Study On Electronic Skin Sensing Characteristics Based On Array PVDF Fiber

Industrial robots are an indispensable part of today’s manufacturing industry to become digital and intelligent.In recent years,due to the shortcomings of traditional industrial robots using pre-programmed work,and at the same time,the need for machine work in a specific complex environment has put forward higher requirements for robots,that is,robots should have the ability to interact with humans and computers.In the future,the trend of scientific and technological development must be that a new generation of robots and people in the same workplace,coordinated cooperation,free interaction.For a new generation of robots to be able to cooperate and interact with humans,it is essential to have the robot’s perception ability,that is,to have an electronic skin.Electronic skins are not only used in robots,but also in smart wearable devices,medical rehabilitation,and even the popular metaverse today.Therefore,an array-type electronic skin flexible tactile sensor is designed and prepared,and the specific research content is as follows:(1)According to the structure and tactile principle of human skin,by comparing various piezoelectric materials,the piezoelectric material polyvinylidene fluoride(PVDF)was finally selected to prepare electronic skin.Design special brushed fiber equipment,using metal molybdenum wire drawing to produce suitable PVDF piezoelectric fiber.The surface of the fiber is coated with conductive silver paste as an electrode,and the superconductive carbon black water solvent is injected inside as another electrode for polarization to obtain liquid core PVDF piezoelectric fiber.The liquid core PVDF piezoelectric fiber was embedded in the selfmade device in the form of an array,and encapsulated with human silicone rubber to prepare an array-type electronic skin.(2)Taking piezoelectric effect as the sensing principle of electronic skin,according to the first type of piezoelectric equation,the sensing mathematical theoretical model of PVDF piezoelectric fiber of liquid core with simple support beam structure was established,a twodimensional mobile experimental system platform was designed and built,and an electronic skin was prepared by using a single liquid core PVDF piezoelectric fiber for signal calibration experiment,and the results showed that the signal size of the electronic skin was the signal waveform amplitude,which verified the theoretical model.The exciter and thrust meter were used to carry out the sine wave and square wave excitation experiments of different frequencies and different amplitudes of the arrayed electronic skin,and the results showed that the frequency,amplitude and shape of the excitation waveform and the output signal waveform corresponding to the electronic skin were highly consistent,and the distance between the force point and the piezoelectric fiber was inversely proportional to its output signal.(3)The feasibility of electronic skin array is verified and the results show that the output signal of piezoelectric fibers at different positions is consistent,the response time of piezoelectric fibers at different distances is small,and the output signal decreases with the increase of distance.The covered impact test platform was built,and the thrust meter was used to impact each coordinate of the array electronic skin to different degrees,and the results showed that the force response of all coordinates of the array electronic skin was distinct,the force was proportional to the output signal,and the maximum range was ION.The signal samples were trained and learned by using the BP neural network algorithm and classification learning of the signal samples,and the training results showed that the correlation and learning degree of the signal samples were high.Based on machine learning,a GUI program dedicated to the electronic skin is produced,which can accurately display the magnitude and force point of the impact force of the electronic skin.Through theoretical analysis and sensing performance experiments,the results show that the array type electronic skin flexible tactile sensor designed and prepared in this paper has the characteristics of simple preparation process,low cost and accurate force capture,and is a flexible bionic electronic skin with excellent sensing performance.This electronic skin can be used in smart manufacturing,wearable devices,medical rehabilitation equipment,etc.