Research On The Angular Acceleration Sensing Mechanism Of Mechanical Bionic Membrane Semicircular Canal System

The main function of the membrane semicircular canal in the human vestibular system is to perceive the angular acceleration of the head to maintain body balance,maintain clear vision and perceive spatial posture.Due to the complex and delicate structure of the membranous semicircular canal and its deep burial in the temporal bone,the biomechanical response of the membranous semicircular canal cannot be measured directly by existing techniques.Therefore,not only the lack of in-depth understanding of its working process and perception mechanism,but also affect the diagnosis and treatment of related vestibular diseases.In this paper,artificial materials are used to simulate the biological tissue in the membrane semicircular canal of human body,and a one-dimensional bionic membrane semicircular canal physical model is designed and prepared according to the proportion;Based on this physical model,a theoretical model of angular acceleration perception of membrane semicircular canal was established;The experimental system was set up to verify the theoretical model and study the sensory mechanism of membrane semicircular canal.The specific research contents are as follows:1)Modified medical simethicone was used to simulate the endolymph in the membrane semicircular canals of the human body.Experimental measurements show that the density of the bionic endolymphatic fluid is 1g/cm3,the viscosity is 7.65×10-4 Pa·s,and the viscosity temperature coefficient is 0.417,which is similar to the performance of human endolymphatic fluid.2)The Young’s Modulus of AB elastic film and PDMS elastic film were measured by TriboIndenter In-Situ Nanomechanical Test System;In addition,the Density,Poisson’s Ratio and Young’s Modulus of PVA/GEL hydrocoagulable film were measured by Sand Burying Method,Image Tracking and Micro-Stretching Composite Method.The test results show that the mass ratio of 6:1 PVA/GEL hydrocoagulant film prepared by "freezing method" is 1g/cm3,Poisson’s Ratio is 0.479,Young’s Modulus is 86.449 Pa,which is basically consistent with the performance of human cupula ampullaris,suitable for the preparation of bionic cupula ampullaris.3)The one-dimensionally enlarged shell of the biomimetic membrane semicircular canal was fabricated by 3D printing technology in a 1:4.5 ratio.One-dimensional biomimetic membrane semicircular canals were fabricated after installing bionic cupula ampullaris and encapsulating biomimetic endolymph.Based on Navier-Stokes Equations,the theoretical sensing model of membrane semicircular canal with volume displacement of cupula ampullaris is derived under constant angular acceleration,impulse angular acceleration and sinusoidal excitation in horizontal plane,considering the viscosity of lymphatic fluid and kinematic boundary constraints.On this basis,the relative displacement and time constant of the bionic cupula ampullaris of one-dimensional bionic membrane semicircular canal under excitation conditions were tested by setting up an experimental system.The experimental results show that the displacement of the biomimetic cupula ampullaris has a linear relationship with angular acceleration,and the cupula ampullaris displacement curve obtained verifies the accuracy of the theoretical model.4)The theoretical model of membrane semicircular canal perception in plumb plane was established on the basis of the theoretical model in horizontal plane considering the influence of gravity.The experimental system was set up to measure the relative displacement of the bionic cupula ampullaris in the one-dimensional bionic membrane semicircular canal under constant angular acceleration,impulse angular acceleration and sinusoidal excitation.The experimental results show that the deformation of the cupula ampullaris was inhibited by the gravity factor in the plumb plane,that is,the relative displacement of the cupula ampullaris decreases under the same conditions;At the same time,the results verify the accuracy of the theoretical model.Theoretical model and experimental results show that the bionic membrane semicircular canal designed and prepared in this topic has highly similar biomechanical properties to the human membrane semicircular canal,and can simulate the working process and perception principle of the human membrane semicircular canal.Theoretical model and experimental results show that the bionic membrane semicircular canal designed and prepared in this paper has highly similar biomechanical properties to the human membrane semicircular canal,and can simulate the working process and perception principle of the human membrane semicircular canal.The research method proposed in this paper is helpful to further study the working principle of the membrane semicircular canal of human body and promote the development of the diagnosis and treatment technology of vestibular diseases.