Research On Abnormal Vibration Sensor Of Vehicle Chassis Based On PVDF

In recent decades,computer technology,electronic information technology and sensor technology have made tremendous progress.With the improvement of living standards,automobiles have entered the homes of ordinary people,and automotive sensor detection technology has been paid attention to and developed.It is widely used in automotive design,automotive safety detection,dynamic analysis,automotive installation and many other fields.Vibration information detection of automobile chassis can analyze the movement information of automobile chassis and even the whole vehicle,which is of great significance to the safety detection of automobile.In this paper,a testing and analysis system based on PVDF piezoelectric film for abnormal vibration of automobile chassis is designed.Firstly,the research significance and trend of abnormal vibration of automobile chassis are expounded,the causes of abnormal vibration of automobile chassis are analyzed,and the necessity of chassis detection is expounded.Then the sensor is summarized,and the piezoelectric sensor and its application in vibration measurement are introduced.The commonly used piezoelectric materials are classified,and the properties and advantages of PVDF piezoelectric films are briefly described.On the basis of this,the present situation and application of PVDF piezoelectric films are studied.Then,through the deduction of the cantilever beam structure,the PVDF piezoelectric sensor is proved theoretically that it can be used to measure the vibration physical quantity of the beam.Based on the huge difference of the response of the cantilever beam to the vibration sources in different directions,combined with the vibration analysis of automobile,the structure model of the sensor is put forward,three transducer structures of the movable cantilever beam are designed,and the material selection is given according to the structure model.Using finite element simulation software to simulate and analyze the cantilever beam,the generated voltage of the cantilever beam under external load can be obtained.The influence of the parameters of the cantilever beam on the output voltage,such as the length and width of the cantilever beam,the thickness of the metal substrate and the thickness of piezoelectric film,and the selection of different substrate materials,is studied.Then through modal analysis,it is concluded that the natural frequency of cantilever beam decreases with the increase of length and width.Therefore,the natural frequency of the cantilever beam can be adjusted by changing its length and width to meet the needs of sensors in different frequency ranges.Finally,the hardware and software parts of the sensor are designed to complete the functions of sensor information processing and display.Finally,the prototype is tested experimentally,and an experimental platform is built to study the output characteristics of the prototype at different frequencies.The results show that the sensor can distinguish different vibration sources.By analyzing the voltage,the abnormal vibration parts can be analyzed.