AUTHOR=Pedro Bruna Gabriela , Bertemes-Filho Pedro 

TITLE=A New Impedance Sensor Based on Electronically Implemented Chaotic Coupled van der Pol and Damped Duffing Oscillators

JOURNAL=Frontiers in Electronics

VOLUME=Volume 3 - 2022

YEAR=2022

URL=https://www.frontiersin.org/journals/electronics/articles/10.3389/felec.2022.797525

DOI=10.3389/felec.2022.797525

ISSN=2673-5857

ABSTRACT=The signature of chaotic systems can be characterized either by the sensitivity of the initial conditions or by the change of its parameters. This feature can be used for manufacturing high sensitivity sensors. Sensors based on chaotic circuits have already been used for measuring water salinity, inductive effects, and both noise and weak signals. This article investigates an impedance sensor based on the Van der Pol and Duffing damped oscillators. The calibration process is a key point and therefore the folding behavior of signal periods was also explored. A sensitivity of 0.15 kΩ /Period was estimated over a range from 89.5 to 91.6 kΩ. This range can be adjusted according to the application by varying the gain of the operational amplifier used in this implementation. The development of this type of sensor might be used in medical and biological engineering for skin impedance measurements, for example. This type of chaotic sensor has the advantage of sensing small disturbances and then detect small impedance changes within biological materials which, in turn, may not be possible with other detectors.