The Intelligent Control Method Of Additive Manufacturing Flow Based On The Measurement Of The Line Width

Based on the technology of the Tissue engineering, the biological substance after a period oftime cultured in vitro can repair tissue or forming a new tissue or organ. Transplant the scaffold inthe body or in vitro can repair or replace some functions of the tissue or organ. The scaffold formedby the technology of tissue engineering and low temperature manufacturing can providesenvironment for the growth, proliferation and differentiation of the cells. Thus, the quality of thescaffold is important to repairing the tissue or organ.The advanced equipment-low temperature manufacture can form complex three-dimensionalscaffolds. Put the slurry of the biological scaffold into the hopper, the slurry ejected by the nozzle.According to the planed trajectory by the software, the nozzle piled into a three-dimensionalscaffold described by the data model. Consistent line width of the scaffold make the model orscaffold has good porosity and pore shape, so that it is contribute to the growth, proliferation anddifferentiation of the cells. So the research of the accuracy of the line width of the scaffold isimportant to the tissue engineering.The nozzle of the low-temperature manufacturing machine is open-loop control currently.When an error occurs during the forming process, it can not be adjusted and corrected in real time.Fracture due to the flow of the nozzle is too small or excessive deposition due to the speed of theslurry extruded by the nozzle is too fast reduced the accuracy and the surface quality of the scaffoldor entity. In conclusion, this paper proposed Based on the closed-loop control theory in the paper,an intelligent control method of additive manufacturing based on the measurement of the line widthis studied. The setpoint with the current line width which is scanned by the sensor is compared, therelative relationship between the displacement speed of the forming equipment’s workbench and therate of flow of the nozzle could be controlled. The focus of the closed-loop control is the collectionof the line width, three methods are proposed in the paper, a single camera measured the line widthof the slurry directly, a single camera measured the line width of the slurry combined with theimage procession and double cameras measured the line width of the slurry combined with theimage procession. According comparison, the third method as the feedback signal of theclosed-loop to complete the intelligent control can measure the ling width of the slurry in real timeand the arithmetic average error is0.013.