Compact peristaltic vacuum pumps via multi-material extrusion

Abstract

This study reports the design, fabrication, and characterization of the first 3D-printed peristaltic pumps for creating and maintaining dry vacuum in compact systems. The pumps implement a novel actuator design with a notched cross-section that requires less than half the force to fully seal, making it possible to create and maintain low vacuum at low actuation speed. The devices are made via multi-material extrusion: the rigid parts of the pumps are made in polylactic acid (PLA), while the compliant parts of the pumps are made in FiberFlex 40D—a relatively new flexible material that is easier to print than mainstream Ninjaflex, even though the two materials have similar hardness. A novel, analytical, reduced order model of a peristaltic vacuum pump is also presented to provide insights into its operation, while identifying the key parameters to optimize and improve its performance. Characterization of 3D-printed FiberFlex 40D demonstrates >105 cycles fatigue life, and its hyperelastic behavior is satisfactorily described by the Mooney Rivlin model. Experimental characterization of pump prototypes demonstrates the devices attain an order of magnitude lower base pressure than a state-of-the-art, single-stage, miniaturized diaphragm vacuum pump. The technology is of interest for in-situ, low-waste manufacturing of analytical hardware far from population centers, including in-space manufacturing and space colonization.