The Growth of AMRs in Warehousing

COVID-19 has been a significant factor in the accelerated growth of automated systems deployment within our warehouses. This article is a review of the systems currently in operation with companies who have seen this growth in online sales.

I recently attended my third webinar on goods to person automation systems. Suppliers including Körber, Grey Orange, Swisslog, Eurotec, Locus Robotics, Geek and Fetch Robotics were featured in these presentations.

When writing the third edition of Warehouse Management, many of these systems featured as part of the future of warehousing. Now, these systems are well and truly integrated with today's technology.

These systems fall into two categories:

1. Goods to Person (GTP) - Shelves, roll cages or tote bins are transported from their storage location to a picker who is prompted, usually by a pick to light system or via a screen at their workstation, to pick the item and either deposit it onto a pick wall, onto another Autonomous Mobile Robot (AMR) for transfer to another operative or direct to the despatch area.
   
   In Swisslog’s Autostore system which operates with a self-supporting aluminum grid, with AMRs travelling along the top of the grid, items, once retrieved from the storage tote are placed into another tote for transfer. Asda introduced one of the largest Autostore systems into one of their warehouses for their small case items.
2. The second system features a zone pick operation where the AMRs are directed to a zone where a picker picks an item from the storage location and places it on the AMR’s shelf or into a tote. The AMR is then directed to the next pick location, or, if the order is completed, to the packing or despatch area.

Goods to Person (GTP)

In the GTP system, AMRs transport a storage medium from the storage area to a static location where an operative is waiting. In this system, the AMR are capable of independent navigation around the warehouse through mapping and/or utilizing 2D or QR barcodes located on the floor of the warehouse.

Communication is via Radio Frequency (RF). This system has many advantages but also a few drawbacks. The utilization of floor space by these AMRs is high because of their ability to move omnidirectionally, thus reducing the aisle space required in the storage area.

However, unless the storage area is in a low height facility then cubic space is not fully utilized. This can be overcome by operating with multiple mezzanine floors and a lift system as seen in Sodimac’s warehouse in Chile – a system provided by Grey Orange.

This system can also increase productivity up to four-fold as it is the AMRs that travel to the storage areas and to despatch once the orders are completed, not the pickers. It has long been acknowledged that travel takes up to 50% of the time in a manual pick operation.

A potential drawback of the increase in productivity, with operatives handling an increased number of items during the day, is that recent studies in Amazon warehouses that use a similar system, provided by Amazon Robotics (previously Kiva) show increased absence through muscular injuries. Amazon, however, refutes these claims.

Zone Pick Operations

The second type of system features AMRs which travel to a zone where operatives are waiting. Items to be picked can be communicated to the picker via voice commands or a screen on the AMR. This type of system provided by Locus Robotics has recently been installed in the Boots warehouse in the UK.

In this type of system, the crucial aspect is the utilization of the pickers. The pickers need to be dynamic and move between zones if required. In many of today’s automation systems, control of these operations is in the cloud and utilizes Artificial Intelligence (AI) to ensure the system runs as efficiently as possible. The increased use of AI will ensure that items are placed in the most effective location based on the sales data received.

Advantages and implications

Some of the advantages of these systems over traditional automation include the following:

These systems also enable deployment around obstacles such as roof columns.

Many of these systems also provide their own standalone warehouse management systems so that interfaces are reduced. Nigel Lahiri from Grey Orange introduced his software, called GreyMatter, which includes real-time planning and scheduling, continuous order flows as opposed to wave picking and machine learning capability resulting in the efficient deployment of the robots and the storage mediums.

The implementation of these automated systems can also overcome a number of the challenges faced by companies today, namely staff, space, segregation and speed.

These challenges include a shortage of warehouse operatives. A recent CBRE report suggested that significant growth in e-commerce could result in a shortage of up to 452,000 warehouse staff in the US. We are also seeing a significant take-up of warehouse space resulting in less overall space availability. These systems require significantly less floor space than current manual operations.

In addition, COVID-19 has resulted in the need to segregate staff within the warehouse. These GTP and zone pick operations allow this to happen.

Consumers are now demanding faster fulfilment and this puts more pressure on warehouse operations. Next, the UK retailer, for example, now offers next day delivery for orders received up until midnight which reduces the pick time significantly. 2020 has seen a significant increase in the deployment of these automated systems. One of the challenges to come, I’m sure, is whether the suppliers will be able to keep up with demand!