Let’s start with the contradicting terms of automation and flexibility. As a warehouse management professional you would often equal automation with a complex MHE system (Materials Handling Enterprise Systems) including conveyors, sorters, high-bay storage cranes etc. Most of us looking for such solutions think of it as a black box, a closed system supplied by an automation vendor to meet strictly defined input/output requirements.
A ONE SYSTEM approach for automation works fine when you operate in a stable environment. That means not too much change in product assortment, order patterns or distribution channels or when you can afford the luxury of significantly over-dimensioning your system and facility. Under such conditions you can go ahead and create a business case based on the key factors of volumes (peak and average), utilization (the system must at least be in use x hours on average), and labor cost level.
The last couple of years have clearly put our ability to change and adapt into focus. It is therefore wise to adopt this broader definition: Automation is any measure you implement to make your operation perform smarter and produce more with less people. It means getting access to and making use of the right information to eliminate unnecessary and/or manual process steps. Adding MHE systems is one option, but there are certainly others. The key consideration is how FLEXIBLE you want to be in coping with changing conditions. It requires a design where automation can be included to improve specific tasks or sub-processes, allowing you to expand and automate entire parts of the operation.
One key principle is that you should NOT build your operational processes around your automated MHE systems, but instead take a PROCESS APPROACH and look at the automated processes as a way to address certain parts of the operation. It is dangerous to have a portion of the solution mandating/limiting the overall solution. In a warehouse context we need the support of a warehouse management system that can tie in larger and smaller MHE components when needed, and to coordinate that with mobile scanners and voice users and even manual processing. And – maybe most importantly – make them interchangeable!
The characteristics of the WMS have a key impact for the process approach. A proper WMS, designed for high productivity, automates the operation by creating tasks which are automatically pushed to workers and automation sub-systems whenever there is something to do. It minimizes idle time and gives the worker a clear picture of what to do, which calls for fewer manual operations and reduced worker expertise. A best-of-breed WMS drives the operation and gives supervisors and managers a real time overview of labor and capacity across manual and automated processes.
A key requirement is to enable a seamless interaction between your WMS and the WCS controlling the automated equipment. Clear separation of responsibilities is essential, and some principles to a sound approach are expressed in this table:
WAREHOUSE MANAGEMENT SYSTEM
- Manages the overarching order fulfillment activities and breaks orders down into tasks to be performed.
- Passes tasks to the WCS and receives progress updates and confirmations.
- Predicts and calculates the movement patterns of any manual task, and also estimates time-to-completion for automated processes.
- Tracks task confirmations and progress.
WAREHOUSE CONTROL SYSTEM
- Controls and optimizes its subsystem (conveyor, sorter, picking machine, or a more complete storage and retrieval system like a mini load or pallet racking with cranes).
- Executes tasks per instruction from WMS.
- Performs slotting activities to reorganize and optimize product placement when equipment is idling.
- Owns the definitions of equipment and locations used in the subsystem it controls, making it a “black box” from the WMS perspective.
This means each process needs to be defined with requests and expected responses (confirmed moves, pallet now available in pick-up location, etc.), and you need to ensure that your WMS can be configured to dispatch the right task messages and receive matching confirmation messages.