first simulates and experiments the tangential force amplification structure.The internal stress and strain distribution of PVDF film in interlocking wave structure,square wave structure and trapezoidal structure are analyzed,and the effects of different structures,sizes and Young's modulus on the tangential force amplification effect are analyzed.Then,the experimental verification of the three interlocking models is carried out.The results verify the amplification effect of the interlocking structure on the tangential force signal.This paper also experiments on the size factor,structural factors and Young's modulus factors that affect the amplification effect.In this paper,the planar array structure is simulated and analyzed experimentally.Firstly,the polarization distribution of PVDF films at different positions in planar arrays with 2 and3 cross-sections is analyzed,and the function of planar arrays is explained theoretically.Then,the experimental verification of planar arrays is carried out.The results verify the detection function of planar arrays for the position and direction of tangential forces.Finally,this paper combines the amplification structure with the planar array structure for experiments.The experimental results verify that the two structures can work together to achieve both the amplification of the tangential force signal and the position and direction of the tangential force.