Research On On-machine Measurement And Conformal Accuracy Control Of 3D Printing Of Curved Surface Circuit

The curved surface circuit has the characteristics of conformal with the surface of the parts,which can save the space volume of the electronic products,and achieve the effect of lightweight,integration,structure and function integration.Electronic 3D printing technology enables rapid integrated manufacturing by depositing conductive functional materials directly on the surface of objects to form circuits.Its application to conformal printing of surface circuit can simplify the process flow,reduce the difficulty of preparation,and has a broad development prospect.However,how to improve the conformal quality of printing has always been a difficult problem in 3D printing of curved circuit.Therefore,this paper takes pneumatic direct writing electronic 3D printing technology as the research object,and researches the in-machine measurement and conformal accuracy control of 3D printing of curved circuit.The main contents are as follows:(1)Firstly,the key technology of pneumatic direct writing printing is discussed,and the influence of the working height of the print head on the print quality of the line is analyzed.It is found that the print head height will affect the material flow characteristics,and then affect the uniformity of the line width.The manufacturing error and positioning error of the parts will cause the working height error of the print head and affect the printing conformal accuracy.Based on this,an error compensation method of print head height is proposed,which is "error measurement on machine + line model reconstruction".(2)Based on the surface electronic circuit printing platform,an in-machine measurement system is built.The working principle of on-machine measurement is described,the hardware of on-machine measurement system and the pneumatic transmission control system are designed,and the probe control program is written.The system can directly measure the size of the part,improve the measurement efficiency and eliminate the repeated clamping error.(3)The error compensation of the working height of the print head is studied.Firstly,a curvature adaptive measuring point selection method is proposed to drive the measurement in the on-machine measuring system.Then,by reconstructing the real conductive circuit model and generating the print track of the real wire,the error compensation of the print head height is realized,and the printing conformal accuracy is improved.(4)A comparison experiment of wire printing before and after compensation was carried out.The results show that the on-machine measurement compensation method proposed in this paper can significantly improve the uniformity of the print line width,effectively solve the phenomenon of wire drawing and stacking,and enhance the electrical conductivity.Then,by printing the hemispherical lighting circuit and successfully lighting the LED light,the practicality of the improved direct write printing process was demonstrated.