concerned? Does it represent the way of the future, or is it
just a new variation on a well-established theme?
Industry experts say it depends on how you define the
terms. Recent technology breakthroughs have improved
the capabilities of both AGVs and AMRs, blurring the lines
between them and creating a marketplace full of diverse
tools that can be matched to almost any logistics task.
SMART VEHICLES GET SMARTER
To understand the difference between traditional AGVs and
the newer AMRs, it helps to know a little about the vehicles’
background. The AGV has traditionally been defined as a
kind of robotic cart that lifts and ferries loads
around a facility without human assistance.
Although it doesn’t rely on a driver for navigation, it does require external guidance—electric
wire buried in the concrete floor, lines of magnets, tape, beacons, or reflectors. The main rap
on these vehicles is that changing that path—say,
to accommodate a new product, a new client, a
new facility, or a reconfigured workflow—can be
time-consuming and expensive.
The AMR, by contrast, is a self-guided vehicle
outfitted with software and intelligent sensors
that enable it to navigate its own path around
the DC. It’s that capability for onboard navigation that sets the new breed of self-driving warehouse vehicles apart from their predecessors,
said John Santagate, research director for commercial service robotics at IDC Manufacturing Insights, an
analyst group based in Framingham, Mass.
By using suites of onboard sensors and processors, AMRs
can perform complex tasks like simultaneous location and
mapping (SLAM) to “learn” their way around a new site.
They rely on artificial intelligence (AI) to sense and respond
to a changing environment, and to optimize their routes.
Some AMRs can also leverage “swarm intelligence,”
meaning they’re able to exchange data with other units
through wireless networks and adjust their operations
based on what they learn. That means they can, say, adjust
their paths based on information received from other units,
much the way drivers do on a crowded highway, or even
“teach” new arrivals how to navigate a particular warehouse. That’s a key advantage of those models and some
next-gen AGVs—one that conventional AGVs can’t match.
A PEACEFUL COEXISTENCE?
There’s no doubt that AMRs are the hot technology of the
moment, as indicated by high-profile deals like transportation and logistics giant XPO Logistics Inc.’s recent purchase
of 5,000 mobile robots from GreyOrange Pte. Ltd. for use in
e-commerce fulfillment.
That notwithstanding, AMRs are still a young, emerging technology, according to IDC’s 2018 Autonomous
Mobile Robots in the Warehouse and Fulfillment Center
MaturityScape Benchmark Survey, which looks at the current state of AMR deployments in fulfillment operations.
The study showed that 47. 2 percent of users were still at
the “ad hoc” or “opportunistic” level of AMR adoption,
running only sporadic or pilot programs, while 33. 8 percent
were at the “repeatable” stage, where they are just beginning
to expand their deployments. That leaves 15. 2 percent at
the advanced “managed” stage of maturity, where they
are achieving competitive advantage through AMRs, and
just 3. 8 percent at the fully “optimized” stage of
widespread adoption, IDC found.
By contrast, AGVs are entrenched in many
U.S. logistics facilities, with operations that have
been running for decades and are on track to
continue for years to come, Santagate said. In
those cases, companies introducing AMRs into
their operations will most likely use them in
combination with AGVs and other automated
equipment, with the units all working together
in a symphony of machines.
Like Santagate, systems integrator Dematic,
a division of German material handling giant
Kion Group AG, doesn’t see AGVs going away
anytime soon. In a white paper titled Automated
Guided Vehicles (AGVs) vs. Autonomous Mobile
Robots (AMRs): Debunking the Myths, Dematic
argues that AGVs will continue to fill an important role
in the warehouse for some time to come, relieving human
workers of nonvalue-added repetitive material movement
tasks. Although some AMR proponents might give the
impression that AGVs are antiquated and obsolete, that’s
misleading, the company says. Leaps in AGV technology in
the last 10 years have added new weapons to their arsenal,
including vision-based guidance, dynamic routing, and
three-dimensional (3-D) sensors.
BLURRED LINES
In the meantime, the categories of mobile warehouse vehicles continue to evolve, muddying the waters for those
who contend AMRs are defined by the navigation sensors
they carry, said Jeff Christensen, vice president of products
at Seegrid Corp., an AGV firm that makes vision-guided
vehicles.
Seegrid sees a future where autonomous onboard navigation will become a requirement for new warehouse vehicles.
“Dependent navigation is very predictable; when people
buy that, they’re not buying a cool machine; they’re buying
predictability,” Christensen said. “But in DCs where every
pallet is going a different route to a different location, fixed
