A7.1 - Multiturn and high precision through-shaft magnetic sensors
- SENSOR+TEST Conferences 2009
2009-05-26 - 2009-05-28
Congress Center Nürnberg
- Proceedings SENSOR 2009, Volume II
- A7 - Magnetic Sensors II
- G. Masson, Y. Ronnat, T. Dorge, S. Biwersi - Moving Magnet Technologies SA, Besançon, France
- 41 - 46
Magnetic sensors have several advantages which make them attractive for automotive applications: they are contactless (there is no mechanical wear-out), insensitive to dirt and are relatively simple. MMT formerly developed a 360° through shaft angular position sensor technology using a probe which measures the magnetic field angle variation generated by a rotary diametrically magnetized magnet. Now, MMT is focusing on derived designs providing additional features like a multi-turn output, an improved accuracy or a very low sensitivity to external magnetic fields.
One of the targets is to meet the standard requirements for the automotive steering applications (the Electronic Stability Program legislation being one of the key drivers), and especially an accuracy of +/- 1° or below. An other aim is to provide an absolute multi-turn output in a compact embodiment.
In this paper, after presenting the basics of our 360° through shaft solution we will introduce a generic principle to improve the sensor linearity and provide prototype measurement results. Then, we will present absolute multi-turn sensor concepts including again prototype design and measurement results.