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detecting possible erroneous measurements of the laser sensor.
The image processing technique chosen for the MOSTAR interface
is edge detection. Analysis of the edges inside the images of the robot
workspace have been used to detect walls and potential obstacles. A
technique has been implemented for finding the nearest objects that
the robot is facing, by individuating the borders of the bases of these
objects (section 8.2).
Once the edges of nearest objects are detected, it is necessary to
integrate them with laser data somehow. Two techniques of integration
have been developed and implemented:
• a technique employing edges to improve camera alignment (sec-
tion 8.3);
• a technique employing edges to correct wrong laser measurements
and individuate obstacles which are invisible to laser (section 8.4);
5.2.4 Extension of the AR interface to stereoscopic visualization
As exposed in section 4, stereoscopic visualization helps to reduce colli-
sions during robot teleguide, by enhancing the user’s depth estimation.
Since stereo can positively influence visualization of both real and syn-
thetic images (as it was proven in [59, 60]), the MOSTAR interface can
definitely benefit from it.
Stereoscopic visualization has been easy to implement in the MOS-
TAR interface. MORDUC cameras already provide a synchronized
stereo couple of images, which can be directly displayed to the user.
On the other hand, 3D virtual objects can be easily rendered from two
different viewpoints, and each view of the objects can be overlaid on
the corresponding real image.
The main issue in the stereo extension of the MOSTAR visualiza-
tion interface has been guaranteeing a suitable disparity level between
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