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Vision Sensor SBSI/SBSC-EN, 8062650 - 1607b - 13/09/2016
Vision Sensor Manual
- red: calibration not valid
With new job:
- red: as so far no calibration with calibration plate happened
Fig. 52: Selection of calibration method
Detailed description
Method
Functions
None
Calibration not active, coordinate calculation, display and output in pixel
(px)
Scaling (Measurement)
(Relative calculation of
distances in world
coordinates)
The calibration method "Scaling" serves relative calculation of distances
in world coordinates (mm).
This is realized with a simple factor.
There is only one factor for both coordinate axis X and Y.
The advantage is the very simple function, but accuracy is limited.
Errors caused by tilt angle against perpendicular view to the
measurement plane or by lens distortion are not corrected by this
method.
World coordinates are not absolute. The coordinate values refer to
the principal point in left, upper corner or the field of view.
Example:
Determination of distances between two objects in mm.
(Limited accuracy)
Point pair list
(Robotics / Pick and
Place)
(Absolute calculation in world
coordinates, in a user defined
reference system, e.g. robot
coordinate system)
The calibration method "Point pair list" serves absolute calculation of
positions in world coordinates (e.g. mm).
Errors caused by scaling, x- and y- axis separately, tilt angle against
perpendicular view to the measurement plane or by lens distortion are
all corrected by this method.
Example:
Determination of absolute positions of objects in world
coordinates in millimeter (e.g. robot coordinate system)
This is realized by the image capturing of a calibration part which is
placed by the robot in the field of view.
A point pair is set by:
- Image coordinate by graphical input in the image, or by numerical input
of a value
- World coordinate by numerical input given from the robot controller
Summary of Contents for SBSC-EN
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