Research on the linearity of a magnetic fluid micro-pressure sensor

A new type of micro-pressure sensor using a magnetic fluid drop with permanent magnets fixed at ends of an iron core as a sensitive element is investigated in this paper. Movement of the sensitive element inside the body with the variation of external pressure will lead to a corresponding inductance difference. The sensor supplies a signal which is proportional to the displacement of sensitive element. The determination of the working range, linearity and sensitivity depends on the tilt angle and the magnetic repulsion force. An experiment is performed to analyze the influence of different tilt angle on the linearity and sensitivity. Some characteristics of the sensor are presented.