Strain Gage Temperature Differential Compensation
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Conventional strain gage sensors face measurement errors due to temperature-induced strain caused by differential expansion and contraction between the strain gage and the base material, especially during dynamic temperature changes, which existing temperature compensation methods fail to adequately address.
Innovation Solution
A network of temperature sensors is placed at each strain gage location to measure temperature differences, allowing for dynamic correction of thermally induced errors through either an analog method by directly compensating induced voltage or a digital method using a mathematical algorithm.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Measurement precision
If conventional temperature compensation methods (thermocouple, thermistor, or diode) are used to correct temperature-induced errors, then static temperature errors are partially corrected, but dynamic temperature gradient errors between different strain gage locations cannot be corrected
Solution Approach 1:
The patent divides the temperature measurement function into multiple independent temperature sensors placed at each strain gage location. Instead of using a single temperature sensor to measure overall temperature, the system segments temperature measurement to capture local temperature variations at each strain gage, enabling correction of temperature gradient effects while maintaining relatively simple individual sensor components.
Solution Approach 2:
The patent implements local temperature measurement by placing temperature sensors directly at each strain gage location rather than using a single remote temperature sensor. This local quality approach ensures that temperature-specific corrections can be applied to each strain gage based on its actual local temperature conditions, accurately addressing temperature gradient effects.
2Measurement precision
If multiple temperature sensors are placed at each strain gage location to measure temperature differences, then temperature gradient errors are corrected, but device complexity increases
Solution Approach 1:
The patent makes the temperature sensor network serve multiple functions: it measures temperature at each strain gage location for gradient correction, and the collected temperature data can also be used for overall thermal characterization of the sensor. This multi-functionality justifies the added complexity by extracting maximum value from the temperature sensor network.
Solution Approach 2:
The patent implements a feedback mechanism where temperature sensors continuously monitor local temperatures at each strain gage location, and this temperature information is fed back to correct the strain measurements in real-time. The feedback loop ensures that temperature-induced errors are dynamically compensated, maintaining measurement accuracy under varying thermal conditions.
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 approach significantly improves the accuracy of strain gauge measurements by effectively mitigating temperature-induced errors, even under conditions of varying temperature gradients.
Implementation Method 1
A network of temperature sensors is placed at each strain gage location to measure temperature differences
Implementation Method 2
Conventional strain gages are typically applied to both stationary and rotating components for this purpose but are susceptible to error induced by temperature
Implementation Method 3
Materials contract and expand with changes in temperature. Difference in expansion coefficients between the gage and the base material can induce strain between the strain gage and the sensor element
Data Source
AI summary
An active temperature differential compensation for strain gage based sensors. An array of temperature sensors can be placed at the gage locations to measure the difference in temperature that induces strain on the strain gages. The output of the temperature sensor network can be placed in series with the strain gage network to directly compensate the induced voltage caused by the temperature gradient and/or employed as the input of a mathematical algorithm that can compensate the output from the strain gage bridge to dynamically correct unwanted thermally induced strain in the strain gages.