operator but move from place to
place on their own. Others pick and
put away pallets entirely on their
own, with no operator involved. All
boost productivity by reducing the
amount of time warehouse workers
spend searching for pick and putaway
locations, walking and driving, and
stepping on and off vehicles.
Automated industrial trucks have
been available in Europe, Asia, and
Australia/New Zealand for several
years now. But driverless vehicles are
still new to North America. Although
vendors say the trucks offer double-digit productivity improvements,
warehouse operators aren’t rushing
to buy yet. Before they invest in new
technology, potential buyers want to
know whether the productivity benefits make automated trucks a “must
have” or if this is just another example of a “gee whiz” technology in
search of an application.
PHOTO COURTESY OF CROWN EQUIPMENT CORP.
WHAT THEY DO AND HOW
THEY DO IT
To get a handle on the potential benefits of automated forklifts and pallet
trucks, it helps to compare them with
AGVs. The line between them is an
increasingly blurry one, especially as
AGV manufacturers increase flexibility and slash their machines’ prices.
But in general, AGVs are designed to repetitively transport items along a fixed path. The vehicles usually are
guided by tape, laser reflectors, wires, or magnets located
on a facility’s floor, and they typically have no operator
compartment. They can be switched to manual mode,
but this can take a little time and the AGV must be moved
out of the guide path. Depending on the application, they
may or may not have forks.
One thing automated forklifts and pallet trucks have in
common with AGVs is that they must comply with the
same industry-approved safety standards. In addition to
audible warnings and lights, they have built-in sensors to
detect obstructions and determine whether and when to
slow down or stop to prevent a collision. The sensors,
which may include lasers and camera systems, are positioned so they can detect objects and activity from the
floor to specified heights and distances around the vehicle.
A key difference is that automated trucks offer more
variety. While most are electric, they come in a range of
models, including pallet trucks, counterbalanced sit-down and stand-up forklifts, order pickers, turret trucks,
and reach trucks. They also use a variety of guidance systems, including lasers, vision-based guidance, radio-frequency identification (RFID), and global positioning systems (GPS). In some cases, a single vehicle can operate
with multiple navigation technologies. For example,
Kollmorgen, which provides “automation kits” for AGVs
and fork trucks, says its NDC8 control system works with
all established navigation technologies, allowing a vehicle
to serve, say, a storage area using one type of navigation
and a manufacturing area using another. Regardless of
the navigation method, however, there must be an overlaying system that controls and directs the entire fleet of
automated lift trucks to ensure safe, efficient operation,
says Tomas Angervall, product marketing manager for
Kollmorgen.
Collaboration among truck makers and specialists in
vehicle control systems is common. In Europe, for example, some Toyota Material Handling Europe (TMHE) and
Jungheinrich products use Kollmorgen’s NDC8 control
system, while Linde Material Handling collaborates with
Seegrid Corp., the developer of vision-guided AGVs. In
the North American market, meanwhile, Mitsubishi
Caterpillar Forklift America Inc. (MCFA) is working with
Egemin Automation on a laser-guided, stand-up counterbalanced forklift. The Raymond Corp. has partnered with
Seegrid, and Crown Equipment Corp. supplies forklifts
for Dematic’s Laser Trucks+ voice-directed case-pick system. Nissan Forklift Corp. provides a pallet truck for
Swisslog’s AGVPick product, which also uses
Kollmorgen’s laser-guidance controls.
Not all automated trucks involve such collaborations,
though. Crown’s QuickPick Remote pallet truck is an
independent product. So is Jungheinrich’s RFID-based
Warehouse Navigation semi-automated system for very
narrow-aisle trucks, which is distributed through MCFA’s
dealer network in North America. (See sidebar for a list of
automated truck providers.)
Some automated trucks are directed to the proper location by the operator. Depending on the guidance system
and provider, this is accomplished by means of a voice
system, use of a remote control, or by responding to oper-
