Laser Rangefinder Sensor

摘要

The specification discloses a pulsed time-of-flight laser range finding system used to obtain vehicle classification information. The sensor determines a distance range to portions of a vehicle traveling within a sensing zone of the sensor. A scanning mechanism made of a four facet cube, having reflective surfaces, is used to collimate and direct the laser toward traveling vehicles. A processing system processes the respective distance range data and angle range data for determining the three-dimensional shape of the vehicle.

主权项

1. A system for determining the three-dimensional shape of a vehicle, the system comprising:
a distance sensor comprising a laser transmitter and a photodetector, for generating a plurality of laser beams and for detecting a plurality of reflected beams, each of said reflected beams corresponding to one of the plurality of generated laser beams; a scanning mechanism, positioned relative to the distance sensor, for collimating each of said generated laser beams across the vehicle, wherein said scanning mechanism comprises a four facet cube, each having a reflective surface, wherein said four facet cube is positioned relative to the distance sensor such that it is adapted to reflect the generated laser beams, and wherein said scanning mechanism further comprises a scanner control circuit in data communication with said distance sensor to trigger the generation of the laser beams to create predefined scan angles; and a processing system to determine distance ranges from the sensor to portions of the vehicle using time-of-flight measurements derived from timings of said generated laser beams and reflected beams, when the vehicle travels within a sensing zone of the sensor and to determine a three-dimensional shape of the vehicle based on distance ranges.