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Real-time vertical track deflection measurement system

Sheng Lu, University of Nebraska - Lincoln


Track quality is a major factor in railroad safety, and one accepted indicator of track quality is the vertical track deflection. Measuring track deflection from a moving railcar is difficult because there is no stable reference for the measurements. ^ A system developed by researchers at the University of Nebraska to measure track deflection from a moving railcar in real-time is described in detail. The system consists of a loaded hopper with a camera/laser sensor system to detect the vertical deflection of the rail relative to the wheel/rail contact point. Modeling and simulation of the system is also presented along with the mathematical models which can be used to estimate track modulus. ^ The measurement system has been used to conduct revenue service tests over three thousand miles of track. A special validation test was also performed. The results from these tests have shown that the system's measurement is repeatable and accurate; the system has notable ability to indicate track support problems. ^

Subject Area

Engineering, Mechanical

Recommended Citation

Lu, Sheng, "Real-time vertical track deflection measurement system" (2008). ETD collection for University of Nebraska - Lincoln. AAI3331436.