Bi-Circuit Wheel Load Sensor for Accurate Dynamic Force Measurement
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing wheel load sensors in the railroad industry struggle to provide consistent and accurate measurements of wheel/rail dynamic loads, leading to inconsistent safety evaluation standards between on-board and wayside measurements.
Innovation Solution
A wheel load sensor system featuring two independent shear load sensing circuits with different spacings, one with wide spacing and the other with narrow spacing, fixed along the neutral axis of the rail. These circuits are calibrated to generate sensitivity curves, allowing for precise determination of dynamic load state, including longitudinal position and magnitude of impact loads.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Measurement precision
If a single shear load sensing circuit is used, then the device complexity is reduced, but the measurement precision and ability to determine longitudinal position accurately deteriorates
Solution Approach 1:
The sensing system is segmented into two independent shear load sensing circuits with different spacings (first spacing and second spacing). This segmentation allows each circuit to sense wheel load at different longitudinal positions, enabling the system to determine both the magnitude and longitudinal position of the load through comparative analysis of the circuit responses.
2Reliability
If wayside measurement systems are used, then continuous measurement is enabled, but the measurement precision and consistency with on-board measurements deteriorates
Solution Approach 1:
The patent applies parameter changes by varying the spacing between strain gauges in the two sensing circuits. The first circuit has a first spacing and the second circuit has a second spacing, creating different sensitivity characteristics. This parameter variation allows the system to compensate for measurement discrepancies and achieve consistency between wayside and on-board measurement methods.
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 system achieves consistent results for on-board and wayside wheel/rail vertical force measurements, enabling precise determination of dynamic load states and improving safety evaluation standards by providing accurate longitudinal position and magnitude of dynamic peak loads.
Implementation Method 1
The wheel load sensor system employs at least two sets of strain gauges arranged in two independent shear load sensing circuits
Data Source
AI summary
A wheel load sensor system has two independent shear load sensing circuits, a wide circuit and a narrow circuit, that are fixed along the neutral axis of the rail in the span between ties. The responses of both circuits are initially calibrated by applying known loads at predetermined points along the span to generate sensitivity curves from each circuit. This configuration allows the present system to account for the longitudinal position of the load applied within the crib based on the ratio of the response signals from the two circuits. This ratio can be used to accurately determine the location of the wheel load within the crib. The magnitude of the load can then be calculated from the sensitive curve for either circuit.