A recent simulation study, conducted with a customized version of the SCDA warehouse simulator tool, compared and evaluated alternate forklift operational tactics and strategies. As reported separately the introduction of a fast vs slow mover storage-zoning concept reduced average forklift cycle time and forklift requirement while increasing throughput. However, fast mover zones are not without risks. A major risk is congestion of warehouse traffic, i.e. congested forklift or AGV flow. A simulation-based analysis was conducted to evaluate the negative impacts from congested traffic.

The results were as follows:

• 2% productivity loss in forklift pool during early and late shift (off-peak)
• 9% productivity loss in forklift pool during peak hours

While these numbers are acceptable in this specific case they can be higher, depending on the warehouse layout, storage concept, and forklift and/or AGV modifications, and relative distribution in storage dwell times and throughput rates.

A simulator, such as e.g. a modified version of the SCDA warehouse simulator, can analyze, visualize, and evaluate warehouse congestion between AGVs, forklifts, and other flexible resources. This allows operators, managers, investors, and engineers to assess risks and benefits associated with warehousing strategies.

The SCDA warehouse SimPy simulator is a simple template. It can be customized to simulate warehouse congestion. It can also be customized to simulate forklift cycling strategies, storage concepts. And more.

If you are interested in learning more about the SCDA warehouse simulation SimPy (Python) template and model, you can find more information here:

• Link: Warehouse zoning SimPy model
• Link: Efficient and simulation-based warehouse zoning
• Link: Forklift simulation improves forklift cycling and utilization

In this specific project a fast mover and slow mover zoning concept was implemented. The main benefit being reduced forklift requirement during peak operational hours.

In this specific project total forklift need and driver pool could be reduced by a significant amount. The expected productivity loss resulting from collisions and warehouse congestion did not outweight the benefits from shorter forklift movement cycles resulting from the new storage zoning concept.

Linnart Felkl

Data scientist focusing on simulation, optimization and modeling in R, SQL, VBA and Python