What do you really want? It’s not such an easy question to answer. Even if it’s just a cup of coffee with a friend or a relaxing vacation, what you get is never just what you want, it’s what you plan for. That holds true for fulfillment operations too: You have to consider all the angles before you decide which technologies will work best for your distribution center, keeping in mind that a DC’s efficiency is linked directly to the way in which it applies advanced system technologies. Since the efficiency — or inefficiency — of the DC makes a significant contribution to the organizational bottom line, choosing which of the available technologies to deploy is far from a spur-of-the-moment decision. In fact, how appropriately a distribution facility uses these technologies can determine whether the operation is a success or a failure.
Pick and choose
Beyond a traditional, paper-based (paper) system, the three technologies most commonly used now in distribution centers are radio frequency terminals (RFT), pick/put-to-light (PTL), and the emerging voice recognition systems (voice).
| Function | Paper | PTL | RFT | Voice |
|---|---|---|---|---|
| Receive dock operations | Good | Poor | Good | Average |
| Put away into pallet rack | Average | Poor | Good | Average |
| Each pick from case flow | Poor | Good | Average | Average |
| Case pick from decked rack | Average | Average | Good | Good |
| Pallet pick from pallet rack | Average | Poor | Good | Good |
| Replenish from pallet rack | Average | Poor | Good | Good |
| Ship dock operations | Good | Poor | Good | Average |
A traditional paper operation uses text or numbers on documents to guide operators. RFT systems, which are the most widely used advanced technology, require the use of hand-held or wrist-mounted terminals to direct operators. The terminal screen displays information to provide instructions to the operator.
The use of voice systems is steadily on the rise in case-pick and other traditional DC operations. This technology offers an efficient, hands-free process by converting electronic text into voice commands that inform the operator of each task. An operator wears a headset to receive information via a radio frequency unit secured around his waist.
Pick/put-to-light systems are typically used in open-case/each-pick operations. Location lights guide the operator during picking.
The efficiency of these technologies varies depending on their application. Each of these options can be effective if it is used in the right operation. A thorough review by traditional DC function reveals the various possible uses of each technology, but selecting the most efficient one requires both quantitative and qualitative analysis. The results of a qualitative comparison depend on the weight of each criterion. You should expect to conduct a high-level assessment of qualitative issues to understand the strengths and weaknesses of each technology.
Paint by numbers
A quantitative evaluation should compare the investment and annual operating cost factors of different technologies. A paper-based system is the least expensive to implement. The cost depends on the volume of paper, number of printers, and other equipment required.
| Criteria | Paper | PTL | RFT | Voice |
|---|---|---|---|---|
| Accuracy | Poor | Average | Good | Average |
| Reliability (up time) | Good | Average | Average | Average |
| User-friendliness | Poor | Good | Average | Average |
| Proven technology | Good | Good | Good | Average |
| Supports SKU increase | Good | Average | Good | Good |
| Supports activity increase | Average | Good | Average | Average |
| Ease of maintenance | Good | Average | Average | Average |
| Ease of implementation | Good | Good | Average | Average |
What you can expect to pay for an RFT system depends on the number of terminals or users you require. Figure on an an average cost per terminal of about $2,500.
The quantitative factors for a voice set-up are similar to those for an RFT system. However, the cost of the voice equipment per operator can be $5,000 to $6,000. Furthermore, both RFT and voice systems typically require an RF network to receive and send information. Network cost varies depending on the type of transceivers, Ethernet backbone, and coverage required.
In a PTL system, each location requires a location light display. In addition to the location light, each bay or section includes a digital light display, and each zone usually requires a tethered scanner. Based on 1,500 locations, plus installation and training, an average cost for a PTL system is $360 per location.
Laborious work
The main operating cost to consider when you compare technologies is the labor each requires. The actual throughput results of each technology depend on the DC application, and you will need a detailed productivity analysis to define the annual labor cost accurately for each technology.
Once you identify the most appropriate technology options, it’s time to consider the daily function of each technology, the specific distribution problems you expect it to solve, the technology’s integration with other systems, and its economic feasibility. Considering all of these factors in relation to a specific application will guide you toward a satisfactory solution.
Norman Saenz, Jr., is manager of logistics at logistics design firm Carter & Burgess Inc. of Fort Worth, TX. He can be contacted at (817) 222-8689 or by e-mail at [email protected].