The Evolution Pick of Light Systems

In a warehousing environment, you can count on several stalwart types of equipment in just about every facility. Racking, for one, is ubiquitous. Lift trucks, conveyors of some sort, and dock equipment are all pretty much a given. While pick-to-light came on the scene more recently than these types of equipment, it’s been around long enough now to join the list of “expect to see” technology when you enter a warehouse.

And for good reason. Pick-to-light systems have proven their value over the years. They are convenient for your workforce—employees need only stand in front of their stations, pick the appointed item, confirm it, and move on. These systems reduce walking and increase efficiencies. The ROI on pick-to-light is quick, and the business case is easy to sell.

When you dive into light systems technology today, you’ll find that much of its basics remain the same: There’s beauty in its simplicity. But pick-to-light hasn’t remained static over the years, either. As with all technology, it has evolved; and today, it provides flexibility and integration with other technologies.

“Pick-to-light continues to evolve with changing needs and priorities,” explains Joe Pelej, director of marketing at Matthews International. “You can deploy the systems with ease, and its agility allows it to work in multiple applications.”

The movement to e-commerce has increased the value of pick-to-light, too. “The number of orders has increased, and the sizes have decreased,” says Bob Kennedy, principal at RCK Consulting. “Pick-to-light is well suited to that. It allows for speed with accuracy.”

While today’s pick-to-light isn’t your father’s pick-to-light, it still maintains shades of its predecessors, with a bit of Gen Z tech savvy thrown in.

Better basics

One thing that has changed over the years since pick-to-light came on the scene is its hardware. Today’s units are more robust and offer features their predecessors lacked.

One such advancement is multi-colored lights, for instance. “With additional colors, you can put multiple pickers into one zone,” says Pat Hanrahan, vice president of business development at The Numina Group. “The software assigns operators to a pick area, and they each get a specific color to follow.”

A big advantage to the multi-colored lights is the flexibility it delivers. If you’re busy one day, you can expand the zone and the colors that will be lighting up. A slow day and you compress back down to just one color.

“Many operations have peaks and valleys, with big spikes in throughput from time to time,” says Douglas Card, director of systems and integrator sales at Kardex Remstar. “If you design a system to run with a set number of pickers, it can get expensive. Multiple colors allow you to flex your labor, adding and taking away as needed.”

The performance of the lights is more capable all around today, too, he adds. “The lights themselves are better and can support faster environments.”

Another advancement is improved sensor technology. The equipment can now detect a hand entering a pick position and eliminates the need for push confirmation. If you need to increase the validation quotient, you can combine the pick-to-light with wearables, scanners, and the like.

“This allows you to display additional information to drive higher accuracy with scan validation,” says Hanrahan. “You’re both picking and validating in the same location, then putting directly into the shipping carton or tote. This represents a big accuracy improvement over the last five years or so.”

This combination of pick-to-light and bar code scanning allows you to almost eliminate secondary checking, too, according to Hanrahan. The result is higher order fulfillment pick, pack, and ship productivity.

Numina’s customer, United Medco, added in hands-free bar code scan validation in its optimized zone routing pick to conveyor system. With that combination, the company increased picking accuracy to 99.8% and boosted pick rates to 300 lines per hour.

Additionally, the company was able to eliminate the need for employees to read pick tickets, which has helped with onboarding the company’s multi-lingual workforce. This allows workers to be productive right out of the gates.

Other hardware advancements include touchless photo sensors, something Matthews International’s Pelej says reduces movement and speeds up the picking processes. “When an operator breaks the plane of light, the pick is recorded,” he says. “When you couple that with bin illumination from overhead, you get extra visibility and accuracy.”

While lights systems have held most of their market in the warehousing space, they also have growing applicability in manufacturing. Matthews’ “Build2Light” system is an example.

Using the same hardware as its pick-to-light system, the Build2Light system is a standalone system that allows users to configure their own part-specific builds. Matthews says the system can work with kitting, Kanban assembly, line sequencing and build-to-order applications, among others.

Software assist

Complementing the advancements in hardware are advancements in software. “That’s what’s really key,” says Pelej. “Software enables the pick-to-light to expedite orders and integrate with other technology. It’s the differentiator.”

The software, which integrates with warehouse management systems (WMS) or warehouse execution systems (WES), can allow companies to drill down to the zone level and employee level views, allowing pickers to operate proactively. “It can offer things like dashboards that provide real-time statistics on any area using that picking system,” says Hanrahan.

Software sophistication also allows for light-enabled batch picking carts that allow associates to batch pick multiple orders into totes, reducing travel time. They then move to light-driven put walls, where employees can scan and sort individual orders. This is a great example of two types of software integrating together—WES and the pick software.

“The advent of WES and other middleware tools has made pick-to-light more flexible,” says Kennedy. “Its lack of flexibility was always its limiter in the past.”

Better software also means better integration between pick-to-light and other automation. “Customers have expanded to multi-modal solutions and one platform can easily expand into many uses,” Kennedy says.

Hanrahan points to a case where an integrated sortation system can allow sorting at a consolidated put wall. “This reduces the number of destinations and reduces costs,” he says. “Then the employee packs the orders out and integrates it directly into the inline packaging automation.”

Light systems can also work with batteries and mobile devices of many types—you can even receive updates from mobile apps, allowing people to move about the warehouse as needed. This flexibility means that lights can work in a variety of less traditional places. Mobile carts are one such place, as are totes. Pelej says that Matthews has done thousands of such applications.

Card says that today, “you can see, pick and put in virtually any location,” he says. “Light systems have moved well beyond flow racks and that increases speed and accuracy.”

Taking things a step further, these applications can also extend to autonomous mobile robots (AMRs) that work as co-bots. “In some cases, we can engineer specific tops to attach to AMRs,” says Pelej. “The AMR can come to the employee and project lights that direct them in pick or put tasks.”

New, higher capacity AMRs are also getting in on the light action, says Hanrahan. “They can carry up to 1,500 kilograms and that saves your workers from having to manage big loads manually,” he explains. “They can move more items to the put wall and reduce walking paths.”

Despite all the software, hardware and integration features, light systems remain one of the most affordable types of technology to implement. The systems come with a low cost of entry when compared to other types of automation, and they also deliver a rapid return on investment. Their use case is well established, too, so obtaining a green light on the spend is generally an easy lift.

For all the advantages, as with all technology, the question of how AI might enhance—or eliminate—light systems is one to address. Light systems are still dependent on human interactions, which can still lead to errors, even with secondary validation from bar code scanners and the like. There could be a role for AI to improve on that propensity at some point in the future. As AI evolves, expect to see it integrating with lights systems, and one day maybe even eliminating it. For now, however, that remains in the distant future.

As automation options increase, it’s easy to believe light systems may go by the wayside in the future. But no one is counting them out yet, and as they’ve continued to adapt and add improved hardware and software, they’re proving their mettle in the modern warehouse.

“The drive from e-commerce means that light systems are more useful than ever,” says Kennedy. “It’s a sound, proven technology that offers many advantages.”