SYSTEM DESCRIPTION
3
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8020776/12AX / 2019-05-31|SICK
Subject to change without notice
O P E R A T I N G I N S T R U C T I O N S |Free Flow Profiler
3.1
The measurement site
When fully configured with all available options, the FPS features the following system
functions:
•
The
initial
vehicle detection
system function provides a 3D point cloud for the vehicle,
which serves as the basis for calculating the measurements. This system function
typically comprises two
LMS Width
system components and one
LMS Length
system
function. The system components each use an LMS511 SE (system extension) 2D
LiDAR sensor, hereinafter referred to as LMS511.
•
The system function for measuring the vehicle dimensions does not require its own
sensors. It uses the vehicle detection data.
•
The system function for classifying vehicles does not require its own sensors either. It
uses the vehicle detection data.
•
The system function for automatically counting the number of vehicle axles consists of
the
LMS Axle
system component. This system component uses one LMS511 2D LiDAR
sensor.
All the sensor components of the system communicate with the Traffic Controller FPS via
TCP/IP.
3.1.1
Typical layout of the measurement site
The
Layout
of the measurement site depends on the local conditions and on the system
functions to be used. Typically, the system components for vehicle detection are mounted
either above the road on a gantry or to the side of the road on a cantilever arm or post.
This position enables the profile of the vehicle to be captured perfectly and the length to
be calculated. Depending on the system configuration, one or more 2D LiDAR sensors are
responsible for monitoring up to four lanes of a road. One direction of travel is assigned to
each lane.
Within all layouts, the system components are precisely positioned in a 3-dimensional
coordinate system.
Fig. 2: Coordinate system
The following axes are used in this coordinate system:
•
The horizontal axis (X-axis) points orthogonally across the lane. The zero-point of this
axis is the right-hand edge of the lane (when viewed in the direction of travel).
•
The vertical axis (Y-axis) points upward perpendicular to the road surface.
•
The movement axis (Z-axis) points in the direction of travel. The zero-point is located on
the profile measuring plane comprising one or more LMS Width laser scanners.
Note
