Next-gen Warehouse Operations Start with Next-gen Wireless

Summary

As a critical part of logistics supply chains, warehouses are under increasing pressure to increase their productivity and resilience with next-generation technologies like automation, Internet of Things (IoT) and digital twins. These promise to boost productivity, address labor shortages and improve data transparency. They also enable more flexible and reconfigurable automated systems that cost-effectively address e-commerce and the complexity that results from the proliferation of stock-keeping units(SKUs).
 
Implementing these next-gen warehouse technologies, perhaps unsurprisingly, also requires next-generation communications. The performance requirements of the newest automation technologies, for instance, go beyond the capabilities of Wi-Fi. Private wireless communications based on more robust and secure technologies like LTE and 5G are needed to meet the need for high-speed, low-latency and mobile connectivity. Unlike Wi-Fi, they can be engineered for predictable performance and tuned to the specific needs of each use case.
 
In short, there’s no point in upgrading to Industry 4.0 applications such as IoT, robotics and automation if your existing network isn’t up to it in terms of performance and scalability.
 

Warehouse 4.0

The pandemic accelerated many of the drivers for digitally transforming logistics operations, sometimes referred to as Warehouse 4.0. Supply shocks and supply chain issues had everyone in the industry scrambling for solutions to remedy worker shortages, better transparency to understand where goods were being held up and better guidance for businesses and retailers to help them with their planning and customer communications.
 
While pandemic-related supply chain issues have eased to some degree, the issue of skilled worker shortages continues, largely because of demographics and the aging of the workforce, especially in developed countries. The drive to automate more aspects of the logistics industry is in response to these critical shortages. E-commerce and the proliferation of SKUs are also calling for more flexible and adaptable automation solutions.

Next-gen automation

The earliest forms of automation tended to use fixed infrastructure such as conveyor and sortation systems, overhead pouch systems and pick-n-place robots for both palletized and non-palletized goods. These systems worked well when they were purpose-built for a specific business and its central warehouses.
 
Along with the growth in e-commerce, the need for more flexible systems is particularly true for third-party logistics (3PL) operators at the edge of the distribution network. In terms of automation, they need to be able to rapidly adapt as inventory changes and new contracts introduce goods with different sorting and retrieval requirements.
 
A degree of flexibility is achieved by arming manual pickers with handheld scanners to interact with automated data collection systems using barcodes or radio-frequency identification (RFID) technologies. But as many warehouse operators have experienced, making e-commerce profitable this way is hard. The preferred solution is more mobile technologies, such as automated mobile robots (AMRs), which make it possible to build flexible, distributed automated storage and retrieval systems (AS/RS) systems. Amazon’s Kiva AMRs provide a template for the kind of automation systems warehouses now require.
 
A distributed AS/RS often uses AMRs that self-navigate the warehouse, guided by cameras, sensors, location positioning and Fleet Management. The most advanced AMRs dynamically adjust their routing to avoid collisions; use artificial intelligence and machine learning to recognize people, machines and trajectories; and optimize batches and pick paths on the fly. When tied into digital twin software, it becomes possible to use predictive analytics to coordinate AMRs, manual pickers and other sorting and retrieval systems for end-to-end optimization.

Next-gen wireless

Early mechanical AS/RS systems used cables for power and data connectivity, which made them very reliable but limited their flexibility. Reconfiguring these kinds of systems involves pulling cable, which is expensive and time-consuming. With the advent of light, powerful lithium batteries and high speed, low-latency wireless connectivity, an entirely different approach to AS/RS becomes possible.
 
The introduction of AMRs can improve the overall material handling throughput of the warehouse.  However, their productivity is often not what it could be because the predominant wireless technology used for connectivity is Wi-Fi. There are several issues with Wi-Fi, but the primary one is that it doesn’t support mobility above walking speed. When AMRs and people are mixing in the warehouse, this is safer, but for fully automated warehouse AS/RS systems, like the Orodo grid, faster speeds are necessary to make truly significant improvements in productivity—this requires using industrial-strength private wireless.
 

Wi-Fi limitations

One of the technical problems with Wi-Fi is that as a device roams from one access point to another. There is not a robust, signaling procedure for handing off a device from one access point to another. Wi-Fi-based AMRs often stall because they lose network connectivity at the handoff between access points. This can cause delays of 10–15 seconds, or worse, require a reset on the floor to establish connectivity. Industry Institute of Electrical and Electronics Engineers (IEEE) standards such as 802.11r, 802.11k, and 802.11v address some of the roaming issues but these are optional capabilities and don’t provide seamless handovers.
 
Wi-Fi poses other problems as well. A single access point (AP) can only handle 30-100 active connections with significant degradation in performance when exceeding 25-30 devices vs. LTE and 5G, which can support up to 800 simultaneous connections without any degradation in performance. It should also be noted that Wi-Fi doesn’t have a robust IoT device eco-system.
 
But the modern warehouse uses a lot of IoT devices. LTE has a broad device eco-system, and 5G’s IoT device eco-system is growing rapidly. Thus, an LTE or 5G network, unlike Wi-Fi, can communicate with hundreds or, even, thousands of devices at the same time. This includes everything from tracking assets, sending positional data and directing AMRs to streaming video from remote-controlled lift trucks and sending augmented reality information to and from pickers wearing heads-up displays.
 
Much less secure than either LTE or 5G, Wi-Fi also requires more access points to achieve the same coverage. Radio technology isn’t as good at managing the kind of interference that metal shelves and other structures create, and Wi-Fi performance is best-effort—there’s no QoS (quality of service) mechanism for assuring that specific parameters are met. This means that if your automation application requires consistent low latency, that cannot be assured. If it requires high bandwidth, it is also a problem. This lack of predictability makes it unsuitable for business-critical systems.
 
Note that Wi-Fi is adequate for many tasks where best-effort service is sufficient. Whether emailing worksheets, messaging a colleague or looking up information on a local Sharepoint server, Wi-Fi is perfectly suited to office-level tasks.
 
However, the next-generation digital warehouse requires ubiquitous, predictable coverage. There can be no holes or breaks in service, since the digital twin has to accurately reflect the state of play at a given moment. 5G is designed as a multi-access network, and a 5G core network can use 5G NR or Wi-Fi access points, as well as interfacing with specific wireless IoT network technologies. The goal is not to decide between these technologies, but to choose the most appropriate technology based on the use case or application.

Summary

Solving the supply chain and logistics problems that cropped up during the pandemic is one of the principal drivers towards digital transformations. Warehouse 4.0 has the potential to make supply chains more information-rich and transparent for clients on both ends of the chain. It can also make operations more productive, safe and secure, and it can address the labor shortages that currently plague the industry.
 
Advanced automation systems, IoT, digital twins and other technologies all rely on ubiquitous, reliable and secure connectivity to realize their potential. This kind of connectivity cannot be supplied by Wi-Fi alone. It is not designed to ensure the performance parameters, it doesn’t support IoT devices, and it can’t manage the mobility of AMRs, autonomous lift trucks or any devices moving faster than walking pace.
 
Therefore, to implement these next-generation technologies, the industry will need to embrace next-generation private wireless systems based on LTE and 5G. Only they have the robust capability to power warehouse automation and support mobility, coverage, predictable performance, quality of service and security with business-critical connectivity.