A resonant microcantilever sensor for in-plane multi-axis magnetic field measurements

A novel magnetic field sensor is developed based on the microcantilever resonator to realize the parameter measurements of in-plane multi-axis magnetic field under different vibration modes. The working equations of the resonant sensor are established to calculate the strength and direction angle of measured magnetic field based on different resonances. The strength components of magnetic field along x-axis and y-axis are independently measured by the proposed resonant sensor under flexural and torsional resonant modes, respectively. The corresponding outputs of the sensor are linearly related to the magnetic field strength components. The finite element simulations are performed not only to prove the capability of the sensor to measure magnetic field under different modes, but also indicate the mode coupling of microcantilever resonator existed in the measurement. Thus, the coupling compensation method is proposed by amending ouput voltage of the sensor through experiments. The experimental results at atmospheric pressure show that the compensated accuracies of in-plane magnetic field are 3.06% (strength) and 1.59% (angle), and the measuring sensitivities are 98.79 mu V mT(-1) along x-axis and 92.46 mu V mT(-1) along y-axis, respectively.