Cursor Band Layout for Unambiguous Inductive Linear Position Sensing
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Inductive rotation angle sensors face ambiguity issues in interpreting multiple turns of steering wheel movement, are large and expensive for long path measurements, and are unsuitable for steer-by-wire systems requiring precise position control.
Innovation Solution
An elongate body with a cursor band for an inductive linear displacement sensor, featuring conductive pads and non-conductive sections, allows precise measurement of long paths in a compact and cost-effective design, using the nonius principle to eliminate ambiguity.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Measurement precision
If inductive rotation angle sensors are used for position measurement, then measurement precision is improved, but ambiguity arises in interpreting multiple turns
Solution Approach 1:
The cursor is divided into multiple cursor pads (at least two) arranged along the movement direction, with at least one pad being longer than the others. This segmentation allows the sensor to distinguish between different positions and turns by detecting which pads are active, eliminating ambiguity while maintaining precision.
Solution Approach 2:
The invention transitions from a single-point cursor to a multi-point cursor distribution along the movement direction. This dimensional expansion allows the system to encode turn information through the spatial arrangement of active cursor pads, resolving the ambiguity problem.
2Length of moving object
If inductive rotation angle sensors are designed for long path measurements, then measurement range is improved, but device size and cost increase
Solution Approach 1:
By segmenting the cursor into multiple pads of different lengths, the sensor can measure long paths (30-40 cm) using a compact stator structure. The varying pad lengths create distinct inductive coupling patterns that encode long-displacement information without requiring a proportionally large sensor volume.
3Measurement precision
If inductive rotation angle sensors are used for steer-by-wire systems, then position control capability is improved, but ambiguity and complexity increase
Solution Approach 1:
The segmented cursor with multiple pads of varying lengths provides unambiguous position information for steer-by-wire systems. The evaluation circuit processes the inductive coupling signals from different pads to determine precise position, eliminating the complexity of handling ambiguous multi-turn data.
4Ease of manufacture
If traditional cursor designs are used, then manufacturing simplicity is maintained, but measurement ambiguity occurs
Solution Approach 1:
The cursor is segmented into multiple pads that can be manufactured as separate elements or integrated into the cursor body. This segmentation enables unambiguous measurement while maintaining relatively simple manufacturing processes, as each pad can be independently optimized for its inductive coupling characteristics.
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 robust and precise measurement of linear position without ambiguity, suitable for steer-by-wire systems, with a compact and inexpensive design that can measure up to 30-40 cm paths accurately.
Implementation Method 1
The at least one cursor band is designed with a plurality of electrically conductive cursor pads in order to inductively couple at least one excitation coil to at least one sensor coil of a stator of the linear displacement sensor
Data Source
AI summary
An elongate body for a vehicle system of a vehicle, the body having at least one cursor band for an inductive linear displacement sensor, the at least one cursor band extending in the direction of a longitudinal extent of the body, the at least one cursor band being designed with a plurality of electrically conductive cursor pads in order to inductively couple at least one excitation coil to at least one sensor coil of a stator of the linear displacement sensor and being designed with non-coupling sections which are electrically less conductive or non-conductive with respect to the cursor pads, the cursor pads being spaced apart from one another in the direction of the longitudinal extent in each case by the non-coupling sections, and the cursor pads of the cursor band being formed on the body.