A MEMS-based passive air flow regulator for handheld breath diagnostics
2014 (English)In: Sensors and Actuators A-Physical, ISSN 0924-4247, Vol. 215, 65-70 p.Article in journal (Refereed) Published
This paper reports on a passive MEMS-based flow regulator designed to maintain a steady flow during asthma diagnostics. A prototype consisting of six in-plane moving pistons that restrict the flow through six flow orifices has been fabricated from three wafers using standard silicon micromachining. The in-plane design enables relatively large flows and tuning of the flow and pressure range to specific application requirements by changing a wafer thickness. In particular, for FENO asthma monitoring, regulatory guidelines specifies that measurements should be made at steady flow of approximately 50 ml/s and within a pressure range of 1–2 kPa. Experimental evaluation of the prototype shows that the flow rate is controlled within a dynamic pressure range of 770 Pa compared to only 430 Pa for a dummy structure and that it can be achieved on a chip measuring only 2 mm × 2 mm × 4 mm. The evaluation also showed that condensation of exhaled air that expectedly occurs in the flow regulator at room temperature can be eliminated by local heating of the device to 40◦C.
Place, publisher, year, edition, pages
Elsevier, 2014. Vol. 215, 65-70 p.
Flow regulator, passive, breath diagnostics, asthma, FENO, large flow
Medical Biotechnology Other Electrical Engineering, Electronic Engineering, Information Engineering
IdentifiersURN: urn:nbn:se:kth:diva-133217DOI: 10.1016/j.sna.2013.09.012ISI: 000339129800010ScopusID: 2-s2.0-84903313396OAI: oai:DiVA.org:kth-133217DiVA: diva2:660245
QC 201408192013-10-292013-10-292014-08-19Bibliographically approved