Development of traffic counters by laser range scanners

The author has been developing traffic counters by using multiple laser range scanners. The targets to count are pedestrians and automobiles. Laser range scanners are useful for detecting objects under the static background. The standard way of using laser range scanners is to use it to scan a horizontal view of a certain height. However, by scanning vertically, it is possible to get information of the height of the target as well as the position information. Although we cannot trace the target by scanning this way, the author has successfully made a system to estimate the direction of the targets. The developed system can be used for counting pedestrians or cars exclusively, and it cannot be used for the situations where cars exist among many pedestrians, but it does not impose a large constraint, since the situation of counting pedestrians and automobiles are usually different. As an automobile counter, we use only one sensor. The direction of the automobiles are figured out from the position of the target running. The error for pedestrian count is less than 5%, which seems sufficient for actual implementation in many cases of investigate of traffic amounts.