At the National Traffic Safety and Environment Laboratory, we proposed a train control system using satellite positioning and general-purpose radio. However, in sections such as tunnels where satellite positioning is not possible, it is necessary to combine this with other methods of determining the absolute position. Therefore, we considered a method to accurately determine the absolute position of the vehicle by ascertaining the feature points by using a Light Detection and Ranging (LiDAR) sensor. In addition, as validation of the performance of the single LiDAR sensor, we installed a LiDAR sensor on a train to study its detection of humans and cars. Through validation of its performance in addition to its potential for absolute position detection, we tried to assess its effectiveness as an obstacle detection device for the future. The probability of accidents between an automobile and a tram is higher at an intersection. Hence, a specific aim of the basic experiments was to ascertain the possibility of using the LiDAR sensor to judge the approach of a car turning right onto a tram track at an intersection. The results of these experiments are reported here.
absolute position, LiDAR sensor, obstacle detection, satellite positioning, three-dimensional space recognition sensor
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