Inductive Position Sensor Coil Array Geometry
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Inductive position sensors face inaccuracies due to weak signal strength and low signal-to-noise ratio, leading to larger form factors and dead zones, particularly at signal trace intersections.
Innovation Solution
The implementation of phase blended, arrayed, multiloop inductive coils with layout compensated geometry enhances signal strength, reduces the number of printed circuit board layers, and maintains optimal sinusoidal response, improving sensor performance across various form factors and applications.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If multiple receive coils are combined to produce a stronger signal, then signal strength is improved, but form factor increases
Solution Approach 1:
The receive coil is divided into multiple discrete loops arranged in an array, where each loop contributes to the overall signal. This segmentation allows the coil to achieve stronger signal strength through multiple contributing elements while maintaining a compact form factor by distributing the loops in a spatial array rather than using a single large coil.
Solution Approach 2:
The patent transitions from a single-plane coil design to a multi-layer PCB structure with loops distributed across multiple layers. This dimensional change allows loops to be stacked vertically, increasing signal strength through multiple loops without proportionally increasing the horizontal form factor.
2Reliability
If signal traces intersect to form multiple loops, then signal strength is improved, but dead zones occur at intersections
Solution Approach 1:
The patent applies different geometric characteristics to different parts of the coil structure. Specifically, the loops are designed with non-uniform spacing and varying orientations in different regions, which compensates for the dead zone effects at intersections and maintains signal accuracy across the entire sensing area.
Solution Approach 2:
The coil loops are designed with asymmetric geometries and non-uniform distributions rather than symmetric regular patterns. This asymmetry helps to eliminate dead zones by ensuring that no single intersection point creates a consistent null region, thereby maintaining measurement precision across all positions.
3Ease of manufacture
If standard coil geometry is used, then manufacturing is simplified, but signal-to-noise ratio is low
Solution Approach 1:
The patent modifies key geometric parameters of the coil loops including spacing, orientation, and size distribution across the array. These parameter changes optimize the signal-to-noise ratio by enhancing the magnetic field coupling with the target while maintaining compatibility with standard PCB manufacturing processes.
Solution Approach 2:
The coil array is designed with varying loop characteristics that can be optimized for different operating conditions. The dynamic adjustment of loop parameters across the array allows the system to maintain high signal-to-noise ratio across different target positions and sensing conditions while using standard manufacturing techniques.
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 increases signal strength, improves signal-to-noise ratio, and enhances sensor sensitivity to target position under diverse conditions, ensuring accurate position tracking and robust performance.
Implementation Method 1
EMF is induced by changing the magnetic flux through a wire loop
Implementation Method 2
Eddy currents are induced by either placing a conductor in a changing magnetic field or by relative motion between a conductor and a magnetic field
Data Source
AI summary
Methods and apparatuses to obtain increased performance and differentiation for an inductive position sensor through improvements to the sense element and target design are disclosed. In a particular embodiment, a sense element includes a transmit coil, a first receive coil that includes a first plurality of arrayed loops, wherein two or more of the first plurality of arrayed loops are at least one of phase blended and amplitude arrayed, and a second receive coil that includes a second plurality of arrayed loops, wherein two or more of the second plurality of arrayed loops are at least one of phase blended and amplitude arrayed, and wherein the first receive coil and the second receive coil are phase shifted. The sense element coils are arrayed in several geometries and layouts, and the coil and target geometry are manipulated to compensate for inherent errors in the fundamental design of an inductive position sensor.