Dynamic Measurement for Wheel Diameter of Train Based on High-Speed CCD and Laser Displacement Sensors

摘要

Wheel set is the major running components and most important parts of a train. Wear degree of wheel diameter increases with the speedup of train. Measurement of diameter parameters is an important step for the safety of train vehicle. A dynamic measuring method for diameter parameters of running wheel set based on high-speed CCD and laser displacement sensors was proposed. The method used precision laser displacement sensor, high-speed and high resolution CCD and digital image processing technology to realize the non-contact automatic measuring of wheel set parameters. These parameters include the diameter, roundness and diameter difference. Step of image processing and diameter calculation were analyzed. Main influence factors for measuring accuracy were analyzed. Dynamic measuring system was designed. The system included wheel detector, laser displacement sensor, semiconductor laser source, high-speed CCD, online image trigger and acquisition system. Measuring accuracy of wheel diameter parameters was within 1.2 mm while train was running in a limited speed less than 80 km/h.