Magnetic Position Sensor Error Detection via Ratio Diagnostics
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Magnetic position sensor systems lack effective error detection capabilities, often requiring trade-offs between accuracy, robustness against external disturbances, and cost, with existing systems not being able to reliably detect errors without increasing the number of sensor elements or footprint.
Innovation Solution
A magnetic position sensor system utilizing a substrate with two or more magnetic sensors capable of measuring orthogonal magnetic field components, processing circuits to calculate differences and ratios of these components, and outputting diagnostic signals for error detection, which is robust against external disturbances and maintains accuracy without doubling the number of sensor elements.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If error detection capabilities are added to magnetic position sensor systems, then reliability is improved, but device complexity increases
Solution Approach 1:
The existing magnetic sensors are made multi-functional by having them perform both position measurement and error detection. The same sensor elements that measure position are also used to generate diagnostic signals through ratio calculations, eliminating the need for separate error detection hardware and reducing overall device complexity while improving reliability
Solution Approach 2:
A feedback mechanism is implemented where the sensor system continuously monitors its own operational status by comparing ratio values from different sensor combinations. When discrepancies exceed predefined thresholds, the system generates diagnostic signals indicating potential errors, enabling real-time self-diagnosis and improving reliability without adding complex external monitoring systems
2Reliability
If the number of sensor elements is increased to improve error detection, then reliability is improved, but the footprint of sensor elements increases
Solution Approach 1:
Existing sensor elements are made multi-functional to perform both position measurement and error detection simultaneously. By using the same sensors for dual purposes and implementing mathematical ratio comparisons, the system achieves error detection capability without adding more physical sensor elements, thus maintaining a compact footprint while improving reliability
Solution Approach 2:
The error detection function is merged with the position measurement function by using identical sensor elements for both purposes. The processing circuit combines position measurement data with diagnostic ratio calculations in an integrated manner, eliminating the need for separate error detection sensor arrays and reducing overall sensor footprint
3Object-affected harmful factors
If robustness against external disturbance fields is improved, then measurement precision is maintained, but device complexity increases
Solution Approach 1:
The system converts the effect of external disturbance fields into a diagnostic tool by monitoring ratio inconsistencies. When external fields affect the sensors, they create detectable deviations in the expected ratio relationships. By treating these disturbance-induced variations as diagnostic signals rather than mere noise, the system achieves robustness against external disturbances while using relatively simple ratio comparison processing
Solution Approach 2:
A feedback mechanism continuously monitors ratio values to detect deviations caused by external disturbance fields. When ratio discrepancies exceed predefined thresholds, the system generates diagnostic signals indicating potential interference or errors. This feedback approach maintains measurement precision under external disturbances while using straightforward threshold-based processing rather than complex algorithms
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
Enables accurate position determination and error detection in a system that is highly insensitive to external disturbance fields, maintaining accuracy and reducing the footprint of sensor elements, thus improving robustness and efficiency.
Implementation Method 1
each magnetic sensor capable of measuring three orthogonal magnetic field components (e.g. Bx, By, Bz)
Data Source
Figure 1~2A
Figure 2B~2C
Figure 3~4
AI summary
A position sensor device comprising two or more magnetic sensors (S1, S2) capable of measuring one or two or three orthogonal magnetic field components (Bx, By, Bz) at various sensor locations; and a processing circuit for determining a first, a second and a third difference (ΔBx12, ΔBz12, ΔBy12) of two respective components, and for determining a first ratio (R1) of the first and second difference (ΔB×12, ΔBz12), and determining and outputting a first angle (θmain) based on this first ratio (R1); and for determining a second ratio (R2) of the first and third difference (ΔBx12, ΔBy12), for optionally determining a second angle (θaux), optionally comparing the two angles or the two ratios; and for outputting at least one of: the second angle, the two ratios, a diagnostic signal based on a comparison of the angles or ratios.