Chagas AM, Molloy JC, Prieto Godino LL, Baden T. Leveraging Open Hardware to Alleviate the Burden of COVID-19 on Global Health Systems. PLoS Biol pbio.3000730. direct link. (preprints.org version). pdf.
See also associated Nature Coronapod featuring co-author Jenny Molloy talking about this with Julie Gould (starting @22:55).