Optimization and Long-Term Stability of Micro Flow Sensors for Smart VP Shunts
Affiliation
Univ Arizona, Dept Aerosp & Mech EngnUniv Arizona, Dept Surg
Issue Date
2020-08-01Keywords
Temperature sensorsMagnetic sensors
Sensitivity
Transducers
Magnetic tunneling
VP shunt
flow sensor
thermal noise
MEMS
MTJ sensor
Metadata
Show full item recordCitation
G. 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.Journal
IEEE SENSORS JOURNALRights
© 2020 IEEE.Collection Information
This 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 repository@u.library.arizona.edu.Abstract
This 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.ISSN
1530-437XEISSN
2379-9153Version
Final accepted manuscriptScopus Count
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