Exploring the Goods-To-Person Technology Options, Part 1: Mobile Automated Vehicles

Goods-to-person (G2P) technologies come in all shapes, sizes, and flavors these days as vendors offer an ever-greater variety of solution types. We’ll explore the differences in this post, but first, let’s review what they all have in common: they bring products to an order fulfillment associate who first picks the required item(s) from a bin, pallet, carton, mobile cart, tray, tote, or other storage container, then sends the container of remaining product away.

The majority of G2P solutions use multiple designated workstations for picking, replenishment and quality checks, eliminating the need to walk to the product locations. As I’ve written about before, it’s been estimated that – in a conventional warehouse – as much as 70% of a picker’s time is spent traveling from one pick face to another. The ensuing boost to productivity, efficiency, and throughput makes G2P technologies an appealing solution for facilities filling multiple orders of individual items, such as those in e-commerce.

Where G2P solutions differ are in the design and function of the technologies themselves. Very broadly speaking, there are two primary categories of G2P systems: mobile automated vehicles and automated storage and retrieval systems (ASRS). Within each of these categories there are a variety of different technologies and solutions. Each offers unique advantages to an application based on factors such as:

• Characteristics of the handled items, such as dimensions, weight, environmental requirements (ambient, freezer, refrigeration), conveyability with or without a storage container
• Quantities and varieties of products to be handled
• Velocity, or order frequency, of each item
• Number of orders filled in a day
• Average and peak throughput rates
• Available space within a facility

In this, the first of two posts, we’ll take a closer look at MAVs used in G2P applications; in the next post, we’ll explore the ASRS options.

Mobile Technology Offers Layout Flexibility

Generally speaking, the MAV category of G2P technologies can be sub-divided into three types of solutions (and, notably, the distinctions between these technologies are rapidly blurring as navigation technologies and maximum payload sizes and capacities evolve):

• Autonomous Mobile Robots (AMRs) that assist with fulfillment by moving product from one location to another. They typically transport lighter payloads of individual totes or cartons and navigate freely among their human colleagues and around obstacles with no safety barriers. G2P AMRs retrieve items or storage containers of items from racking or conveyor and deliver them to one or more order fulfillment workstations. (These differ from aisle pick AMRs, which pause at a shelving location and wait for personnel to pick or put an item on the AMR before traveling to another location.) When a G2P AMR arrives at a station, a display indicates how many items should picked or put to fulfill an order.

• AMRs that tunnel under a payload – such as a pallet, rack or multi-tiered shelf system that holds cartons or totes of individual products – and deliver it to personnel. These systems are frequently protected by safety barriers that only permit authorized staffers to work within the guarded area. Workstations are placed at the perimeter of the guarded area and are often designed to flexibly accommodate a variety of tasks, such as inventory, picking, replenishment and quality control.

• Automatic Guided Vehicles (AGVs), a broad category that also includes automatic guided carts (AGCs) that are low platforms that tunnel under a load and autonomously operating forklifts, that move larger, heavier payloads. In G2P applications, AGVs are often used transport pallets of product from storage for replenishment of forward pick zones or direct picking off the pallet.

From a cost versus performance perspective, the three types of MAVs tend to be on the lower end of the cost spectrum across G2P solutions. This – combined with their inherent flexibility granted by their mobility (in comparison to fixed conveyor or sortation equipment) – plus the ability to easily add more MAVs as needed to support a peak season, often makes them appealing to fulfillment operations.

Further, MAVs can be engineered to function reliably in different environments, including freezers and refrigeration. They can also be equipped with a variety of accessories beyond a simple shelf or platform to hold a carton or tote. These include compact shelving or put wall-style cubbies, articulating robotic arms for gripping and picking, or a roller or belt conveyor top that interfaces with sorters or conveyors to receive or transfer a load.

One potential drawback of MAVs is that their successful use does require a minimum amount of square footage to accommodate a line of MAVs waiting to present their tote or carton to a picker. A facility also needs to dedicate space for the appropriate number of picking stations to meet desired throughput objectives. Therefore, an operation with limited floorspace might not be the ideal application for this G2P solution.

In our experience, fulfillment operations with a high number of individual SKUs and a larger building footprint – but lower order volumes – are likely to find MAVs to be a cost-effective and efficient G2P solution.

Stay tuned for Part 2 of this series, exploring the ASRS options for G2P applications.

Let us bring ideas for improving order fulfillment efficiency and productivity with automation to you. To learn more about working with DCS, connect with us.

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Author

Drew Thomas, Senior System Sales Consultant,drew@designedconveyor.com

A 20-year veteran of the material handling industry, Drew has experienced many different roles – engineering, project management, business development and sales consulting. Leveraging his background in controls automation and his passion for technology, Drew has continuously sought to push innovation in the industry. He cares about making the world a better place by improving the life of others through automation. Outside of the office, you will frequently see Drew on the golf course or exploring the great outdoors with his family.