When you go to buy a printer or a camera these days, you don't have to worry about getting it to work with your PC. You can plug it into your computer and—bingo!— it's ready to go.
Unfortunately, the ease of integration that we've come to expect with our consumer electronics doesn't translate into the material handling world. Although a lot of vendors market their equipment as ready to "plug and play," DC managers can't assume that the new devices they're installing will automatically be able to "talk" to other components of their material handling systems.
Most of the time, DCs find they have to bring in a systems integrator, a specialist that creates interfaces between electronic devices so that they can communicate with each other. Although industry experts say it's much easier to connect material handling equipment to computer systems today than it was 10 years ago, right now, plug and play is still more an ideal than a reality.
Making a connection
That's not to say that all of the plug-and-play claims made by vendors are pure hype. Though the equipment's capabilities are often oversold, there are some cases in which customers can install a new piece of equipment without the need for integration. But those instances are limited to very basic setups. If a warehouse or distribution center simply needs to move a box from storage to the loading dock via conveyor, then it's possible to "plug and play." Indeed, a number of manufacturers make transport-type conveyors that can be set up fairly easily. "The closest thing to plug and play in materials handling is the DC volt [motor] conveyor," says Robert Reinhartsen, an account executive with W&H Systems, a systems integrator based in Carlstadt, N.J.
But few installations are so simple. The typical distribution center today uses an array of sophisticated material handling equipment to get product in and out the door. That equipment runs the gamut from conveyors to pick-to-light systems, from print-and-apply bar-code labeling machines to voice-recognition systems. All of those devices receive their directions from a warehouse management system (WMS), a software application that coordinates the flow of product putaway, storage, and retrieval. "When you get into systems that do complex things, "says Reinhartsen, "you have to design and integrate the equipment."
Still, integration is not the chore it was 10 years ago. Back then, a systems integrator would have to write special interfaces between the WMS and a piece of material handling equipment so that the software could transmit instructions to the device. "A decade ago, it took 14 weeks to get the WMS up and running and another 36 weeks to get all the components connected," says Jack Kuchta, a consultant with Gross and Associates in Woodbridge, N.J. "What's changed is that there's now off-the-shelf middleware to handle the equipment interfaces to a major WMS."
In part, it's easier to connect software systems to automated conveyor and sortation equipment today because of the existence of network communications standards for industrial automation—such as the EtherNet Industrial Protocol (IP), Profibus (for process field bus), and DeviceNet networks. Those protocols enable devices like bar-code scanners, motors, and sensors to exchange information with programmable logic controllers (PLCs). "Every manufacturer used to have its own method for talking to PLCs," says Mike Brinkman, a controls sales manager for Bastian Material Handling in Indianapolis. "We now use standard protocols so it doesn't matter if you have a Siemens or a Dematic conveyor."
Along with these protocols, the industry has seen the emergence of a software application called a warehouse control system (WCS), which sits between the WMS and the material handling equipment. The WCS takes general instructions from the WMS about what products need to be moved and translates that information into specific instructions for a particular piece of equipment. In essence, says consultant Sam Flanders, president of 2wmc.com, a material handling consulting firm in Portsmouth, N.H., the WCS serves as an integration platform on which to connect the different kinds of equipment.
Despite these technological advances, the industry is still a long way from plug and play. Why is that? Experts in the field say that given the enormous variation from one DC operation to another, it would be impossible to create a one-size-fits-all software package. Some customization will always be required. "The backbone of the system is software, and there's no product that comes in a box all wrapped up in cellophane," says Steve Martyn, chief executive officer of GRSI, a systems integrator located outside Philadelphia.
Nowadays, it typically takes between eight and 12 weeks to install a piece of material handling equipment in a distribution center, says Martyn. As part of the project, a company has to develop a "functional document," a spec sheet that spells out what has to be done in terms of integration. Once the specs are written, Martyn says, an integrator can use existing software templates, but it still has to write specific coding instructions for at least 40 percent of the integration.
It's essential that a company define the transaction format—the method of exchanging data between the computer application and the equipment. Flanders says that the format will specify the information required for the equipment to do a task—an item's order number and quantity, at a minimum— and then determine what information the equipment will send back to the computer when the job is completed. "It's not like installing software on your computer," Flanders notes. "You have to define the transaction format. You have to get data into a format that's understood."
No industry consensus
Before plug and play can become a reality in the material handling world, the industry would first have to agree on a set of standards for data exchange—standards that software and equipment makers would be required to follow. That's not an impossible task; after all, players in the computer and electronics industry were able to agree on the Universal Serial Bus (USB) as a standard for interfacing devices with computers. But it's one that would require leadership. "The only way to have true plug and play is if you have a body of industry leaders that define a standard," says Daniel Ahrens, a client support manager at Fortna Inc., a material handling consulting firm and systems integrator based in West Reading, Pa. "This is the standard for WMS and will consist of this message type. Anyone who wants to participate would have to adhere to this standard."
But unlike the consumer electronics sector, the material handling industry has yet to show much interest in promoting common interface standards. "The trouble with standards is you have to get hundreds of companies to agree," says Flanders. "You have to have a driving force to make this happen. And nobody thinks it will result in extra revenue."
Although there's no pressure on the material handling industry to develop common standards right now, that could change. The ranks of warehouse management software providers are dwindling in the face of competition from enterprise resource planning (ERP) system vendors like SAP and Oracle. If the large software houses come to dominate the supply chain software market, they might take it upon themselves to set de facto standards that material handling vendors would be forced to meet. "The big ERP guys probably will eventually set standards," says Martyn.
But as long as companies want their DCs to be unique, companies installing sophisticated material handling equipment will still need the services of systems integrators. "For plug and play to work, it would have to start at the top," says Pratap Chakravarthy, a project manager with Accu-Sort Systems Inc. in Philadelphia. "Every customer would have to have a standard ERP, a standard WMS, and a standard WCS, and each industry would have to have standard operation, which is almost impossible. A lot of customers pride themselves on differentiation, and [they view their DCs' unique capabilities] as a competitive advantage."