Magnetic Angle Sensor Stray Field Interference
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Magnetic angle sensors face challenges in accurately detecting the orientation of a magnet due to interference from stray magnetic fields, which can shift the zero-field line and affect the reliability of rotational angle measurements.
Innovation Solution
A magnetic angle sensor system comprising two sensor arrays and processing circuitry that identifies specific points on each array where the magnetic field components have predetermined values, allowing for the detection of the magnet's orientation based on these points and the distance between the arrays, thereby mitigating the impact of stray fields.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Measurement precision
If a single sensor array is used to detect magnetic field orientation, then the device complexity is low, but the measurement precision deteriorates due to stray magnetic field interference
Solution Approach 1:
The sensor system is divided into multiple sensor arrays (first sensor array and second sensor array) with sensor elements arranged along different lines. Each array independently detects magnetic field components, and their results are combined to determine the zero-field line orientation, thereby improving measurement precision while managing device complexity through modular segmentation
Solution Approach 2:
The patent transitions from a single-line sensor arrangement to a multi-line multi-dimensional sensor configuration. By arranging sensor elements along multiple lines in different orientations, the system captures magnetic field information from multiple dimensions, enabling more accurate determination of the zero-field line orientation and magnet orientation
2Measurement precision
If sensor elements are arranged densely to improve measurement precision, then the orientation detection accuracy improves, but the manufacturing precision requirements increase
Solution Approach 1:
The sensor system uses multiple sensor arrays with elements arranged along different lines rather than requiring extremely dense single-line arrangements. This segmentation approach allows for more relaxed manufacturing tolerances while maintaining measurement precision through the combined information from multiple arrays
Solution Approach 2:
The patent changes the spatial arrangement parameters of sensor elements by distributing them across multiple lines and arrays rather than concentrating them in a single dense array. This parameter change in the geometric configuration reduces the stringency of manufacturing precision requirements while preserving the ability to accurately detect orientation through multi-point measurements
Applied Scientific Principles
This section explains which scientific principles are used to turn an abstract innovation direction into a practical engineering solution.
Function Achieved in This Case
The system provides reliable and accurate detection of the magnet's orientation by using the identified points to calculate the rotational angle, ensuring robustness against stray magnetic field interference.
Implementation Method 1
detect a magnetic field produced by the magnet by using the first sensor array
Data Source
AI summary
A sensor is disclosed for detecting an orientation of a magnet, the sensor comprising: a first sensor array including a first plurality of sensor elements that are arranged along a first line; a second sensor array including a second plurality of sensor elements that are arranged along a second line; and a processing circuitry configured to: detect a magnetic field produced by the magnet by using the first sensor array, and identify a first point on the first line where at least one component of the magnetic field has a predetermined value; detect the magnetic field by using the second sensor array, and identify a second point on the second line where at least one component of the magnetic field has the predetermined value; detect an orientation of the magnet relative to the sensor based on the first point and the second point; and output an indication of the orientation of the magnet based on the first point and the second point.