Users Manual

Description of run-time parameters
out1
_
mode and out2
_
mode (Out1 and Out2) The output modes for GPIO Out 1 and Out 2 can be set individu-
ally:
Low sets the ouput permanently to low. This is the factory default of Out 2.
High sets the output permanently to high.
ExposureActive sets the output to high for the exposure time of every image. This is the factory default
of Out 1.
ExposureAlternateActive sets the output to high for the exposure time of every second image.
Note: The parameters can only be changed if the IOControl license is available on the rc_visard. Otherwise,
the parameters will stay at their factory defaults, i.e. out1
_
mode = ExposureActive and out2
_
mode = Low.
Figure Fig. 7.2.1 shows which images are used for stereo matching and transmission via GigE Vision in
ExposureActive mode with a user defined frame rate of 8 Hz.
Internal acquisition
Camera image
GPIO Out 1
Disparity image
Fig. 7.2.1: Example of using the ExposureActive mode for GPIO Out 1 with a user defined frame rate setting of
8 Hz. The internal image acquisition is always 25 Hz. GPIO Out 1 is high for the exposure time of every image.
A disparity image is computed for camera images that are send out via GigE Vision according to the user defined
frame rate.
The mode ExposureAlternateActive is meant to be used when an external random dot projector is connected
to the GPIO Out 1 of the rc_visard. A side effect of setting output 1 to ExposureAlternateActive is that
the stereo matching (Section 6.2) component only uses images if output 1 is high, i.e. projector is on. The
maximum framerate that is used for stereo matching is therefore halve of the frame rate configured by the user
(see FPS, Section 6.1.3). All other components like visual odometry (Section 6.4), TagDetect (Section 7.3) and
ItemPick (Section 7.4) use images where the output is low, i.e. projector is off. Figure Fig. 7.2.2 shows an example.
Internal acquisition
Camera image
GPIO Out 1
Disparity image
Fig. 7.2.2: Example of using the ExposureAlternateActive mode for GPIO Out 1 with a user defined frame
rate setting of 8 Hz. The internal image acquisition is always 25 Hz. GPIO Out 1 is high for the exposure time
of every second image. A disparity image is computed for images where Out 1 is high and that are send out via
GigE Vision according to the user defined frame rate. In ExposureAlternateActive mode, images are always
transmitted pairwise. One with Out 1 high for which a disparity image might be available and one with Out 1 low.
Note: In ExposureAlternateActive mode, an image with output high (i.e. with projection) is always 40 ms
away from an image with output low (i.e. without projection), regardless of the user configured frame rate.
This needs to be considered when synchronizing disparity and camera images without projection in this special
mode.
The functionality can also be controlled by the digital IO control parameters of the GenICam interface (Category:
DigitalIOControl, Section 8.1.1).
7.2. IO and Projector Control 73