Angle Sensor Position Accuracy via Dual-Sensor Ratio
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing magnetic field sensors struggle to accurately determine the position of a rotating target with high precision and reliability, especially when faced with variations in the magnetic field and sensor placement tolerances.
Innovation Solution
A system comprising two magnetic field sensors with sensing elements having axes of sensitivity perpendicular to each other, positioned at different angles relative to a rotating target, and a controller that calculates the target's position based on differences between signals generated by each sensor.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Measurement precision
If a single magnetic field sensor is used to detect the position of a rotating target, then the device complexity is low, but the measurement precision and reliability are insufficient due to variations in magnetic field and sensor placement tolerances
Solution Approach 1:
The patent combines multiple magnetic field sensors (at least two sensors with perpendicular sensitivity axes) into a unified measurement system. Each sensor detects magnetic field components along orthogonal directions, and their signals are processed together through coordinate transformation to achieve accurate angular position measurement of the rotating target, resolving the contradiction between measurement precision and device complexity
Solution Approach 2:
The patent transitions from single-dimension magnetic field detection to multi-dimension detection by arranging sensors with perpendicular sensitivity axes. This orthogonal arrangement enables detection of magnetic field vector components in multiple dimensions, which are then transformed to calculate precise angular position, thereby improving measurement precision while maintaining manageable device complexity
2Reliability
If multiple magnetic field sensors are used to improve position detection accuracy, then the measurement precision improves, but the device complexity increases
Solution Approach 1:
The patent merges multiple sensor outputs into a unified position calculation system. By processing signals from sensors with perpendicular sensitivity axes through coordinate transformation and arctangent calculation, the system achieves reliable and redundant position detection, improving reliability while keeping the overall device complexity manageable through systematic signal processing
Solution Approach 2:
The patent changes the sensitivity axis orientation parameter of sensors to be perpendicular to each other. This specific parameter configuration enables the sensors to detect orthogonal components of the magnetic field vector, which when combined through mathematical processing, provides reliable position detection and reduces sensitivity to individual sensor placement variations
3Measurement precision
If sensors are positioned at different angles relative to the rotating target, then the accuracy of position determination improves, but the manufacturing precision requirements increase
Solution Approach 1:
The patent employs asymmetric sensor placement with perpendicular (90-degree) orientation between sensors rather than symmetric arrangements. This asymmetric orthogonal configuration creates a measurement system where the angular position can be calculated through coordinate transformation, making the system less sensitive to small placement variations and reducing manufacturing precision requirements while maintaining high measurement accuracy
Solution Approach 2:
The patent implements a feedback mechanism through mathematical processing where the outputs from multiple sensors are continuously processed through coordinate transformation and arctangent calculation. This feedback processing compensates for placement variations and magnetic field variations, improving angular position accuracy while reducing the stringency of manufacturing precision requirements
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 solution enhances the accuracy and reliability of determining the position of a rotating target by combining signals from multiple sensors, reducing errors associated with sensor placement and magnetic field variations.
Implementation Method 1
Magnetic field sensors including a magnetic field sensing element, or transducer, such as a Hall Effect element or a magnetoresistive element, are used in a variety of applications to detect aspects of movement of a ferromagnetic article
Implementation Method 2
Magnetic field sensors including a magnetic field sensing element, or transducer, such as a Hall Effect element or a magnetoresistive element
Data Source
AI summary
A method comprising: generating signals SA1 and SB1 by using a first sensor that is positioned at a first position relative to a rotating target, the signals SA1 and SB1 being generated in response to a magnetic field that is associated with the rotating target; generating signals SA2 and SB2 by using a second sensor that is positioned at a second position relative to the rotating target; and calculating a position of the rotating target based on a ratio of a first difference between the signals SA1 and SA2 and a second difference between the signals SB1 and SB2.