November 2, 2018
material handling | Fulfillment Systems

Go with the flow to improve fulfillment in the DC

Go with the flow to improve fulfillment in the DC

Waveless fulfillment systems create a continuous flow of orders through the distribution center, answering today's call for more nimble material handling solutions.

By Victoria Kickham

Material handling software and solution providers are fielding more requests for "waveless" fulfillment solutions as DCs respond to increasing pressure to get consumer orders out the door faster than ever before. Driven by omnichannel business trends, "waveless" picking is fast becoming an industry buzzword as organizations seek productivity-enhancing material handling solutions.

"The growth of e-commerce fulfillment has really pushed for change in the fulfillment landscape," says Adam Kline, senior director of product management for supply chain technology provider Manhattan Associates, which offers its Order Streaming product as a waveless technology solution.

"Order Streaming, or waveless picking, has its place in a dynamic, flexible world where DCs must be able to prioritize and reprioritize orders," he says.

In a nutshell, waveless fulfillment systems provide a continuous flow of orders through the DC, as opposed to traditional wave-based systems that produce batches of orders that are released for an entire shift or portion of a shift. When a new order is received in a waveless environment, the order is automatically inserted into the flow of orders being processed, instead of being held for inclusion in a later batch.

Proponents of waveless picking say it gives organizations the flexibility to react more quickly to changes throughout the day—rush orders can be inserted into the mix for faster processing, for exampleand that it reduces downtime and increases order throughput by eliminating the ramping up and down that occurs between waves or batches of orders. What's more, orders can be inserted into the pick path of an order picker to reduce travel time, increasing worker productivity. These are things you can't do with wave picking once the batches are set.

Waveless technology allows companies that operate in less predictable environments—particularly e-commerce retailers—to address today's shorter cycle times and respond more quickly to changing customer demands, says Carlos Ysasi, vice president of systems integration for material handling solutions company Vargo, which offers waveless fulfillment through its Continuous Order Fulfillment Engine (COFE) warehouse execution system (WES). Ysasi adds that advancing technology is another crucial part of the equation, as waveless systems automate the fulfillment process by incorporating software that analyzes orders in real time, allowing organizations to adapt the flow of orders to the DC floor.

"This applies [particularly] to e-commerce, [where] you don't know when orders will come in," he explains. "Having a real-time system that can incorporate new orders into the workstream allows us to seamlessly process all the priority orders."

Apparel and footwear companies were among the earliest adopters of waveless fulfillment systems, but experts say the technology may soon gain acceptance in other industries where speed plays a crucial role in customer satisfaction.

"[Pharmaceutical wholesalers] are one example," says Kline, pointing to that industry's need to adhere to tight delivery windows in shipping to hospitals, for instance. "[Waveless] is certainly a topic of discussion for those types of customers."

Ysasi adds that waveless, continuous flow principles apply to any distribution center, whether it's a fulfillment center for the e-commerce, retail, wholesale, or pharmaceutical industry.

"What's on everyone's minds right now is e-commerce because that's the fastest-growing part of retail," he explains, addng that Vargo has "successfully applied these continuous flow principles in multiple distribution centers across many different industries."


Kline and Ysasi use a push-pull analogy to describe the difference between wave and waveless picking. In a wave-based system, orders are triggered by a schedule—typically, the beginning of a shift. Business rules determine which orders are selected and released, or pushed, in batches to the DC for fulfillment. The system works well in manufacturing and wholesale environments, where large or bulk orders are being shipped to commercial customers. In a waveless system, work is pulled to the DC floor as orders come in and as workers become available to fill them, a system better suited to smaller, more diverse consumer-type orders.

"[Waveless picking] is more resource-aware. You are pulling work down to the floor as resources become available," Kline explains. "[As a result], resources are more highly and consistently utilized over time, so it improves throughput and visibility."

Ysasi emphasizes the efficiency of the process.

"We're not pushing the processes from receiving to shipping. We're pulling, using a resource to pull from shipping to receiving. We're not preplanning, we're not working ahead—we don't have buffers," he explains. "Truly, every process is in balance, and we use triggers to set the parameters to pull to our process. Once we hit those triggers, we release work. These triggers control the flow of work. We are using Lean principles to be able to do this. It's all about pulling versus pushing."

Gary Cash, vice president of solution development for material handling software and controls provider Pyramid, agrees. Historically, he says, building waves has allowed companies to better track and manage orders. But the system also has drawbacks—particularly when it comes to worker productivity.

"In a wave of orders, you start with a bit of work, then ramp up, and then ramp down," he explains, noting that at the end of the wave, there is a lull in the activity as workers wait for the next batch of orders. "When you go waveless, you can create a more constant flow of work."

This is especially helpful in today's omnichannel environment, where distribution center personnel are working to fill a wider variety of orders in a shorter period of time, and productivity is at a premium.

"The highest labor content in a building is usually in the picking area. If we can make that better, we can keep costs down," Cash explains. "And when we get to [the holiday season], organizations have to hire huge amounts of additional people. If we can be efficient and avoid some of that hiring because of improved efficiency, it certainly helps."


Waveless picking is not the answer to every DC's fulfillment goals, and experts urge companies not to focus so much on the new and innovative as on finding a solution that is tailored to their needs. Meanwhile, some systems integrators and software providers offer both wave and waveless solutions, and Manhattan Associates says it has a product that can bridge the gaps between the two. Such flexibility is especially valuable in an omnichannel environment, where an organization may be running retail, wholesale, and e-commerce operations out of a single building, Kline explains. In those situations, managers may want to switch between a waveless system to fill e-commerce orders and a wave-based system for wholesale orders to a large retail customer, for example. He says Manhattan's Warehouse Management for Open Systems (WMOS) 2018 provides this capability. The system also offers flexibility to organizations that may be hesitant to switch from a traditional "hand-to-keyboard" wave mentality to a software-driven, automated waveless process in one fell swoop. He says Order Streaming allows those customers to ease into it by trying it with a few orders before they embrace it completely.

"Every single DC on the planet has run on a wave system—and they may not want to change everything overnight," he says. "We offer the ability to run both, so they can phase in [waveless technology] over time. This allows DCs to ease into the waveless approach and takes some of that change management off the table."

For those ready to take the plunge into waveless, finding the right solution often means incorporating other time- and labor-saving technologies as well. Ysasi says today's trend toward automation is driving much of the change occuring throughout the DC and that the intersection of waveless technology, robotics, and even artificial intelligence will shape the fulfillment landscape moving forward. Vargo is already integrating robotics into its COFE WES, incorporating robotic pickers into its goods-to-person fulfillment systems and working on a variety of robotics/automation projects with large retail customers—all in an effort to become more efficient and productive in a changing business climate.

"[E-commerce companies] are showing the way. You place your order today, you'll get it tomorrow," Ysasi explains. "Order cycle times are going down, so if you go back to batching, it just doesn't work in today's environment [for many companies]. Cycle times need to be 30 minutes, not two hours or all day."

About the Author

Victoria Kickham
Senior Editor
Victoria Kickham started her career as a newspaper reporter in the Boston area before moving into B2B journalism. She has covered manufacturing, distribution and supply chain issues for a variety of publications in the industrial and electronics sectors, and now writes about everything from forklift batteries to omnichannel business trends for DC Velocity.

More articles by Victoria Kickham

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