Magnetic Position Sensing with Gradient-Based Fault Detection
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Magnetic position sensor systems struggle to accurately determine position and integrity in harsh environments with electromagnetic disturbances, while also detecting mechanical and electrical faults without increasing processing power or complexity.
Innovation Solution
A magnetic position sensor system that uses at least three magnetic sensitive elements to measure magnetic field values, gradients, and differences to derive both position and fault signals, utilizing polynomial expressions of these gradients to provide fault detection insensitive to external disturbances.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If magnetic position sensor systems use traditional measurement methods, then they can determine position, but they cannot reliably detect faults or integrity issues in harsh environments with electromagnetic disturbances
Solution Approach 1:
The patent segments the measurement function into two independent signal derivation paths: one for position determination and another for fault detection. By using separate signal processing channels that both rely on magnetic field gradients, the system can independently verify integrity without adding complex hardware, thus improving reliability while maintaining manageable complexity
Solution Approach 2:
The patent introduces magnetic field gradients as an intermediary parameter that serves dual purposes: enabling position measurement and providing fault detection capability. This intermediary approach allows the system to extract multiple pieces of information from the same magnetic field measurements without requiring additional sensors or complex processing architecture
2Measurement precision
If the system derives position from magnetic field values, then position can be determined, but the measurement becomes sensitive to external disturbance fields
Solution Approach 1:
The patent changes the measurement parameter from absolute magnetic field values to magnetic field gradients (spatial derivatives). This parameter transformation makes the measurement inherently more robust against external disturbance fields, as gradients represent local field variations that are less affected by uniform external interference, thereby improving measurement precision while reducing sensitivity to harmful factors
3Reliability
If the system provides both position and fault detection signals, then system safety is enhanced, but processing power requirements increase
Solution Approach 1:
The patent implements multi-functionality by deriving both position and fault detection signals from the same magnetic field gradient measurements using polynomial expressions. This universal approach allows a single measurement set to serve multiple purposes, enhancing system safety while minimizing additional processing power requirements compared to separate dedicated systems
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 effectively determines position and detects faults, such as mechanical and electrical issues, in harsh environments, enhancing system safety and reducing processing requirements.
Implementation Method 1
at least three magnetic sensitive elements for measuring at least three magnetic field values of said magnetic field
Data Source
AI summary
A position sensor system includes a magnetic source for generating a magnetic field, and a position sensor device movable relative to the magnetic source, or vice versa. The position sensor device comprises at least three magnetic sensor elements for measuring at least three magnetic field values of the magnetic field, and a processing circuit configured for determining at least two magnetic field gradients or magnetic field differences based on the at least three magnetic field values, and for deriving from the at least two magnetic field gradients or differences a first value indicative of a position of the position sensor device, and for deriving from the at least two magnetic field gradients or differences a second value indicative of integrity of the position sensor system.