Hall Sensor Displacement Measurement Interference Compensation
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing displacement measuring arrangements using Hall sensors are prone to magnetic field interference, which complicates accurate measurement of displacement or position.
Innovation Solution
The implementation of a second Hall sensor with a perpendicular measurement direction to the first Hall sensor, allowing for the detection and compensation of interfering magnetic fields, while ensuring the magnetic field generated by the magnet is not detected by the second sensor.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Measurement precision
If a Hall sensor is used to measure displacement, then displacement or position can be detected, but magnetic field interference from external sources distorts the measurement signal
Solution Approach 1:
A second Hall sensor is introduced as an intermediary element to detect the interference magnetic field. This intermediary sensor allows the system to identify and compensate for external magnetic field disturbances by measuring the interference component separately, which is then subtracted from the first sensor's signal to recover the true displacement measurement.
Solution Approach 2:
The system implements feedback by using the second Hall sensor to continuously monitor the interference magnetic field and feeding this information back to the evaluation unit. The evaluation unit then adjusts the first sensor's output signal by subtracting the interference component, creating a closed-loop compensation mechanism that improves measurement accuracy.
2Reliability
If a second Hall sensor is added to detect interference fields, then compensation for magnetic field interference becomes possible, but the device complexity increases
Solution Approach 1:
The second Hall sensor is oriented with its measurement direction perpendicular to that of the first sensor. This dimensional change in sensor orientation allows the second sensor to selectively detect only the interference magnetic field component while being insensitive to the magnetic field generated by the magnet for displacement measurement, enabling interference compensation without affecting the primary measurement function.
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
This configuration enables accurate compensation of interference fields, resulting in a signal that accurately indicates the displacement or position, thereby improving the reliability of displacement measurements.
Implementation Method 1
a first Hall sensor (3a) and a magnet (2), wherein the first Hall sensor (3a) has a first measurement direction (z) in which a component of a magnetic flux density can be measured with the first Hall sensor (3a)
Implementation Method 2
the displacement measuring arrangement has a second Hall sensor (3b), the second Hall sensor having a second measurement direction (y) in which a component of a magnetic flux density is measurable with the second Hall sensor (3b)
Implementation Method 3
A movement d of magnet 2 relative to Hall sensor 3 changes the magnetic field produced by magnet 2 at the location of Hall sensor 3
Data Source
Figure 1~2
AI summary
The invention concerns a displacement measuring arrangement with a first Hall sensor (3a) and a magnet (2), said first Hall sensor (3a) having a first measurement direction (z) in which a component of a magnetic flux density is measurable with said first Hall sensor (3a), the first Hall sensor (3a) and the magnet (2) being arranged such that relative movement is possible between the first Hall sensor (3a) and the magnet (2), wherein the magnetic flux density of the magnet (2) in the first Hall sensor (3a) is at least substantially in the direction of the first measurement direction (z), the displacement measuring device comprising a second Hall sensor (3b), the second Hall sensor (3b) having a second measurement direction (z) in which a component of a magnetic flux density can be measured with the second Hall sensor (3b), wherein the first Hall sensor (3a) and the second Hall sensor (3b) are arranged such that the first measurement direction (z) and the second measurement direction (z) are at least substantially parallel, wherein the second Hall sensor (3b) and the magnet (2) are arranged such that the magnetic flux density of the magnet (2) in the second Hall sensor (3b) is at least substantially perpendicular to the second measurement direction.