Pneumatic feeding system for low-temperature deposition manufacturing based on system identification

Low-temperature deposition manufacturing (LDM), which is based on the principles of additive manufacturing, can preserve biological activity by fabricating custom pore-sized three-dimensional (3D) scaffolds. Appropriate extrusion velocity is significant to the fabrication of ideal macro-porous structures, which prevents collapse between layers and over-accumulation of material. This paper: proposes a new pneumatic feeding system consisting of an air source and valves; focuses on combinations of mathematical delay models of the first order and least squares identification; and describes the construction of a model of pressure and extrusion velocity by analysing the process of pneumatic material feeding. Our tests confirmed the time series used to adjust the desired pressure via opening and closing valves to change the feeding velocity using the parameters of our model. Furthermore, we verified that gelatin scaffolds could be formed by LDM, and over-accumulation and decrease overlap had been solved to some extent using our time series.