Position Sensor Assembly Temperature Compensation
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Current position sensors, such as RVDTs and resolvers, face challenges in providing reliable and accurate angular displacement measurements, especially in critical applications like aircraft, due to inherent non-linearity and temperature variations, which affect the accuracy of the output signals.
Innovation Solution
A fully integrated position sensor assembly that includes a housing with a stator and a moving element, primary and secondary windings, signal conditioning electronics with an integrated circuit for excitation and demodulation, and a temperature sensor to compensate for non-linearity and temperature errors, allowing for calibration and compensation of the output signal.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If traditional position sensors (RVDTs and resolvers) are used to provide reliable position measurements, then the sensors can operate in critical applications, but the output signals suffer from inherent non-linearity and temperature variations that reduce measurement accuracy
Solution Approach 1:
The patent replaces traditional mechanical position sensing mechanisms with a magnetic field-based system. A magnet is attached to the moving element, and magnetic field sensors (such as Hall effect sensors or magnetoresistive sensors) detect the position by measuring changes in the magnetic field. This substitution eliminates mechanical contact and friction, reducing wear and improving reliability while maintaining measurement precision across temperature variations.
Solution Approach 2:
The patent employs temperature compensation techniques that involve measuring the temperature with a temperature sensor and adjusting the position measurement accordingly. By detecting temperature changes and applying compensation algorithms, the system maintains accurate position readings despite thermal expansion or contraction of components. This parameter change approach directly addresses the temperature variation issue while preserving measurement accuracy.
2Measurement precision
If fully integrated signal conditioning electronics are added to compensate for non-linearity and temperature errors, then measurement accuracy is improved, but device complexity increases
Solution Approach 1:
The patent integrates the magnetic field sensors, temperature sensor, and signal conditioning electronics into a single compact assembly. The signal conditioning circuitry is positioned in close proximity to the magnetic field sensors, allowing for direct connection and reduced signal interference. This merging of components achieves accurate temperature-compensated position measurements while minimizing the overall increase in device complexity through efficient spatial arrangement.
Solution Approach 2:
The integrated circuit performs multiple functions within a single device: it conditions the signal from the magnetic field sensors, reads the temperature from the temperature sensor, applies temperature compensation calculations, and outputs the corrected position measurement. This multi-functionality approach consolidates what would otherwise require separate components, improving measurement accuracy without proportionally increasing device complexity.
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 solution provides a reliable and accurate position measurement by compensating for inherent non-linearity and temperature variations, resulting in a linear output signal that is immune to noise and suitable for high-reliability applications like fly-by-wire systems.
Implementation Method 1
the stator comprising primary windings (24) and secondary windings (25, 26), the secondary windings configured and arranged to provide an output signal (27) as a function of movement of the moving element relative to the stator
Implementation Method 2
The assembly may comprise a temperature sensor (55) configured and arranged to provide a temperature signal (101) to the integrated circuit
Data Source
Figure 1
Figure 2
Figure 3
AI summary
A position sensor assembly comprising (15) a housing (16) having a least one inner cavity, a stator (22) disposed within the housing, a moving element (23) disposed within the housing and configured and arranged to move relative to the stator (22), the stator comprising primary windings (24) and secondary windings (25, 26), the secondary windings configured and arranged to provide an output signal (27) as a function of movement of the moving element (23) relative to the stator (22), electronics (28) disposed in the housing and communicating with the primary windings (24) and the secondary windings (25, 26), the electronics comprising an integrated circuit (29) configured and arranged to provide excitation of the primary windings (24) and to demodulate the output signal (27) of the secondary windings (25, 26), and an input element (35) extending through the housing (16) and connected to the moving element (23).