Experimental Study On The Integrated Molding Of Blood Vessel-like Flow Channel Based On Pneumatic Extrusion And Piezoelectric Micro-jet

Tissue engineering based on biological three-dimensional printing technology provides a direction to solve the problem of artificial tissues and organs.However,the current tissue engineering is limited to thin tissues due to the lack of internal transportation channels for nutrients and wastes.How to build a set of molding system for manufacturing large tissue engineering with vascularized channels has become an urgent problem in biological 3D printing.With the support of the Provincial Natural Science Foundation of colleges and universities,in order to realize the integrated manufacturing of tissue engineering containing three-dimensional vascular channel,a biological three-dimensional printing device based on pneumatic extrusion and piezoelectric micro jet composite technology was designed,and the feasibility of the design was further verified by testing and experiments.The main research of this dissertation is as followsFirstly,an integrated molding method of composite process for 3D vascularized channels is proposed.On the basis of functional requirement analysis,various molding processes and their principles are analyzed and compared.A composite process based on pneumatic extrusion and piezoelectric micro jet is proposed,and a dual nozzle bioprinting molding system with composite process is designed.The three-axis motion frame is used as the mechanical frame,combined with the electrical control system and other modules to form a dual-nozzle bioprinting device,laying the foundation for the accurate and reliable operation of the device.Secondly,the hardware control circuit of the system is designed based on the concept of modularization.Modular design of the main control board of the hardware control circuit is mainly the core microprocessor module,power supply module,communication module and dual nozzle control module.Based on the research and development of the main board,the equipment selection and the connection of the overall hardware control circuit are mainly Three-dimensional motion module,dual-nozzle control module,motor drive module and host computer control module,etc.,realize the function of the composite process integration forming.Finally,complete the construction of biological 3D printing system,simulate and analyze the influence parameters of molding process,such as piezoelectric amplitude,frequency and material concentration,test the system performance through experiments,and compare and analyze the molding effect of different process parameters,so as to optimize the molding process parameters,such as printing speed,extrusion pressure and piezoelectric parameters.The feasibility of the model is proved by the simulation and the experiment of the composite process integration is carried out.The results show that the composite printing system can realize the integration of tissue engineering with custom-made vascular like channel,which is helpful for the subsequent culture of artificial thick tissue in vitro.The above meniscus model reconstruction and bioprinting experimental research based on composite manufacturing process has important theoretical support and reference value for complex tissue repair including bone and cartilage,and serves scientific guiding value.The established model is simulated,the theory proved its feasibility,and the composite process integrated molding experiment is carried out.The results show that the composite process printing system can realize the integrated formation of user-customized tissue engineering with vascularized channels,which is helpful for the subsequent in vitro culture of artificial thick tissues.