Resonant ferrofluidic inclinometers: New sensing strategies

In this paper a new architecture implementing a ferrofluidic inclinometer in resonant configuration is presented. The new strategy represents a considerable improvement with respect to previous devices , in this case resonance is exploited in order to improve the device sensitivity. In particular, the supplementary excitation coils have been positioned very close to the sensing tool (primary and secondary coils) in order to enhance their effect. Moreover, in order to further enhance the device sensitivity a new readout strategy which exploit a time based readout mechanism is used. It consists of a triggering circuitry which obtain a squared output signal which duty cycle is correlated to the imposed tilt. The new prototype implementation is reported together with simulation of the sensor behavior.