The world of automated warehouse vehicles can be confusing.  Just consider the various types of available guidance systems: wire-guidance, magnetic tape and magnetic paint, laser-guidance, inertial navigation, and camera based imaging (i.e. vision-guidance).  When you factor in the type of vehicle, e.g. tugger, unit load, custom, etc., the task of selecting a specific platform can be overwhelming.  Nevertheless, with some basic knowledge of automated vehicles, and an understanding of a facility’s material handling processes, physical characteristics, and people, one can quickly identify the most useful and cost effective solutions.

Automated Warehouse Vehicles

Automated vehicles that operate within warehouses go by many names.  Vehicles that navigate via vision, for instance, are often referred to as vision guided vehicles (VGV), and those with laser guidance are often called laser guided vehicles (LGV).  Creating more confusion, some people even call these vehicles mobile robots.

The Material Handling Institute (MHI) has been analyzing AGV use for years, and they prefer this definition: “An automatic guided vehicle system (AGVS) consists of one or more computer-controlled, wheel-based load carriers (normally battery powered) that runs on the plant or warehouse floor (or if outdoors on a paved area) without the need for an onboard operator or driver.”

This definition is useful because it focuses on the system and not just the vehicle.  Although the vehicle, as it automatically moves products form one point to another, is the most visible part of the system, it is only one component of it.    Without software, wireless communications, a user interface, and a battery charging system, the AGV is nothing more than metal on wheels.

Material Handling Process (MHP), Facility Environment, and People

Your Product

When specifying automated warehouse vehicles, remember to “always keep the most important thing as the most important thing,” which, in any MHP, is the product being handled or transported.  There are many types of AGVS vehicles, but, no matter how advanced a particular AGVS may be, if its vehicle cannot transport the thing that needs to go from A to B, it is useless. For instance, some vehicles are designed to accommodate small loads less than 500 pounds.  A larger, heavier item would crush this vehicle, but a tugger (or towing vehicle) that pulls the item on a trailer, would move it with ease.  Other types of AGVS vehicles include unit load vehicles, pallet trucks, fork trucks, and many more.  It is a long list, but, by never losing sight of the payload, the list is quickly reduced to the few most promising options.

Navigation

Once the proper vehicle has been selected, we need to look at the environment it will navigate in.  For example, due to their low cost, many organizations are attracted to systems that navigate by sensing magnetic tape embedded in, or applied on top of, the facility’s floor (although this may introduce strict floor specifications that could add cost if floor modifications must be made).  Unfortunately, this makes it difficult to create new or different routes in a dynamic facility whose layout and operations change frequently. It may also be tempting to buy a system that operates via vision because, since it navigates via landmarks (like people), it is very flexible; however, it could also be more costly.  Thus, selecting the right navigation system is a balance between cost and capability.  Facilities with layouts or processes that rapidly change may require the flexibility of more advanced systems, such as vision, while customers with more stable layouts and processes may be able to use a less costly and less flexible technology.

Maintenance

The systems support structure (i.e. battery charging, parts storage, and maintenance) is the next critical decision.  The AGVS battery charging system adds equipment and space, which adds cost.  Some systems are more energy efficient and occupy a smaller footprint than others, but that could come at the cost of capability. Likewise, parts storage and maintenance must also be considered.  Regular preventative maintenance tasks will need to be performed, and this requires parts, tools, personnel, and a workspace to perform the work.  To limit this, companies should select the simplest solution available, but take care to ensure all required capabilities are still met.

Vehicle Software

Software is the last major attribute of AGVS systems.  Most, if not all, AGVS solutions ship with propriety software that allow users to interact with the system.  Tasks like programming vehicle routes and monitoring vehicle status are accomplished through the software’s interface.  It should be as simple and user friendly as possible. Perhaps most importantly, it must work with other warehouse systems.  For instance, if the AGVS program cannot interface with your warehouse management system or enterprise resource program, it will be very difficult (perhaps impossible) to use because orders to move items from one point to another cannot be communicated to the AGVS.

Employee Interaction

Finally, remember to consider people.  As previously mentioned, employees will have to maintain the AGVS, control/program it via software, and interact with it as they perform material handling operations.  Ease of training is important: the faster people learn how to use the AGVS, the faster it starts generating a positive financial impact on the bottom line.  Safety is also critical.  Without strict safety features and material handling processes, AGVS vehicles have the potential to seriously injure employees.

Making the Selection

Selecting an AGVS can be daunting.  There are many variables to consider, from vehicle navigation to system training, all of which will affect operations in a variety of ways.  Fortunately, there is a way to narrow down the choices to a single system that makes sense for your specific application.

1. Select the right vehicle for your product - First, one must understand that automated warehouse vehicles are really a system consisting of many components. Then, it is possible to start specifying these components, beginning with the material to be moved: it is critical to ensure the AGVS vehicle can transport it.
2. Develop a requirements document and support plan - Next, one should generate requirements for a support structure that meets the footprint, energy needs, and storage requirements of the facility; followed by specifying the software requirements based on needed interfaces with existing software systems and ease of use by employees.
3. Integration - Finally, companies must ensure that the AGVS is as easy to learn and as safe as possible.

At Bastian Solutions, we have been helping clients navigate the AGVS selection process for years.  We have experience in nearly every industry, from manufacturing to health care, so we have the expertise to reduce the large universe of AGVS options down to the one that works for you.  If you are in the market for automated warehouse vehicles, contact us today!  

Author: Adam Cole