Aerospace & Defense Technology - October 2021 - 6

Unmanned Vehicles & Robotics
The World Shipping Council estimates that an average of roughly 1400 containers are lost at sea every year.
tion and componentization of their separate
sonar, robotics, and software functions.
AUV manufacturers such as Teledyne
Gavia design their systems to
support that modularity. Technology
components such as AutoTRap Onboard
can be integrated from different,
specialized vendors at lower costs than
building a single monolithic solution.
Defense and Commercial
Applications
In the defense community, seafloor
object detection tools are sought after
primarily for mine countermeasures operations.
Undersea mines have long
played a critical role in marine warfare
and can pose a major threat to naval
personnel around the world. In the
mine hunting context, object detection
is commonly referred to as automatic
target recognition (ATR).
Large-scale ATR systems have been
available much longer than AUV-based
ATR solutions, according to Balasuriya.
They tend to use ship- or submarinetowed
sonar and rely on a monolithic design
and integration of sonar, software,
and ship. This historical class of largescale
ATR solutions has typically required
nation-state level funding to develop and
acquire. The more recent generation of
modular and affordable AUV-based components
can be seen as a complement to
existing large-scale ATR systems.
Outside of defense, different users
need computer vision tools to detect and
analyze a broad range of objects: pieces
of airplane wreckage (for search and rescue),
lost shipping containers (for shipping
insurance claim verification), and a
variety of offshore oil, gas, and wind infrastructure
components, which require
regular evaluation and maintenance. For
these communities, AUVs and other marine
robotics now deliver computer vision
capabilities that were formerly only
available for defense applications.
The development of object detection
technology for the undersea domain
has posed unique difficulties. Air is easy
to see through with optical and infrared
cameras, which have become extraordinarily
widespread and affordable. In
contrast, water absorbs optical light
within a few meters. For that reason,
sonar technology has long been the tool
of choice for " seeing " through water
and for imaging the seafloor.
Sonar Technology
Current generation AUVs come
equipped with different types of modular
sonar devices, including side scan
sonar, forward looking sonar, and synthetic
aperture sonar (SAS). Both highfrequency
and low-frequency systems
are available, providing relatively
higher or lower spatial resolution, respectively.
Centimeter resolution is
readily achievable for SAS. Side scan systems
are lower resolution but more
widely developed.
Sonar imagery introduces new complications
to object detection. An engineer
might expect to directly employ
existing convolutional neural networks
(CNN) technology on sonar imagery, especially
as sonar images can look
roughly similar to aerial photography of
Deep learning solutions show excellent performance for optical object detection and classification (left); and for adjacent tasks like de-noising images (center, right).
6
Intro
Cov
www.aerodefensetech.com
ToC
+
-
Aerospace & Defense Technology, October 2021
A
µ
È

http://www.aerodefensetech.com http://info.hotims.com/79418-967

Aerospace & Defense Technology - October 2021

Table of Contents for the Digital Edition of Aerospace & Defense Technology - October 2021