Position sensor system and method, robust against disturbance field

Patent metadata

Field	Value
Publication number	US-11143527-B2
Application number	US-201916453321-A
Country	US
Kind code	B2
Filing date	Jun 26, 2019
Priority date	Jun 26, 2018
Publication date	Oct 12, 2021
Grant date	Oct 12, 2021

Abstract

A position sensor system comprising: a magnetic field generator movable relative to two sensor devices or vice versa. The system has at least one processor adapted with a special algorithm for determining a position of the magnetic field generator in a manner which is highly robust against a disturbance field. A method for determining the position of the magnetic field generator based on a set of equations, in particular a set of linear equations which allows to completely eliminate the external disturbance field.

First claim

The invention claimed is:

1. A position sensor system comprising:
a magnetic field generator movable relative to a first and a second sensor device or vice versa, and being adapted for providing a first magnetic field vector to the first magnetic sensor device and for providing a second magnetic field vector different from the first magnetic field vector, to the second magnetic sensor device;
the first sensor device being adapted for determining first vector data related to a combination of said first magnetic field vector and an external disturbance field, if present;
the second sensor device being adapted for determining second vector data related to a combination of said second magnetic field vector and said external disturbance field, if present;
the position sensor system further comprising at least one processor adapted for receiving the first vector data and the second vector data, and adapted for performing a method of determining a position of the magnetic field generator relative to the first and second sensor, which is based on the first vector data and the second vector data in a manner which eliminates the external disturbance field;
wherein the position sensor system is a linear position sensor system; and
wherein the position is a linear position; and
wherein the magnetic field generator is movable along a longitudinal axis, or wherein the first and second sensor are movable along a longitudinal axis; and
wherein the first and second magnetic sensor device have a predefined first and second position and a predefined first and second orientation relative to said longitudinal axis.

2. A position sensor system comprising:
a magnetic field generator movable relative to a first and a second sensor device or vice versa, and being adapted for providing a first magnetic field vector to the first magnetic sensor device and for providing a second magnetic field vector different from the first magnetic field vector, to the second magnetic sensor device;
the first sensor device being adapted for determining first vector data related to a combination of said first magnetic field vector and an external disturbance field, if present;
the second sensor device being adapted for determining second vector data related to a combination of said second magnetic field vector and said external disturbance field, if present;
the position sensor system further comprising at least one processor adapted for receiving the first vector data and the second vector data, and adapted for performing a method of determining a position of the magnetic field generator relative to the first and second sensor, which is based on the first vector data and the second vector data in a manner which eliminates the external disturbance field;
wherein the first sensor device comprises a first substrate defining a first plane; and
wherein the second sensor device comprises a second substrate defining a second plane; and
wherein the first plane and the second plane are substantially perpendicular.

3. A position sensor system comprising:
a magnetic field generator movable relative to a first and a second sensor device or vice versa, and being adapted for providing a first magnetic field vector to the first magnetic sensor device and for providing a second magnetic field vector different from the first magnetic field vector, to the second magnetic sensor device;
the first sensor device being adapted for determining first vector data related to a combination of said first magnetic field vector and an external disturbance field, if present;
the second sensor device being adapted for determining second vector data related to a combination of said second magnetic field vector and said external disturbance field, if present;
the position sensor system further comprising at least one processor adapted for receiving the first vector data and the second vector data, and adapted for performing a method of determining a position of the magnetic field generator relative to the first and second sensor, which is based on the first vector data and the second vector data in a manner which eliminates the external disturbance field;
wherein the first sensor device has a first local coordinate system; and
wherein the second sensor device has a second local coordinate system; and
wherein none of the axes of the first coordinate system is parallel to any of the axes of the second coordinate system.

4. A position sensor system comprising:
a magnetic field generator movable relative to a first and a second sensor device or vice versa, and being adapted for providing a first magnetic field vector to the first magnetic sensor device and for providing a second magnetic field vector different from the first magnetic field vector, to the second magnetic sensor device;
the first sensor device being adapted for determining first vector data related to a combination of said first magnetic field vector and an external disturbance field, if present;
the second sensor device being adapted for determining second vector data related to a combination of said second magnetic field vector and said external disturbance field, if present;
the position sensor system further comprising at least one processor adapted for receiving the first vector data and the second vector data, and adapted for performing a method of determining a position of the magnetic field generator relative to the first and second sensor, which is based on the first vector data and the second vector data in a manner which eliminates the external disturbance field;
wherein the first sensor device comprises a first substrate defining a first plane; and
wherein the second sensor device comprises a second substrate defining a second plane; and
wherein the first plane and the second plane are substantially parallel; and
wherein a first projection of the first magnetic field vector in the first plane is anti-parallel to a second projection of the second magnetic field vector in the second plane; and
wherein said determining a position of the magnetic field generator comprises calculating the position based on the following set of formulas or an equivalent set of formulas:

{

B
⁢

⁢
1
⁢
magx

=

(

v
⁢

⁢
1
⁢
x

-

v
⁢

⁢
2
⁢
x

)

Assignees

• Melexis Tech Sa

Inventors

• Bilbao De Mendizabal Javier

Classifications

• G01D5/145

  influenced by the relative movement between the Hall device and magnetic fields (see G01R33/06) · CPC title

• G01D3/028 Primary

  mitigating undesired influences, e.g. temperature, pressure · CPC title

• G01D5/245 Primary

  using a variable number of pulses in a train · CPC title

• G01B7/30

  for measuring angles or tapers; for testing the alignment of axes · CPC title

• G01B7/003 Primary

  for measuring position, not involving coordinate determination (coordinate measuring G01B7/004) · CPC title