The Linewidth Detection And Control Study On Particle Feed Biological3D Print

The development of tissue engineering and biological manufacturing technology provides anew potential way to repair the damaged tissue in human body. The target tissue can be got with thehelp of culturing of cells on the scaffold, which is made into the shape of a target organ or tissue, bytechnology of tissue engineering. The normal way to make a scaffold is hard to achieve its functionbecause of the complex of the shape and structure. The rise of rapid prototyping technology is agood solution to the problem.The fused deposition modeling(FDM) among the RP technology has brought greatconvenience in making a biological scaffold. The scaffold can be designed with the help ofThree-dimensional modeling and use the polymeric biomaterials as the raw materials for fabricationof scaffolds. The process of making the scaffold is under the high or low conditions to make surethe scaffold has the best biological structure.The main feeding mode of FDM is to get the material in the shape of line. In this way, thedifferent shapes of raw materials should be further processed in the shape of uniform thickness lineswhich is not only wastes of raw materials but also poor efficiency. In order to make use of differentshapes of raw materials, the research group and Tsinghua University develop the experimentmachine of FDM which can use the materials in particle shape. This paper will go on studying theexperiment machine. After improvement of the feeding devices in the nozzle, the feeding of particlematerial is more steady and improve the forming speed. Besides, several results which are thereasons of FDM’ s low precision have been concluded after analyzing the working principle of theplatform, which is proved by the experiment between the scanning speed and the line width. Themain reason why the line width is not all the same in different conditions is nozzle’s extrudingspeed can’t be changed with scanning speed’s changing which may even destroy the scaffold. Afterresearching the mechanical structure of the platform, an intelligent control method which makesextruding speed change as the scanning speed changes is put forward that makes the whole processa semi closed loop control. The speed of the guide screw which is the power of the scanning speedcan be measured by photoelectric encoder and transmit the signal to the SCM to decide change thestepper motor driver which controls the extruding speed or not. Some good results have been gotafter transforming the experimental machine preliminarily. The extruding speed can changed withscanning speed and the line width of the contour curve is close to the line width of the internalfilling material, which can be understood that the difference of line width between different pathshas become smaller.