topic Re: Inbound palletizing operation in FlexSim Forum

Inbound palletizing operation

niket_m — Sun, 06 Apr 2025 03:55:32 GMT

[ FlexSim 22.1.4 ]

I am creating a model to simulate the inbound palletizing loop. Here are the requirements

Stack 20-27 cartons on the pallet based on inbound carton label
Once pallet is full, move it away to a different queue

I could not figure out how to make operators unload cartons to the pallet inside the queue by using standard prompts so started using process flow. However, in the process flow, I am trying to leverage the subprocess to do the same action (once carton hits the DP, move it to the corresponding queue by using the nearest operator). I think there is an easier way to do this, and it's been 3-4 years since I have done some development. Can someone help out with this?

Inbound Pallet Loop.fsm

Re: Inbound palletizing operation

moehlmann_fe — Mon, 07 Apr 2025 08:33:17 GMT

Do the items stop on the conveyor? If not, you might be better of staying with the exit transfers and their feature to continuously update the pickup location.

Re: Inbound palletizing operation

niket_m — Mon, 07 Apr 2025 20:13:43 GMT

No, the cartons don't stop. In real process, operator will need to lift the cartons and scan them to make a decision on what pallet does it go to. This is why; I was facing issues in using the exit transfer logic. I tried to leverage the send by case from decision point, but with that, I cannot figure out a logic to tell operator to place the carton on a pallet inside the queue.

Re: Inbound palletizing operation

moehlmann_fe — Tue, 08 Apr 2025 06:25:06 GMT

You could alter the transport task sequence in the On Receive Task Sequence trigger of the operators. First check if it is a transport task sequence (5 tasks total in the order travel, load, break, travel, unload). Then change the unload destination.

In the attached model I also changed the operators' load time to 0 and instead add a delay task to the task sequence after the load. Otherwise the boxes often times move out of range during the load time.

Note that fixed resources like the queue store how many inputs are pending and will stop receiving more items if that number plus their content reaches the maximum capacity. Normally the unload task would 'inform' them that the transport task is now complete. But since we override the destination this has to happen manually. I use the On Unload trigger for this.

inbound-pallet-loop-1.fsm

You could in theory make use of this to have the queue stop receiving items when the pallet is full and only 'complete' the transports once the next pallet is available.

Re: Inbound palletizing operation

niket_m — Tue, 08 Apr 2025 14:26:42 GMT

Thanks @Felix Möhlmann. This makes sense. I think I can leverage the process flow to control the queue behavior. I can have the queue stop receiving when the pallet reaches 27 cartons and wait till that pallet is moved to a new area and queue is empty.