Measurement method of magnetic field for the wire suspended micro-pendulum accelerometer

• Published in: Sensors (Basel, Switzerland) Vol. 15; no. 4; pp. 8527 - 8539
• Main Authors: Lu, Yongle, Li, Leilei, Hu, Ning, Pan, Yingjun, Ren, Chunhua
• Format: Journal Article
• Language: English
• Published: Switzerland MDPI AG 13.04.2015; MDPI
• Subjects: Accelerometers; Accuracy; Algorithms; iterative least squares; magnetic field strength; Magnetic fields; Magnetization; Measurement methods; permanent magnet; Permanent magnets; Sensors; Temperature; Wire; Wire Suspended Micro-Pendulum Accelerometer; China
• ISSN: 1424-8220; 1424-8220
• DOI: 10.3390/s150408527

Force producer is one of the core components of a Wire Suspended Micro-Pendulum Accelerometer; and the stability of permanent magnet in the force producer determines the consistency of the acceleration sensor's scale factor. For an assembled accelerometer; direct measurement of magnetic field strength is not a feasible option; as the magnetometer probe cannot be laid inside the micro-space of the sensor. This paper proposed an indirect measurement method of the remnant magnetization of Micro-Pendulum Accelerometer. The measurement is based on the working principle of the accelerometer; using the current output at several different scenarios to resolve the remnant magnetization of the permanent magnet. Iterative Least Squares algorithm was used for the adjustment of the data due to nonlinearity of this problem. The calculated remnant magnetization was 1.035 T. Compared to the true value; the error was less than 0.001 T. The proposed method provides an effective theoretical guidance for measuring the magnetic field of the Wire Suspended Micro-Pendulum Accelerometer; correcting the scale factor and temperature influence coefficients; etc.