Modern robotic crawlers provide a
means of safe and effective remote
data capture, reducing confined space
entries, minimizing data collection times,
enhancing inspection data quality, and
optimizing overall inspection spend.
Introduction
Direct visual testing (VT) is a nondestructive testing
method utilized for surface inspection and eval-
uation. The specifications of direct visual inspec-
tion are defined as placing the eye within 24 in.
(600 mm) of the surface to be examined, at an
angle of not less than 30°, supported by a white
light source with a minimum intensity of 100 fc
(1000 lux). For many industries, direct VT presents
formidable challenges, as the costs to access the
examination area are prohibitively expensive and
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BY RON KESSLER
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inherently dangerous hence, the advent of remote
visual inspection (RVI).
RVI employs the use of remotely operated
camera systems including videoprobes, tube
cameras, robotic crawlers, pan-tilt-zoom (PTZ)
cameras, uncrewed aerial systems (UASs/drones),
and submersible remotely operated vehicles (ROVs).
The remote nature of the data capture, sophistica-
tion of the tooling, and skill of the inspector drives
safe, efficient, and cost-effective inspections in haz-
ardous, inhospitable, and inaccessible plant systems
and components. Moreover, many of these inspec-
tion instruments may be deployed with a wide array
of payloads delivering manipulators, cleaning appa-
ratuses, and varying sensor technologies to encom-
pass a broader range of mission parameters.
Modern robotic crawlers are exceptionally
well-suited for a wide variety of inspection tasks.
As indicated in Figure 1, the assets, applications,
industries, and methodologies can be extensive and
far-reaching. These tools are becoming increasingly
capable of capturing a myriad of inspection data
FOR VISUAL TESTING
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