Loading dock automation

Responding is Troy Bergum, product manager for Rite-Hite, Milwaukee.

Technological advancements – such as AS/RS, robotics, AGVs and warehouse management systems – have made industrial facilities increasingly automated. However, despite these 21st-century innovations, many loading docks still rely on manual labor and outdated equipment. Fortunately, new safety- and efficiency-enhancing products such as interlocked and integrated loading dock control systems are becoming more widespread, helping bring dock operations up to technological par with the other process areas in warehouses and distribution centers.

Vehicle restraints fire automatically

At one time, vehicle restraints, levelers and overhead doors were operated manually. For example, workers would need to go outside and physically set wheel chocks on a trailer’s rear tires once positioned at the dock. These types of operations not only were time-intensive, they were potentially dangerous – with a host of potential accidents caused by human error.

Since then, restraints have been developed to automatically secure trailers and trucks, helping docks operate safer and more efficiently. Automatic restraints eliminate the opportunity for mistakes by the driver, ensuring the trailer can’t mistakenly pull away when a forklift is still inside.

Automatic restraints can work by locking on to the trailer’s wheels or, more commonly, its rear impact guard. The most advanced RIG-based automatic vehicle restraints offer a vertical engagement range of 9 to 30 inches. Some models can even help secure intermodal overseas container chassis, which are increasingly common across the supply chain.

Visual dock communication

The traditional red/green signaling system is a familiar fixture at plants and warehouses. Inside, a green light tells the forklift operator the trailer is secured and safe to enter. Outside, the light turns to red, letting the truck driver know that it is not safe to pull away from the dock, as the trailer may still be getting serviced. The lights are reversed when the restraint gets unlocked, telling the truck driver he or she can depart safely. Additional features in the past few years, such as well-placed, instant status-at-a-glance lights at the corners of dock doors and in dock levers, have made work even safer for lift truck drivers.

The next step in automated safety

At many facilities, the various pieces of loading dock equipment are operated independently of each other. Today’s leading loading dock control systems do away with this danger by automating the loading and unloading process by interlocking these individual elements into a safe sequence of operation.

For instance, the most advanced dock control systems can be programmed with a green light interlock, which disables the use of the hydraulic leveler or overhead door until the vehicle restraint is safely engaged; an overhead door interlock, which requires overhead doors to be opened prior to leveler operation; or a stored leveler interlock, which ensures the leveler is stored safely before the restraint can release the trailer. If an inexperienced worker presses the control box button for an individual system element in the wrong sequence, it won’t work – ensuring no safety procedures will be skipped.

Barriers positioned near the edge of the dock door to prevent falls out of the dock opening also can be integrated into this safe sequence of operation. Once the trailer is securely in place, the lock button is pressed, the light on the control box turns green and the barrier releases for easy access to the trailer. The most advanced barriers – made from PVC-coated fiberglass mesh and heavy-duty polyester – can stretch across openings 16 feet and 5 inches wide, and are able to stop up to 30,000 pounds with minimal damage to the barrier.

Like smartphones, these advanced control systems use a touchscreen interface. However, they are also built to withstand the harsh conditions on a loading dock, meeting requirements for electrical noise, electrical and environmental conditions, and chemicals. In addition, they have flexible circuitry and can be modified to update components or add features well after original installation.

The automated dock is coming

As new technologies such as interlocked loading dock control systems continue to emerge, loading docks and warehouses will quickly catch up with internal manufacturing operations in terms of “automating-in” safety, efficiency and comfort. Although many of these systems are relatively new, expect to see them become increasingly common in the coming years.

Note from author: The information herein is provided as a general reference regarding the use of the applicable product(s) in specific applications. This information is provided without warranty. It is your responsibility to ensure you are using all mentioned products properly in your specific application and in accordance with all laws and regulations.

Editor's note: This article represents the independent views of the author and should not be construed as a National Safety Council endorsement.