Optimization and Long-Term Stability of Micro Flow Sensors for Smart VP Shunts
AffiliationUniv Arizona, Dept Aerosp & Mech Engn
Univ Arizona, Dept Surg
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CitationG. Édes, E. T. Enikov, J. Skoch and R. Anton, "Optimization and Long-Term Stability of Micro Flow Sensors for Smart VP Shunts," in IEEE Sensors Journal, vol. 20, no. 15, pp. 8455-8462, 1 Aug.1, 2020, doi: 10.1109/JSEN.2020.2984781.
JournalIEEE SENSORS JOURNAL
Rights© 2020 IEEE.
Collection InformationThis item from the UA Faculty Publications collection is made available by the University of Arizona with support from the University of Arizona Libraries. If you have questions, please contact us at firstname.lastname@example.org.
AbstractThis paper reports on a systematic study of the flow sensitivity and resolution of micro-flow sensors intended for use in implantable ventricular-peritoneal shunts. The flow sensors utilize ferromagnetic flaps (transducers) whose deflection is detected by ultra-sensitive MTJ sensors (20mV/V/Oe). A working range of 0-40 ml/h was demonstrated at a maximum uncertainty of 4% RMS and a resolution of 0.4 ml/h. Earlier studies on this sensor unveiled significant low-frequency noise (drift) limiting the sensitivity to 1.4 ml/hr. The present study identifies thermal noise as the main source of low-frequency drift. Using thermal compensation it was found that the drift can be reduced below 2 ml per 24-hr. Combining an array of four transducers operating in series, it has been demonstrated that a sensitivity can be increased 10.9 fold. Furthermore, the report examines the long-term structural stability of the sensors and produces a corrosion report suggesting a lifespan of 15 to 55 years.
VersionFinal accepted manuscript
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