High-Bay Warehouse Control with Simulation

Supporting an intralogistics provider in extending and improving its control software for automated high-bay warehouses: first with Tesium, a purpose-built simulation of the complete warehouse, then with slot allocation, SAP integration and a universal base system.

Period: 2003 – 2004 · Client: provider of intralogistics systems · Industry: logistics

Challenge

The client owns control software for automated high-bay warehouses that is to be extended and improved, but so far could only be tested to a very limited extent. What matters to the warehouse operator: fast storage and retrieval and well-used storage space.

The technical challenges behind it:

• Testability of the control software: Until then, the control software could only be tested to a very limited extent, both on the real warehouse and without it. The Tesium simulation replicates the entire high-bay warehouse and enables reproducible long-term tests, debugging and optimization independently of the real installation. It was the client's top priority.
• Universal base system and project-specific customizations: The control software is to be built as a general-purpose base system for high-bay warehouses that is customized for specific projects. Accumulation conveyors (transport lines for pallets or other load units), for instance, mostly behave the same and are adjusted via parameters such as length and speed; special equipment such as dedicated sensors is added per project.
• Coordination of the conveyor systems: Accumulation conveyors and stacker cranes are addressed via the installation's programmable logic controller (PLC). The software must coordinate their transport orders and react to feedback from the installation.
• Slot allocation and optimization: For every storage operation, a suitable free slot must be found. At the same time, the overall occupancy of the warehouse should remain favorable. The simulation makes it possible to compare and optimize different algorithms for material flow and slot allocation.
• Integration with SAP: The control software is connected to SAP so that warehouse management and material flow work with the same data.

Role and Implementation

Software Architect, Backend Developer, Test Automation Engineer
2003 – 2004 · Extension and improvement of the control software

Step 1 · Simulation of a high-bay warehouse

• Architecture and implementation of Tesium, a simulation platform developed specifically for this project that models a complete high-bay warehouse with all functions relevant to the control software
• Modeling of the components of a high-bay warehouse: accumulation conveyors, pick-up points (entry points for load units), stacker cranes and PLC feedback
• Parameterizable behavior (e.g. length and speed of the accumulation conveyors), extensible with project-specific features such as additional sensors
• Completed and used for reproducible long-term tests, debugging and optimization, e.g. to compare different algorithms for material flow and slot allocation

Step 2 · Control software: base system and project customizations

• Algorithms for slot allocation, material flow and warehouse optimization
• Integration with SAP
• Alignment of the control software with a universal base system for high-bay warehouses
• Project-specific customizations of the control software for specific high-bay warehouses

Technologies

• C++
• Microsoft SQL Server
• Siemens SPS
• Tesium
• SAP