Whether it’s in the warehouse or in the storage feed area – the future belongs to modular, autonomous agents. At least that what industry publications and research centres predict. It seems we’re witnessing the beginning of the end of conventional conveyor technology.
But what is a modular, autonomous agent? In the field of distribution logistics, this term stands for a vehicle with its own intelligent control. This distinguishes it from passively driven load units on conventional conveyor systems and also requires a control system able to handle complex and abstract tasks. So instead of “Go to x-position 657” the system could ask for complete, autonomous handling of a task such as “Remove the good from shelve 4711 and carry it to transfer location 0815”.
At this point, we have to dispel a widespread myth. Even a comparatively ‘dumb’ vehicle is able to behave like an agent. This means that the intelligence doesn’t necessarily have to sit on the vehicle physically. In the end, it’s irrelevant whether the CPU for the agent’s software is attached to the vehicle or to a central computer, which processes the commands and guides the vehicles remotely. In many cases, the common use of a central computer by several agents is a more economic and better solution.
Advantages of a modular facility design
This leads us to another important aspect: modularity, which is designing a facility using compatible modules. That’s basically what it’s all about. The vehicles’ autonomy and intelligence are nothing but technology components to archive the goal of modularity.
Why is this so important? A system comprising modular elements promises less complexity and shorter construction and implementation periods. Also, these advantages should become noticeable by improving flexibility in day-to-day operation. Something that can be assembled like Lego bricks will surely by adjustable to changed requirements without too much hassle.
The good news first: most of the time, this is true. Modularity leads to more flexibility and faster implementation of a facility. Because the individual elements are either not physically connected at all or they are using a standardized interface (like the knops on Lego bricks) and may be combined in different ways. The same holds true for the connection of modules on the control level. This not only increases flexibility, it also reduces the amount of planning necessary to adjust the individual connections between elements of the facility.
Like busses and cars
So where’s the catch? The required technology is available and largely mature. Why is there no general switch towards modular, autonomous agents for conveying and storage, or at least a combination of both systems?
Even the new, cost-effective technology does not change one fact: flexibility and modularity come with a price. And in many cases, this price is simply too high.
Just like a bus trip is cheaper per person than a car trip (as long as there are enough travel companions going in the same direction), modular conveyor technology with autonomous agents does not measure up to conventional conveyor systems in terms of cost/performance ratio. Contrariwise, when there are not enough passengers with the same destination, then cars are much cheaper than busses. Consider for example the connection from the goods-in section to the high bay warehouse. Because all goods take the same way, a conventional conveyor system will always be cheaper than a large number of autonomous vehicles.
Only when routes tend to change often or handle throughput infrequently, an autonomous vehicle might be the more economical solution. The same is true for autonomous vehicles entering the warehouse or even carrying the warehouse around (so to speak). With increasing throughput, not only will the organization of a large number of agents and the coordination among them become ever more complex, but the costs will simply take off. The higher the throughput, the more attractive are conventional designs.
But what modular, autonomous agents will never lose is the advantage of greater flexibility. In the end, you have to calculate: how much are you willing to pay for flexibility?
However, this doesn’t necessarily have to be an either-or-decision. Hybrid facility designs allow you to combine both worlds. And we still haven’t reached the end of the line with regards to modular concepts in conventional conveyor systems and storage devices. I am confident that we will see a number of interesting developments in the future.