Research On Piezoelectric Bionic Positioning Sensor Based On Scorpion Slit Sensor Adjusting Stress Field

With the development of science and technology,human-computer interaction,the Internet of Things and the metaverse are gradually being realised.Human-computer interaction and the interconnection of everything in virtual or real space by means of voice recognition,touchscreens,virtual reality and avatars in accordance with human consciousness and commands are gradually becoming possible.Human-computer interaction,the Internet of Things and the metaverse cannot be realised without highperformance sensors that collect information from the external environment and the interior of physical devices.In order to improve the performance of sensors researchers have developed "bionic ideas" and looked to nature for inspiration,resulting in the development of a range of high-performance bionic sensors.These bionic sensors are capable of meeting most human-computer interaction needs,but high performance sensors for bionic positioning are yet to be developed.In this paper,a piezoelectric positioning sensor that mimics the stitch receptor of a scorpion is proposed to enrich this field.At present,the research on piezoelectric sensors is mainly focused on the applications of vibration,acceleration and pressure,and there is little research on the applications in localisation.In order to overcome the disadvantages of existing sensors in terms of low sensitivity,low resolution,poor reliability and large size and cost,a piezoelectric bionic positioning sensor based on the scorpion slit sensor to regulate the stress field is proposed.Firstly,the Heterometrus petersii scorpion was selected as the bionic prototype,and the size,shape and material characteristics of its seam receptors were analysed to provide a basis for the design of the positioning sensor.Secondly,in order to investigate the modulation of the stress field by the multiple slit structure of the scorpion’s slit receptors,the effect of a single slit structure on the surrounding stress field was investigated.This paper demonstrates the modulating effect of the slit structure on the stress field and illustrates the distribution of the stress field around the slit structure.The experimental results show that the single slit structure can increase the sensitivity of the sensitive element(PVDF(poly(vinylidene fluoride))arranged around it according to an optimised curve by a factor of at least 2.9.Thirdly,in order to investigate the modulation of the stress field by the multi-slit structure of the scorpion suture receptor,a three-dimensional model was built and simulated by applying loads around it.The simulation results show that the multi-slit structure of the scorpion slit receptor modulates the stress field on it,as the vibration signals transmitted in different directions excite different stress fields on the scorpion slit receptor.A positioning sensor was designed and manufactured to mimic this functional structure of the scorpion slit receptor.Finally,a signal processing model for the positioning sensor is developed,resulting in a three-dimensional array that maps to a single factor,the relative orientation of the vibration source and the positioning sensor.The sensor is able to accurately measure the relative direction θ of the vibration source and the positioning sensor with an average error of 4.44°.The position coordinates of the vibration source are obtained by a simple mathematical operation based on the distance between the centres of the two sensors when the two sensors work together,with an average value of(6.68 mm,21.65mm)for the position measurement error.The paper investigates the effect of the slit structure on the modulation of the stress field,which increases the sensitivity of the sensitive element and produces different stress fields under different directions of loading.This principle is used to create a scorpion-like seam sensor that uses a piezoelectric thin-film set to detect changes in the stress field of a rigid element under the action of an external vibration source to achieve the positioning function,which has the advantage of small size and high accuracy.The positioning sensor is used to communicate with a computer,and human-computer interaction is achieved by applying vibration within the sensor’s measurement range.The text is divided into six chapters.The first chapter is an introduction.Chapter2 is a study of the morphology and behaviour of the scorpion.Chapter 3 introduces the bionic mechanism of this paper,the theory underlying the research and the power generation principle of PVDF piezoelectric films.Chapter 4 explores the modulation of the stress field around it by a single seam.Chapter 5 presents the study of the role of composite seams on its surrounding stress field,the fabrication of a positioning sensor based on the principle of composite seam modulation of the stress field and the testing of the performance of the sensor for it.Chapter 6 presents the conclusions and outlook.