U.S. NAVY
The Seahorse-class Autonomous Underwater Vehicle from the Applied Research Laboratory at Penn State University is
lowered into the water prior to undergoing launch and recovery testing. At 28 feet, 6 inches, and weighing 10,800 pounds,
Seahorse is an untethered, unmanned, underwater robotic vehicle capable of preprogrammed independent operations.
hopes for such technology. Landay said the service is
experimenting with underwater gliders that can perform antisubmarine warfare functions as well as sample the environment and send data ashore for analysis.
“They’re updating very high-end models and giving
us even more accurate predictions … about the actual
environment that you’re operating in on that day,
rather than trying to take kind of a generic model and
just put a few bits of information in it,” he said.
All of which helps determine where the Navy wants
to put its antisubmarine warfare sensors.
“So it’s really kind of taking things we could always
do in non-real time and trying to make them more real
time so that we can now sample more effectively,”
Landay said. “You’ve got all these different pieces, all of
which have been very valuable … so why don’t we look
at trying to pull all this together?”
Last fall, the vision moved a step closer to reality
when a host of oceanographic researchers, funded
mostly by ONR, gathered in Monterey Bay, Calif., to
test PLUSNet and other similar technologies during a
two-month experiment dubbed MB06.
The PLUSNet portion of the test involved monitoring coastal waters using extremely sensitive underwater microphones, electromagnetic sensors and other
oceanographic instruments, some fixed, others carried
by robot gliders and autonomous underwater vehicles.
The data they gathered was used to help researchers
understand how ocean layers and currents affect the
transmission of sounds and electrical and magnetic
signals generated by marine mammals, ships, sub-
marines and other undersea objects.
“Our aim, mostly for a surveillance type of an application, is so we can predict and then measure sound
propagation of the ocean,” said Dr. Mitchell Shipley,
Penn State University researcher and PLUSNet’s academic program manager. “We’re interested in being able
to hear things clearly and, for the Navy, [they’re] interested in hearing and detecting subs.”
He said the more these undersea robots know about
the environment, the more they can adapt their signal
processing to gain a clearer “picture” of the noise.
“The fundamental premise is that the technology is
mature enough now that we can, with unmanned systems
that are mobile, adapt the sensor field out there to improve
our ability to know what is in an area of the ocean,
whether it be ship traffic, biologics or submarines,”
Shipley said, adding that autonomy and directed mobility
are the two key technologies on which PLUSNet is based.
“If we have an idea from one sensor that we have a signal of interest, then can we use directed mobility to adapt
the field at some other position to keep track of, or investigate or classify, that signal?” Shipley said. “So autonomy
and mobility are kind of the departure that we are pushing, and how much does that autonomy and capability for
directed mobility improve the performance of the surveillance field? That’s kind of an unanswered question.”
Another question that is yet to be answered is the
type of platform the Navy will use to deploy the
PLUSNet system. One idea proffered by the Applied
Physics Laboratory at the University of Washington
would utilize the Navy’s guided-missile submarines.
