Analog Torque Sensor Inductive Coupling High-G

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Existing torque measurement systems face challenges in high-G force environments due to centrifugal forces, which limit the life and tolerance of electronic components, and require precise timing that is difficult to maintain without crystals, especially in applications like Voltage to Frequency Converter systems.

Innovation Solution

A remotely powered and remotely interrogated wideband torque measurement device operating entirely in the analog domain, using strain sensors and Voltage to Frequency Converters with inductive coupling for power and signal transmission, eliminating the need for digital components and crystals.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Measurement precision

If electronic components are mounted on rotating shafts to enable torque measurement, then measurement capability is achieved, but centrifugal forces increase exponentially with radius, limiting component life and tolerance

Engineering Contradiction:
Improvetorque measurement capabilityVSAvoidcomponent life and tolerance
Core Design Contradiction:
Measurement precisionVSReliability

Solution Approach 1:

The system divides the measurement function into two separate segments: strain sensing elements mounted on the rotating shaft, and electronic processing components mounted on the stationary support structure. This segmentation allows the shaft to rotate freely without carrying heavy electronics, reducing centrifugal forces while maintaining measurement capability through inductive coupling for signal transmission.

Inventive Principle:
Principle #1Segmentation

Solution Approach 2:

An inductive coupling system acts as an intermediary between the rotating shaft and stationary support structure. This intermediary enables both power transmission and signal communication without direct mechanical or electrical connections, allowing strain measurements from rotating strain gages to be transmitted to stationary electronics while eliminating the need to mount electronics on the rotating shaft.

Inventive Principle:
Principle #24Intermediary (Mediator)

2Measurement precision

If crystal-controlled oscillators are used on rotating shafts for precise timing, then timing accuracy is improved, but the complexity and reliability issues of digital components under high-G forces increase

Engineering Contradiction:
Improvetiming accuracyVSAvoiddigital component complexity
Core Design Contradiction:
Measurement precisionVSDevice complexity

Solution Approach 1:

The system replaces complex digital timing circuits with a simpler analog frequency-to-voltage conversion approach. Instead of using crystal-controlled oscillators and digital processing on the rotating shaft, the invention uses an operational amplifier-based frequency-to-voltage converter that generates a DC voltage signal proportional to shaft speed, eliminating the need for complex digital timing components in the rotating assembly.

Inventive Principle:
Principle #28Mechanics substitution (Replace mechanical system)

3Device complexity

If RC oscillators are used instead of crystal-controlled oscillators to reduce complexity, then device complexity is reduced, but timing precision deteriorates due to temperature drift

Engineering Contradiction:
Improveoscillator circuit complexityVSAvoidtiming precision
Core Design Contradiction:
Device complexityVSMeasurement precision

Solution Approach 1:

The inductive coupling system serves as an intermediary that enables the use of simple RC oscillators on the rotating shaft while maintaining timing precision. The RC oscillator generates a frequency signal that is transmitted through the inductive coupling to the stationary side, where the frequency-to-voltage conversion occurs. This intermediary arrangement isolates the simple oscillator from temperature-sensitive components, allowing RC oscillators to be used without sacrificing measurement precision.

Inventive Principle:
Principle #24Intermediary (Mediator)

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 provides precise and reliable torque measurement in high-G force applications up to 10,000 Gs, maintaining timing accuracy without crystals, and reducing development costs and complexity, while ensuring robustness and reliability.

Implementation Method 1

The coil is inductively coupled to a remotely located non-rotating electrical component and configured to power the strain sensor via power received from the non-rotating electrical component and transmit the frequency signal to the non-rotating electrical component

Methodology Applied
Scientific EffectInductive coupling: Electromagnetic Induction

Data Source

PatentEP3172546B1Remotely powered and remotely interrogated torque measurement devices
Publication Date: 2020.06.03 LORD CORP
  • EP3172546B1 patent drawingFigure 1
  • EP3172546B1 patent drawingFigure 2A
  • EP3172546B1 patent drawingFigure 2B

AI summary

Torque measurement devices, systems, and methods are provided. Exemplary torque measurement devices, systems, and methods include providing rotating electronics and non-rotating electronics configured for remote power transmission and remote interrogation via near field and switched reactance communications. The rotating electronics and the non-rotating electronics can communicate analog information without batteries or a physical connection therebetween.