Despite their importance, successful implementation of warehouse management systems (WMS) is seldom fully realized in highly automated distribution centers.  This is evident in the many WMS implementations of new and upgraded distribution centers that are not adequately functional or fully utilized by staff—in some cases even years after they were targeted to be completed.  It is also evident in the excessive cost overruns caused by WMS projects that were not properly planned or executed.

Today, simply installing material handling equipment is not enough.  A more holistic perspective is required for starting up successfully operating distribution centers.  Without a fully functional WMS operating at 100 percent at go-live or shortly thereafter, the greenfield or upgraded DC will fail to perform at expected levels of throughput and efficiency, and the anticipated ROI will be unrealized, or delayed at best.

Warehouse Management System Goals

The objective of the WMS is to provide a set of computerized procedures to manage the movement of inventory and orders within the warehouse, and enable a seamless link to order processing, logistics management and material handling equipment (MHE) systems within the facility.  These MHE systems handle receiving, put-a-way, storage, picking, packing, labeling, sortation, shipping and returns.  External to the warehouse, the WMS links to freight carriers for incoming deliveries and outgoing order delivery confirmation.

Highly automated distribution centers may have many material handling equipment components and sub-systems, each with their own discrete control systems such as warehouse control systems (WCS) and programmable logic controllers (PLCs), which require integration with the warehouse management system into a single-source point of control.

Additionally, WCS, traditionally functioning as middleware real-time interfaces between the WMS and PLCs that control the material handling equipment, are now taking on more functionality and looking more like a WMS, effectively blurring the lines between conventional WCS and WMS applications.  Such WMS functions like managing order activity and batching orders for waving can now be accessed through a WCS, allowing distribution executives another option to fine-tune their DCs while optimizing their investment in software.

Depending on the degree of MHE automation in use within the warehouse, an arsenal of automatic identification and data capture (AIDC) technology can be employed, such as barcode scanners, mobile computers, wireless LANs, magnetic stripes, optical character recognition (OCR) and radio-frequency identification (RFID) to efficiently monitor the flow of goods.  These units capture and relay data throughout the distribution system in real-time via wireless transmission to the WMS, which then can make available comprehensive and detailed reports about the status of inventory and orders moving through the warehouse.

WMSs process huge volumes of data on a split-second, real-time basis with near flawless accuracy, while integrating with ERP, shippers, hundreds of AIDC units, and dozens of MHE systems operating thousands of I/O.

Clearly, the WMS is the most critical component of a warehouse's operation.