Research on planar magnetic induction angle sensor based on m-sequence coding

The planar magnetic induction angle sensor made by PCB process is more resistant to impact and vibration than the traditional photoelectric encoder, but the absolute position coding method nonius coding is not easy to realize in the high-precision sensing unit. There are a great many pole pairs of high-precision sensing units, resulting in a small error correction range of cursor coding and easy angle jump, so there are high requirements for the installation of sensors. To solve the above problems, a planar magnetic induction angle sensor based on m-sequence coding is studied in this paper. The coarse code channel of the sensor adopts differential m-sequence coding, which effectively improves the absolute coding error correction range of the sensor. The actual measurement of the prototype shows that the sensor can realize reliable absolute position measurement under loose installation conditions, and the measurement accuracy is ± 10 "in the range of 0 ~ 360°.This coding method not only improves the error correction range of the sensor, but also provides a new idea for the coding method of planar magnetic induction angle sensor.