2024 年 8 巻 1 号 p. 30-34
We propose a novel strain sensor utilizing an orthogonal fluxgate sensor system with bulk materials. Instead of a magnetic field, strain is applied to an orthogonal fluxgate magnetic field sensor to produce an output. In this study, verification experiments were conducted to validate that the sensor works according to its principle. We also explored operational conditions to enhance sensitivity. Furthermore, to confirm the effectiveness of the orthogonal fluxgate system as a strain sensor using bulk materials, we compared it with the magneto impedance system. Results confirmed the functionality of the orthogonal fluxgate system, as evidenced by the observation of magnetic domains under stress and strain-output characteristics at a frequency of 250 kHz. The peak sensitivity reached 6.72 mV/ppm with a bias magnetic field of 2 Oe and a carrier frequency of 250 kHz. When compared with the magneto impedance system, there was a 87-fold difference in sensitivity, indicating potential as a highly sensitive strain sensor.
