Advanced dynamic obstacle-detecting system for railway surroundings using a highly accurate laser-sectioning method

A dynamic obstacle detecting system developed for railway surroundings has been further developed and improved. The experimental system was developed in 1990 and an original laser sectioning method was examined on the Takayama Line. It was confirmed that the measurement accuracy of the obstacle´s locations was about 10 mm at speeds of 7 km/h in view fields around the construction gauge, but that it deteriorated at higher speeds because of fluctuations of the system. The current system has been newly refined for practical use. A range error caused by fluctuations was corrected by the detection of the rail locations, and effects from unwanted exposure to a fluorescent lamp were eliminated. Measurements of a test model were carried out on a sidetrack at speeds up to 40 km/h. It was confirmed that the relative range error of 6.9 mm was reduced to 3.6 mm by the correction method developed