This paper developed a multi-nozzle pneumatic extrusion-based additive manufacturing (AM) system and applied it to print multi-material polymers and conductive sensing pads. We used pneumatic extrusion nozzles to extrude the liquid material and then cured it by an ultraviolet (UV) light source. The multi-nozzle pneumatic extrusion-based additive manufacturing system mainly integrates both PC-based HMI and CNC controller to operate the three-axis motion and the extrusion flow control. Moreover, the peripheral I/Os include both positive and negative pressure and also the curing light source. A D/A controller is also applied to control the value of the pneumatic pressure. The coding part utilizes the numerical control software along with the PLC planning to operate the AM machine automatically. Our experiment is conducted by using Simplify3D, a commercial 3D printing slicing software. Different requirements were set for extrusion nozzles with different materials, and then we executed the path controlling G-code data by Python Language. Our system successfully prints multi-material polymer structure pads which include the hard and soft material pad fabricated in double-layers, triple-layers and also the grid structure. Finally, we find that the printed pad has conductivity.
Optimization of UV light source conditions for photocatalytic activity of methyl orange using TiO2
