Abstract: A vehicle detection and classification sensor provides accurate 3D profiling and classification of highway vehicles for speeds up to 100 mph. A scanning time-of-flight laser rangefinder is used to measure the distance to the highway from a fixed point above the road surface and then measure the distance to the surfaces of any vehicle that is viewed by the sensor. The beam is pulsed at a high repetition rate for determining vehicle speeds with a high accuracy and uses the calculated speed and consecutive range measurements as the vehicle moves past the sensor to develop a three-dimensional profile of the vehicle. An algorithm is applied to the three-dimensional profile for providing a vehicle-classification. A laser is also used to count the number of axles associated with the vehicle.

Abstract: A vehicle detection and classification sensor provides accurate 3D profiling and classification of highway vehicles for speeds up to 100 mph. A scanning time-of-flight laser rangefinder is used to measure the distance to the highway from a fixed point above the road surface and then measure the distance to the surfaces of any vehicle that is viewed by the sensor. A rotating polygon scans a beam laser into two beams projected across the road surface at a fixed angle between them. The beam is pulsed at a high repetition rate for determining vehicle speeds with a high accuracy and uses the calculated speed and consecutive range measurements as the vehicle moves past the sensor to develop a three-dimensional profile of the vehicle. An algorithm is applied to the three-dimensional profile for providing a vehicle-classification.

Abstract: A sensor using laser range imaging technology is adapted for determining a three-dimensional profile of a vehicle passing the sensor for use in Intelligent Vehicle Highway Systems. A continuously pulsed laser beam scanned across a detection area determines the presence of a vehicle. Range, angle and time date for a vehicle passing the sensor are collected and stored for use in determining its three-dimensional profile. Forward and backward beams are directed for scanning across the detection area. Pulsed energy is sent into the two divergent beams, which are received as reflective energy in a receiver. The receiver accepts reflections from the beams and provides inputs for purposes of determining time of flight, and for measuring the time interval between interceptions of the two divergent beams for a given vehicle. An encoder tracks the position of the mirror for providing angle data with associated range measurements.

Abstract: An Intelligent Vehicle Highway System (IVHS) sensor provides accurate information on real-time traffic conditions that can be used for incident detection, motorist advisories, and traffic management via signals, ramp meters, and the like. A diode-laser-based Vehicle Detector And Classifier (VDAC) measures the presence, speed, and three-dimensional profiles of vehicles passing beneath it within its multi-lane field-of-view coverage. The sensor uses pulsed laser range imaging technology adapted for determining the three-dimensional profile of the vehicle. The VDAC employs a rotating polygon mirror to scan a pulsed laser rangefinder across three lanes of a highway in order to measure the presence, speed, and height profiles of vehicles in all three lanes simultaneously. A receiver accepts reflections from beams transmitted from the sensor and provides inputs for determining time of flight, and a time interval between interceptions of the two divergent beams for the vehicle.

Abstract: A sensor using pulsed laser range imaging technology is adapted for determining a three-dimensional profile of a vehicle passing the sensor for use in Intelligent Vehicle Highway Systems. A continuously pulsed laser beam scanned across a detection area determines the presence of a vehicle. Range, angle and time date for a vehicle passing the sensor are collected and stored for use in determining its three-dimensional profile. Forward and backward beams are directed for scanning across the detection area. Pulsed energy is sent into the two divergent beams, which are received as reflective energy in a receiver. The receiver accepts reflections from the beams and provides inputs for purposes of determining time of flight, and for measuring the time interval between interceptions of the two divergent beams for a given vehicle. An encoder tracks the position of the mirror for providing angle data with associated range measurements.

Abstract: An object sensor and method using pulsed laser range imaging technology is adapted for determining the velocity and three dimensional profile of a vehicle passing the sensor for classifying the type of vehicle for use in Intelligent Vehicle Highway Systems. A pair of scanned laser beams are provided by splitting a continuously pulsed laser beam from a transmitter and an optical receiver determines the presence of a vehicle in a predetermined zone such as a highway weigh station or toll booth. Range, angle and time data are collected and stored for use in determining the speed of the vehicle passing the sensor and its three dimensional profile. Forward and backward scanned beams are provided using alternate embodiments of a rotating mirror and using two transmitters/receivers in another embodiment. The pulsed energy is sent into the two divergent beams, which are received as reflective energy in a receiver.

Abstract: The sensor includes a range finder having means for emitting a directional output of pulsed energy toward a fixed area, and includes a transmitter section which divides pulsed energy into divergent beams, which are then received as reflective energy in a receiver section. The receiver alternately selects between outputs of two detectors receiving reflections from the beam and provide inputs for purposes of determining time of flight, and for measuring the time interval between interceptions of the two divergent beams for a given object. The sensor also receives inputs indicating the time that each pulse is emitted and the selected outputs from the detector to indicate when returning energy is received from the corresponding pulse to determine the elapsed time between the two.