Large-size Light Projection 3D Printing System For The Internet Of Things

Digital light projection(DLP)3D printing technology is based on the principle of rapid curing of liquid photosensitive resin under ultraviolet radiation to realize arbitrary molding by accumulating a two-dimensional resin cured layer.It stands out among other3D processing technologies due to its advantages in precision and efficiency,but it is limited by the molding area so that is mainly used for precise manufacturing and small-scale molding.This paper proposes a large-size turntable 3D printing method based on rotating splicing,In-depth research on the design of rotation stitching algorithm,image segmentation in polar coordinates,and 3D printing control system.The main contents are as follows:(1)For the problem of the small size of the parts processed by DLP 3D printing technology,a solution is proposed to expand the molding area by rotating and moving the digital projector.Compared with other large-size printing methods,this method makes the whole machine lower in cost,simpler in mechanical structure,and more convenient in installation and maintenance while ensuring the molding accuracy.(2)Focusing on the requirements of rotary stitching for sliced images,this paper focuses on the research of slice image segmentation algorithm oriented to rotary stitching--adaptive image segmentation algorithm.That is,according to the position of the effective region in the slice image,the image segmentation position can be adjusted adaptively.Compared with another image segmentation algorithm with constant number and fixed position,this algorithm further reduces the number of image segmentation,avoids repeated exposure of the effective area,and effectively improves the printing efficiency and quality.(3)Aiming at the needs of convenient remote printing and other IoT applications,this paper designed a remote printing control system based on the cooperation of Raspberry Pi and STM32.That is,on the basis of completing the control of large-scale 3D printing,a DLP 3D Internet of Things printing platform with convenient operation,rich functions and easy expansion is built.(4)Test and verification of adaptive image segmentation algorithm and rotation stitching 3D printing molding.Firstly,the adaptive image segmentation algorithm is compiled on multiple platforms,and the image rotation and stitching effect after segmentation is simulated according to the segmentation results,which verifies the effectiveness of the algorithm.Secondly,a turntable printing platform was integrated in the printer system,and several single-layer rotating solidification splicing experiments were completed to verify the feasibility of the scheme,and at the same time,the error analysis of the experimental results was carried out.