Measurement of the Rail Track Profile with Digital Images

      This project was accomplished for my master's degree in Advanced Surveying Enginering. It was funded by the National Rail Ministration in China.
      The major public transportation in China is the train. The inspection and maintenance to the rail track have gained increasing attention. At that time (1993), people measured the rail track by the equipment shown in the figure below. The system developed by us successfully achieved the automation of the track inspection.
      We applied light section to the measurement of the track profile. In concept, a plane sheet of light illuminates the object under inspection so as to cast a bright light on its surface. The shape of this line is then the outline to the object.
     This project involved camera calibration and image processing. These source codes were implemented by Microsoft C.

Traditional method	Developed automatic method

Image obtained by left camera	Image obtained by right camera

The measurement result by the traditional method	The measurement result by our developed method

In the above two figures, the top curve is the surface curve of a new track,
the curve below is the surface curve of a worn track.

Home