techwatch
let your equipment do the walking
FOR YEARS, DISTRIBUTION CONSULTANTS HAVE LABORED TO
find ways to reduce travel time in the warehouse operation. Traditionally,
that’s meant designing distribution center layouts to minimize the distance order pickers had to walk to retrieve items from storage. Common
sense dictates that the less time workers spend traveling, the more time
they’ll have for order picking and the more productive they’ll be.
But there’s another way to increase picking productivity. Instead of
merely reducing travel distances, some companies are opting to eliminate travel time altogether. They’re doing this by using automated material handling equipment to deliver items to order pickers who remain in
a fixed spot. It’s a concept dubbed “goods to person,” and a number of
material handling equipment manufacturers are touting it as a way to
improve warehouse productivity.
Goods-to-person order picking isn’t a new concept.
Consultant John Hill of TranSystems says the idea has
been around since the late 1960s under various names,
including “goods to picker.” But the concept is attracting renewed interest today as more distribution operations grapple with the challenges of picking individual items, or “eaches,” instead of full cases or pallets.
As for the equipment used in goods-to-person picking systems, there are a number of options. For example, some companies use automated storage and
retrieval systems (AS/RS) with shuttles to deliver
goods to workers. In this type of application, the automated storage and retrieval system uses cranes and
conveyance vehicles to remove pallets, totes, or bins
from storage racks and ferry them to a station at the
end of an aisle. Once the containers arrive at the station, a worker retrieves the items needed and deposits them into the
appropriate boxes or totes to fill customers’ orders. Automated storage
and retrieval systems designed for goods-to-person picking are available
from such well-known vendors as Dematic, HK Systems, Knapp
Logistics and Automation, and Witron Integrated Logistics.
Another option is to use carousels in conjunction with automatic
extractors. Under this approach, the carousel spins to where the desired
container is stored and presents it to the automatic extractor. The extractor, which resembles an elevator, then pulls the container from the
carousel and deposits it on a conveyor for transport to the pick station.
One of the leading suppliers of this type of equipment is Schaefer
Systems International.
Perhaps the newest variation on goods-to-person order picking
involves the use of robots. With a robotic order fulfillment system, a
robot carries products stored on portable shelves to an order picker. Kiva
Systems is the best-known vendor of this type
of technology.
Editor’s note: Dematic’s white paper, “Goods
to Person” Order Fulfillment, can be downloaded
for free from DC VELOCITY’S Web site. Go to
http://www.dcvelocity.com/whitepapers/.
