question

In your model, you have two general process flows, one for each operator with duplicated activities. Your flows are being run by the orders coming into the warehouse. This creates a more complicated problem when trying to have the operator pick up all items from the list at once. Let me propose a new way of thinking about it. I’ve worked on a few picking models like this and it also seemed to work best by having orders come in to the model represented by a token. That token then creates a list of picks each represented by a token. The pickers are also represented by a token and that token moves through the logic of how the operator decides what order they’ll pick and goes through each pick in the order.

Instead of looking from the perspective of the items or orders, you can have the operators 'thinking' for themselves by looking for work when they are available (pulling from a list). Once they have the list of items to pull, then they go through each one, pick the item, move to the next, until they've picked all items. Then they drop them off at the queue.

Additionally, you can create an instanced process flow that attaches to each operator so that you don't have to duplicate activities for each operator. For more information about instanced flows see the user manual: https://docs.flexsim.com/en/20.0/ModelLogic/AdditionalConcepts/ProcessFlowInstances/

I’ve made those updates to your model. I kept your data management the same, although it could be a little more streamlined with all of the different referencing. The model may seem more complicated, but you’ll find it’s far more flexible. You can more easily make adjustments to how decisions are made as well as collecting statistics (for instance, how long does it take to pick an order, or complete each pick).

On a side note, if you use the AStar Navigator, you can set all of the racks as members of the AStar and keep the operators from walking through the racks.

load-item-changed.fsm