Research On Contact/Contactless Measurement Technology Of Complex Surface

Complex curved ceramic structural parts have good electromagnetic wave penetration characteristic,aerodynamic characteristics and can withstand the harsh environment of the outside world,and are widely used in key parts such as aircraft nose cones.With the continuous development of technology,the performance requirements of ceramic structural parts are gradually improved.The high-precision machining of complex curved ceramic structural parts has become a bottleneck problem that needs to be broken,and measurement is the key to ensuring the quality of complex curved surfaces.In this paper,measurement strategy for coupling measurement with non-contact measurement is submitted.Because the contact measurement in the current complex curved ceramic structure is low in efficiency,the non-contact measurement is greatly affected by the measured surface characteristics,and the secondary loading error and measurement range are too small.Based on this measurement strategy and considering the actual measurement conditions,the design of the measurement prototype is completed.The prototype can be connected to different machine tools for on-machine measurement of ceramic structural parts.Moreover,the measuring rod portion can be transformed,and the measurement of the inner and outer profiles of the ceramic structural member by a single measuring machine is realized.The measuring range is expanded,and the problem that the deep cavity is difficult to measure is solved.Relying on the measurement prototype model,the finite element calculation software is used to optimize the critical dimensions of the key components of the measuring machine,and reduce the deformation of the measuring machine under static conditions.Meantime,using the Python programming language and the internal data structure of Abaqus software,the automatic script is written to establish the finite element input model.Realize automatic import of models,automatic submission of calculation tasks,automatic extraction of calculation result data,etc.Significantly save the time to establish the finite element model and calculate the data after processing,and based on the relevant calculation data to study the deformation of the measuring machine at different positions and at constant speed.Analyze the internal structure of the current common CNC system,rewrite the internal logic program of the CNC system,write the relevant NC program and perform external physical connection.Realize the control of the external signal on the Fanuc CNC system to the spindle movement of the machine tool.Using Python language and Py Qt software to write the upper computer graphical interface software,with the dynamic link library to call the internal function of the motion control card,to achieve the upper computer graphical interface control of the lower machine motion mechanism.Finally,using Isight software in conjunction with Abaqus software is proposed to optimize the force curve during the start-up process of the measuring machine.Write script files to achieve the integration of Isight software and Abaqus software;at the same time,use the restart technology of Abaqus software to realize the reuse of the calculation results and greatly shorten the time required for optimization.Determine the evaluation method of calculation results,and use the multi-island genetic algorithm to optimize the calculation to reduce the vibration of the cantilever part of the measuring machine during the starting process.