The choice of system follows your item structure and access frequency – not the floor space available. For small parts with high access density and limited footprint, a cube storage or shuttle system is usually the most economical option. With a few thousand items and moderate access rates, vertical lift modules are sufficient. For pallets, high-bay racking with a stacker crane remains the benchmark. Ultimately, however, project success depends less on the mechanics than on the integration: without a clean interface between the automated storage system and the warehouse management system, the promised throughput stays unused.
The system types compared
All throughput figures are guide values per machine or per installation and depend heavily on item range, order structure and the number of picking stations.
| System | Suitable for | Guide value throughput | Limitations |
|---|---|---|---|
| Vertical lift module | A few thousand small-parts items, moderate access rates, room height to be used | approx. 30–120 accesses/h per unit | Scales only by adding units; sequencing barely possible |
| Cube storage (bin grid) | Large small-parts item count, high access density, low ceiling height | approx. 200–600 bins/h per installation | Not suitable for bulky or heavy goods; ceiling height caps capacity |
| Bin shuttle system | High throughput, order sequencing, broad item range | approx. 500–1,500 bins/h per installation | Higher investment; fixed aisle layout; building geometry must fit |
| Automated small parts warehouse with stacker crane | Medium throughput, high storage density for small parts, long-term stock | approx. 80–150 dual cycles/h per unit | One machine per aisle – a failure affects the entire aisle |
| Pallet high-bay racking with stacker crane | Pallets, full-pallet picking, goods-receipt buffering | approx. 25–40 dual cycles/h per unit | Building height, permits and fire protection are project-critical |
| AGV / AMR | Flexible transport between existing zones without structural changes | Depends on fleet size | Creates no storage density – does not replace a storage system |
Five steps to a sound decision
- Analyse item and order structure. Accesses per item over twelve months, ABC distribution, lines per order, bin and weight classes. Without this data, any system recommendation is guesswork.
- Calculate for the peak, not the average. What matters is the peak hour of the peak day, not the annual mean. A peak factor of 2 doubles the required system throughput.
- Check the structural constraints. Usable ceiling height, floor load capacity and flatness, column grid, fire protection concept and escape routes. These points rule systems out faster than any business case.
- Define the growth path. Modular, expandable systems cost more initially but avoid a full system replacement if volumes double within three years.
- Settle the integration before the mechanics. Decide which system owns the storage strategy – your WMS or the machine manufacturer’s controller. That decision shapes processes and follow-up costs more than the choice of hardware.
Why integration decides the outcome
An automated storage system only delivers the throughput stated in the specification if orders arrive in the right sequence and at the right pace. That is precisely the job of the material flow control layer between the warehouse management system and the machine technology. At proLogistik Group, the pLG Automation module fills this role: it connects conventional conveyor technology, shuttle systems, automated small parts warehouses and AGVs to pLG WMS and coordinates transport within the installation.
For AutoStore installations, a direct connection is also available via the pLG Autostore Connector. The practical benefit: there is no need for a subordinate sub-WMS to run the installation. Stock, strategies and order control stay in one system instead of being reconciled between two data sets – fewer interfaces and less day-to-day coordination effort.
A second point is often underestimated: whoever connects one system today will typically connect a second one within five years. A vendor-neutral WMS with standardised interfaces keeps that option open. A machine controller that only knows its own hardware does not.
Three mistakes that make automation projects expensive
- Selecting the system before analysing the data. A system sized on gut feeling is either too small for the peak or permanently underused.
- Treating integration as a budget leftover. Interfaces, testing, fallback strategies and emulation are work packages in their own right. Planned too late, they push back the go-live.
- No fallback process. Every automated zone needs a defined manual emergency mode – otherwise a single fault stops all outbound shipping.
Frequently asked questions
Which automated storage system suits a small company warehouse?
With limited floor space and a few thousand small-parts items, vertical lift modules are the cheapest entry point. If access rates rise significantly, cube storage is more economical, because it works from roughly four to five metres of usable height and grows modularly.
At what order volume does an automated storage system pay off?
There is no universal threshold. What matters is picking lines per hour at peak, labour cost per line and the price of floor space. Automation usually becomes attractive where staff are scarce or where extending the floor area would cost more than the installation.
Do I need a new WMS for an automated storage system?
Not necessarily, but the existing system must handle bin management, sequencing and a material flow interface. Pure inventory tracking without order control is not enough for automated zones.
How long does it take to connect an automated storage system to the WMS?
With standardised interfaces, the integration part typically takes from a few weeks to a few months, depending on process depth and testing scope. The effort can be assessed in advance and quoted at a fixed price; bespoke custom interfaces extend the project considerably.
Can I run installations from different manufacturers together?
Yes. A vendor-neutral material flow control layer links different technologies and manufacturers within one process. The prerequisite is a WMS that retains the leading role instead of handing it to a single machine controller.
What happens if the installation fails?
You need a documented emergency mode: manual access to at least the A items, defined priority orders and stock resynchronisation after restart. These processes belong in the specification, not in the commissioning phase.