SICK Ranger E

Reference Manual Chapter 5
Ranger E/D
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Configuring Ranger E and D
5.7 Range Measurement Settings
The range components (HorThr, HorMax, HorThrMax and Hi3D) measure the range by
determining the location of a laser line in each column of the ROI. The differences between
these components are the method they use for locating the laser line in each column:
HorThr, HorThrMax The middle of the range of rows where the intensity is above a
specified threshold value.
HorMax The row where the intensity is the highest.
Hi3D Uses an algorithm similar to center-of-gravity.
Figure 5.9 – Different methods for locating the laser line in a column. The diagrams show
the intensity for the rows in one column, which corresponds to a cross-
section of the laser line.
If a column contains multiple intensity peaks (where the intensity values are above the
thresholds), the HorThr and HorThrMax components will use the first encountered peak for
determining the range. For these components you can specify in which direction the
sensor image should be searched – from top to bottom, or from bottom to top – with the
Acquisition direction parameter. This can be useful for example for avoiding reflexes to be
interpreted as the laser line.
Figure 5.10 –If a column contains multiple intensity peaks, the first encountered peak is
considered to be the laser line.
Note that changing the acquisition direction will also reverse the range axis – that is the
range will be measured from the bottom of the ROI. You can manually reverse the axis by
changing the value of the Range axis parameter.
The range component can also use pulsed illumination, in which case a signal for trigger-
ing the pulse is sent on Out2. The length of the trig pulse is set by the Laser pulse time
parameter. If a configuration uses multiple range components, only one of them can pulse
the illumination.
Threshold Ma
x
Center-o
f
-
g
ravity
A
cquisition direction
Threshold
A
cquisition direction
Intensity
Ro
w
Intensity
Intensity
Ro
w
Ro
w
Intensity Intensity
Ro
w
Ro
w