While strategic and tactical planning are proactive by nature, operational planning is proactive and reactive.
A shift plan amends the roster with workstation or area information: Which warehouse operative will work at which workstation (or in which area) in which shift? This is the proactive planning step. The period we look ahead into the future depends highly on the kind of business. We might assign people to workstations just for a week, or we might assign people to future peak seasons. Let's say that from the capacity plan, we know the required capacity for Black Friday, and therefore we assign people to shifts and workstations specifically for this week.
The following shift plan is on a "week" granularity. It is just an example for a few warehouse operatives and just for one month.
We could break down the weekly granularity, but that's simple, and we leave that to the reader's imagination.
Weekly & Intraday Balancing
Even if we plan proactively, we know that the warehouse remains VUCA. The best plan cannot prevent numerous reactive changes throughout the weekly and daily operations. To keep VUCA in check, we need to
- coordinate the incoming goods very well: We need to know exactly which day and when a truck arrives.
The delivery information in ERP systems is usually not exact; it is just an indication of incoming goods.
That's why we need a really good and integrated goods-receipt-planning. As soon as delivery dates change, we potentially must react and change the roster and shift plan for the affected week.
- predict the expected load per hour and workstation, e.g., "at 10:00, we will need 25 people at picking."
- adjust the predictions based on changing conditions (a customer places 10,000 additional orders, five trucks are late, ...)
- rotate people between workstations quickly in case of changes.
- handle technical downtimes, find workarounds and rotate people quickly, either to avoid under-utilization or to cope with more work.
- have experienced people whom we can flexibly assign to various tasks and workstations.
Often, intraday balancing is highly complex. One needs to balance (changing) orders, incoming haulers (early or late), sick leaves, technical downtimes, and more. The operational flow and efficiency depend on the knowledge and experience of the operational people. They know exactly how to handle fluctuations and exceptions. They sometimes know by watching the material flow or by listening to the sound of the plant that something is wrong and that they have to react.