A ferrofluid inclinometer with a Time Domain Readout strategy

Abstract

In this paper a tilt sensor exploiting the effect of the imposed tilt on a ferrofluid drop free to move inside a glass channel is presented. The proposed inclinometer consists of a 10 mm diameter pipe containing a 0.25 ml of ferrofluid, an actuation coil to control the ferrofluid mass movement and two sensing coils to monitor the mass position. The actuation and the sensing coils are wound around the pipe and the length of the actuation/sensing system is 78 mm. The novelty of this device, as respect to solutions already presented in the literature, consists in the conversion of the device tilt into the time elapsed between transitions of the ferrofluid mass in two fixed positions inside the channel. This time domain readout strategy allows to implement a digital form of the device output which can be intended as the main advantage of the solution proposed.

Ferrofluids: Synthetic Strategies, Stabilization, Physicochemical Features, Characterization, and Applications

“…[327] Ferrofluid sensing applications in accelerometers, flow meters, inclinometers, vibration/pressure sensors, and switches are being researched widely owing to their enhanced motion sensitivity. [328] Their utility for magnetic domain detection and domain structure studies in magnetic tapes, garnets, steels, alloys, magneto-optical disks, and photoresist is also significant. [329] In solenoids, the use of FFs can dramatically reduce the noise level leading to quieter operation with convenient portability.…”

Design analysis of electromagnetic actuator with ferrofluid

“…Furthermore, a significant problem associated with solenoid type actuators is related to the magnetic flux leakage. The ferrofluid substantially reduces the magnetic flux leakage in magnetic circuit of the actuator [2][3][4][5][6][7][8][9][10][11].…”

Use of Magnetic Fluid in Accelerometers

“…In recent years, the magnetic fluid accelerometers have been further improved. The research team from Italy have designed a series of magnetic fluid accelerometers with good performance [7][8][9][10][11][12]. Li et al studied the dynamical characteristics of a ferrofluid accelerometer [13,14].…”