Deformation Prediction Of Glass Substrate Based On Film Pressure Feedback

In recent years,with the development of large and thin glass substrates in the liquid crystal panels,in order to prevent the surface scraping,electrostatic pollution,and stress concentration in the transport process,the local porous floating transport has become a non-contact transport mode.In addition,the quality of TFT array will be detected by high-speed CCD camera on the production line,while the glass substrate is deformed due to the influence of the gas film pressure in the air floating transport system.The focal length of the CCD camera is limited,therefore the CCD camera will not be detected when the substrate has a large bending deformation or blurred condition,so glass substrate needs to be clear about its deformation in air floating transportation system.The deformation of the glass substrate can be detected by a laser displacement sensor,however,a large range of laser displacement sensors will make the production cost greatly improved and the detection efficiency is not high enough to achieve real-time detection requirements.Although the deformation of the glass substrate can be solved by the finite element analysis of the fluid solid coupling method,the application of the finite element solution software has a higher requirement on the computer configuration,the calculation time is longer and the efficiency is low.This method is used to provide evidence for the simulation results of the model.Therefore,it is necessary to propose an indirect way to detect deformation,so as to reduce production cost and improve production efficiency.In this paper,a kind of local porous floating transport platform is constructed,and based on this platform,a deformation prediction method based on the measured value fusion algorithm is introduced,which is to calculate the deformation of glass substrate by the pressure value measured by the test.The main contents of this research are as follows:1.The construction of partial porous air floatation transport platform and its working principle are introduced.According to the Darcy-Forchheimer law,the flow characteristics of the porous material are described and the mathematical model of the gas film pressure is established according to the flow characteristics.The results of the model solution and the CFD solution of the finite element analysis software are compared and analyzed to verify the correctness of the theoretical model.Finally,the influence of various elements in the guide rail on the gas film pressure is analyzed by Fluent simulation,and the rationality of the air floating guide is verified.2.The test scheme and test method of porous flow characteristics,gas film pressure distribution and bearing capacity are established.The experimental results are compared with the theoretical results of the model to further verify the accuracy of the theoretical model and the feasibility in practical application,which lays a foundation for the study of the deformation of the glass substrate in the air floating transport system.3.The finite element analysis software is used to solve the deformation of glass substrate in the air floating transport system.In order to verify the rationality of the solution,the glass substrate deformation measurement device of the air floating transportation system is set up.The results are compared and analyzed,and the change law of the deformation curve is analyzed,which provides the basis for the next chapter to study the deformation prediction method.4.The deformation prediction method based on the measured value fusion algorithm is proposed.The deformation of the glass substrate is calculated by the measured pressure data point.The deformation results are compared and analyzed with a single pressure point and multiple pressure points,and the deformation testing platform is built to verify the calculation results.