Design And Analysis Of Bionic Chewing Food Texture Analysis Model

At present,food texture evaluation methods mainly include sensory evaluation method and instrument measurement method.Sensory evaluation method is closest to human sensory reality,but it has certain subjectivity and limitations,so it is difficult to obtain unified and objective evaluation results for food texture.Instrument measurement method usually uses texture instrument to change different shapes of indenters to extrude food to obtain texture results,but the indenters extrusion process is far from human chewing movement,and can not accurately reproduce the temperature and humidity of the oral environment.Device for chewing food texture analysis is on the basis of real human oral system and structure,using reverse engineering technology,access to human oral real size,the 3 d modeling software in processes such as design,motion simulation machining for a device for chewing,supplemented by software control system,able to complete the texture of the evaluation of different foods.Therefore,in order to improve the accuracy of food texture evaluation,this paper uses reverse engineering technology,three-dimensional modeling technology,ADAMS kinematics analysis,ABAQUS motion simulation and other technologies to design a biomimetic chewable food texture analysis model that is close to the actual human oral cavity,and predicts the motion performance and stability of the model.The implementation of this paper provides theoretical reference and technical support for the research and development of the biomimetic texture analysis device for chewing food.The research contents are as follows:(1)To study the structure and function of the human oral cavity.Using reverse engineering technology and referring to human oral system and real oral size,threedimensional modeling software CATIA is used to model the texture analysis model of biomimetic chewing food,including biomimetic upper and lower jaw,biomimetic teeth,input shaft and other components.In this study,the connecting rod mechanism was used as the driving mechanism,the input shaft was connected to the connecting rod,and the connecting rod directly drove the mandible.The stretching spring was set at both ends of the mandible to simulate the masticatory muscle,and the jaw was driven to complete the occlusal movement together.Whether the DMU simulation analysis model is reasonable and there is interference.The results show that the biomimetic chewable food texture analysis model has no interference,and the driving mechanism is reasonable,which can restore the human chewing movement.(2)The texture analysis model of biomimetic chewing food was imported into the motion analysis software ADAMS 2017,and the kinematics simulation analysis of the driving mechanism,the whole model and the movement of the jaw were carried out respectively,and the stability and movement performance of the model were verified by comparing with the movement results of human oral cavity.The maximum opening of the jaw is 18.80°,and the maximum movement displacement is 18.08 mm within the range of the maximum opening of the human body.There is no interference,and the model has stability and good movement performance.(3)The biomimetic chewing food texture analysis model is imported into the finite element analysis software ABAQUS,the connecting rod,the input shaft and the mandible are respectively analyzed for the 8th order vibration mode,and the vibration state model diagram and natural frequency are extracted at the same time.The natural frequency of the input shaft increases with the order of the vibration mode,showing a slowly increasing trend.From the 1st to the 8th order,the frequency increases from 1.09 to 8.92Hz;the natural frequency of the connecting rod presents irregular changes.The maximum frequency is 7.04;the natural frequency of the whole machine model increases with the increase of the vibration mode order,ranging from 182.64 to 905.38 Hz;the above results show that the bionic chewing food texture analysis model is not easy to resonate when it moves,and it is stable.Select the full teeth in the bionic chewing food texture analysis model to simulate fruits and vegetables,grains,and other types of food.The Mises stress,maximum principal stress,and maximum shear stress of fruits,vegetables,cereals,and other types vary with the type The change showed a gradually decreasing trend,and the stress mainly occurred at the molars.The single-tooth molars are extracted for simulation,and the stress results show a similar trend to the full-tooth simulation.(4)In the TPA mode,the texture results of white radish,peanut and QQ candy were obtained by sensory evaluation method,and the correlation analysis was carried out with the movement simulation results of the texture analysis model of bionic chewing food.Then the correlation analysis was carried out between the sensory results and the texture analyzer results equipped with common indentation head and imitation tooth indentation head respectively.The maximum principal stress was significantly correlated with sensory hardness,brittleness,elasticity,cohesion and masticability(r=0.956,0.969,-0.921,-0.918,-0.986).The maximum principal stress of single tooth simulation was also significantly correlated with the sensory results(r=0.941,0.956,-0.901,-0.898,-0.977).The maximum principal stress of full-tooth and single-tooth simulation can effectively reflect the texture parameters of food,including hardness,brittleness,elasticity,cohesion and chewability,and full-tooth simulation is better than single-tooth simulation,that is,the biomimetic chewable food texture analysis model can effectively predict the texture of food.The evaluation results of the texture of the imitating head were significantly correlated with the sensory hardness,elasticity,cohesion and masticability(r=0.999,0.984,0.999,0.892),which were better than that of the ordinary indentors.The evaluation results of the texture of the imitating head were closer to the actual human sensory experience.