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SYSTEM DESCRIPTION
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8017768/12AX/2019-05-31|SICK
O P E R A T I N G I N S T R U C T I O N S | TIC
Subject to change without notice
3.4.3
Operating principle of the function for calculating the vehicle dimensions
In addition to the vehicle class, the vehicle width, the vehicle height and the vehicle length
as well as the speed of the vehicle are determined from the 3D point cloud.
Since the dimensions are not measured, but only calculated, no accuracy can be
specified. The TIC profiling system therefore only provides an indication of vehicle
dimensions.
For a TIC501, the calculations of the speed and length information are less accurate than
for the TIC102 and TIC502 system functions due to the lack of an LMS Length.
3.4.4
Operating principle of the vehicle axle counting function
The respective 2D LiDAR sensor for counting the number of axles is mounted at the edge
of the lane and captures the side of the passing vehicle. In order to count the number of
axles and determine the axle position and, if applicable, the height of the first axle, the
system also needs to access the measuring points of the 3D point cloud.
Determining the number of axles
•
In order to determine the number of axles, the first step is to analyze point patterns of
the wheels and shadow patterns on the roadway. Combining the two analysis methods
helps to achieve a high level of measurement accuracy.
The areas containing wheels (and, by implication, axles) can be expected to generate
very few measurement points, if any at all.
In contrast, a large number of measurement points will be detected in areas of the
vehicle where there are no wheels (and, in turn, no axles) and the 2D LiDAR sensor is
able to look “underneath” the vehicle to a certain extent.
Fig. 28: Operating principle of axle counting – Wheel detection using shadow patterns
Note
