3D Printable Smart Masks and Nose Plugs

Common masks have equal filtering efficiency in exhalation and inhalation processes. The masks trap COVID-19 viral aerosols, but waste space for trapping non-viral aerosols and make breathing difficult when fresh, clean air flows through. For patients, it is important to have high virus trapping efficiency when they exhale to prevent onward transmission and allow smooth air intake when they inhale.

The objective of the project is to develop 3D printable smart masks and nose plugs to prevent onward transmission of coronavirus from patients. The masks and nose plugs have an array of channels, curved micropillars in each channel, and small reservoirs of medical disinfectant housed between pillars. The smartness derives from the designed curved micropillars, whose curvatures will change in response to people’s respiratory.

During exhalation, the micropillars stretch to form a narrow air flow path while trapping viral aerosols from patients and releasing disinfectants to kill the viruses. During inhalation, micropillars bend downward to prevent the release of disinfectant, bring coronavirus into disinfectant, and allow smooth airflow for an easy inhale.

In this project, we performed structural designs and numerical simulations to validate and optimize our designs and 3D printed the products. We estimate an 18.7 times higher trapping efficiency in exhalation than that in inhalation. Designs, analysis, and prototyped products can be found in our uploaded PowerPoint file in Schematic section. CAD files are provided for rapid, low-cost, and customizable 3D printing of masks and nose plugs.

Bill of Materials:

1. Printing materials (Elastic resin from Formlabs or equivalent)

$199 for 1L (can print 120 masks and 1600 nose plugs)

2. Medical disinfectant (optional, Food & Lab Grade Ethanol or equivalent)

$18.5 for 1 quart (enough for 1000 masks and nose plugs)

Instructions

1. Given CAD files, upload to 3D printer and/or software

2. If necessary, personalize the dimensions of the products for better fit for user

3. 3D printing

4. Dip in or spray disinfectant on external surface if applicable

5. Wear mask and nose plugs properly