Delivering fresh food at its peak is what Associated Food Stores (AFS) is all about. From its distribution center (DC) in Farr West, Utah, this wholesale grocery distributor ships approximately 600 truckloads every week to hundreds of grocers across eight states.

Not only is it tough to coordinate the movement of those trailers but margins are thin in the grocery business. "We only cover operating expenses when trailers are moving over the road," says Tim Van de Merwe, internal logistics manager.

To get trailers turned around as quickly as possible, AFS needs total visibility of the equipment at all times in real time. Late this summer, the distributor installed a real-time locating system (WhereNet 408-845-8500 www.wherenet.com) to do just that. Now, AFS can access on demand real-time location information for each of the several hundred pieces of equipment.

The real-time locating system (RTLS) is based on radio frequency identification tags, multiple antennae mounted strategically in the 600-acre yard, and location processors. About 600 tags are permanently mounted on the company's own trailers, tractors and dollies. An additional 400 tags are temporarily mounted on independent trailers that AFS also uses for its shipments.

Already there are benefits to the system. Shipments need to be matched with equipment. Knowing the whereabouts of equipment allows for better routing efficiency in the yard and at the DC. If a match can't be made with available equipment, an alert notifies the system to watch for the next arriving trailer for that shipment.

Better management of equipment also reduces the need to buy or lease additional equipment to process daily shipments. In past years, AFS had to lease 80 to 120 additional trailers for several months to keep up with peak shipment periods. During a case-lot promotional sale a year ago, AFS leased 40 extra trailers. During the same promotional sale this year, volume was up, but the number of leased trailers was reduced to just five. And instead of leasing them for months, the company needed each trailer for just two runs.

In addition, operating costs are greatly reduced since the need to conduct manual yard inventory searches is eliminated. The previous method of locating equipment required an employee to almost continuously walk or drive through the yard to mark down equipment identification numbers and then manually enter the data into a computer. Furthermore, the RTLS has raised tracking accuracy to 100%, a significant improvement over the manual collection of data that ran only 70% to 90% accurate.

Expected payback for the system is 9 to 12 months, says Van de Merwe.

As soon as a trailer enters the yard, it can be tracked by the RTLS. A special proximity communication device located at each gate causes the tag mounted on each trailer to send an initial signal, announcing that particular trailer has arrived. Meanwhile, drivers park the trailer in any available spot in the yard, unless instructed otherwise.

Every 4 minutes after the initial signal, each vehicle's tag sends out a new signal, which updates the system. All signals are broadcast at 2.4GHz and are a 32-bit identification number for that particular trailer. The location is determined when the RTLS triangulates the x,y coordinates of the signal picked up by any of the 19 antennae in the yard that are within range. Antennae are placed every 750 feet. The tag identification number is matched with an equipment identification number, which is tied to a trailer type in the fleet directory.

The RTLS can determine the location of yard resources within 10 feet of accuracy, but Van de Merwe has experienced accurate results at much closer ranges.

"Some testing has proved accurate location results within 12 inches consistently," he notes.

AFS employees then track the location and status of equipment in the yard by viewing a graphical site layout on one of the facility's computers. Every piece of equipment appears as a dot on the screen. Colors designate specific equipment types. For instance, a blue dot represents a trailer, a green dot is for a tractor, and a red dot for a dolly.

To view the equipment identification number, users simply drag the cursor over the dot. In addition, the status of the equipment is represented by the color of the outline of each dot. This provides AFS employees all the information they need to identify and call up equipment as needed. Furthermore, the system identifies the status of equipment in real time. A red outline signifies that a move is pending, green signifies a trailer is available, and a solid fill signifies the trailer is loaded.

When a trailer exits the yard gates, an immediate time stamp of departure is relayed back to the RTLS. If a trailer does not depart on schedule, AFS notifies the trailer's first delivery stop that the delivery will be late. An accurate time of departure can also be used to determine projected return times. If a trailer does not return at its expected arrival time, an alert will signal that another trailer must be assigned to the late trailer's next shipment to avoid late deliveries and demurrage disputes.

The system also has capabilities to monitor the temperature inside refrigerated trucks. After conducting a pilot test of this feature, Van de Merwe says AFS' refrigerated trucks are being equipped with sensors that transmit the temperatures of the frozen foods and produce compartments.

The system sends an alert if temperatures exceed specifications, which will reduce food spoilage. The RTLS can also monitor fuel levels and whether the trailer doors are open or closed, which will greatly reduce shrinkage.

Van de Merwe has other plans for the RTLS. He says the data capture method will not change, but better methods of using collected information are needed.

"The side that needs to improve is how we apply the information. The challenge is developing a reporting structure to use the information as quickly as we receive it," he explains.

In addition, AFS is looking at taking the system, which is now used only in the yard, into the DC. And to improve customer relations, AFS expects to soon provide retailers visibility into the system so they can track the status of their trailers.

"We are in the battle for not only marketshare, but membership, and we want to have an edge. It shows good management to be able to say, 'I know exactly where your load is, I know the status of your load, and I know when you will get it'," says Van de Merwe.