topic Re: Problem stacking pallets in Rack in FlexSim Forum

Problem stacking pallets in Rack

SebastianCanasV — Tue, 18 Oct 2022 22:55:34 GMT

[ FlexSim 22.0.8 ]

Hi all,

If I store boxes in a rack, it will fit properly considering x-y-z dimensions:

When I use Totes, it will do as well as with boxes:

This is not the case if I use pallets, it seems that the Rack is only considering the z height of the pallet and not the whole z height considering the products packed within it:

Is this a bug?

Stacking_Pallets.fsm

Re: Problem stacking pallets in Rack

jason_lightfoot_adsk — Tue, 18 Oct 2022 23:45:37 GMT

The stacking doesn't consider the content of the item being stored - so totes only appear to stack correctly - if the contents exceed the tote dimensions that is not considered - it just uses the tote bounding box. It not a bug, it's more of an over-simplification which needs rectifying.

Attached is a model with a new pallet in the flow item bin that uses the simple packing method to stack inside, like the tote, and additionally changes the pallet bounding box size when you pack/unpack items (using the pallet's OnReceive and OnSend behaviors), while preserving the pallet visual.

stacking-pallets_jl.fsm

Here's a library containing the pallet for easy loading into your model.

AutoSizingPallet.fsl

Here's an example of pallets being packed,stored, unpacked and re-stored in a rack based on the available space:

PalletSpaceExample.fsm

Re: Problem stacking pallets in Rack

joerg_vogel_HsH — Wed, 19 Oct 2022 07:28:50 GMT

@Sebastián Cañas , please highlight a container item. You will notice, that a pallet is framed in its outer limits just like a tote. But a tote stores items inside and a pallet outside of this frame. If you stack such objects then stacking Methode evaluates just the dimension of those yellow frames.

Re: Problem stacking pallets in Rack

SebastianCanasV — Wed, 19 Oct 2022 13:43:25 GMT

Thanks @Jason Lightfoot for the explanation!

Re: Problem stacking pallets in Rack

joerg_vogel_HsH — Fri, 20 Jan 2023 16:24:52 GMT

I discussed a dynamic pallet before, unfortunately such pallets behave a bit strange, if they are inside of a queue and their content changes or their height differ.

Re: Problem stacking pallets in Rack

jason_lightfoot_adsk — Fri, 20 Jan 2023 16:34:23 GMT

I think that issue is one of restacking without removing pallets - I don't think there are many examples where people take from a bottom pallet without removing the upper pallets.

Note this method doesn't use drawsurrogates or dummy objects - the pallet and item tree is exactly as you'd expect and can be virtualised and restored as any normal pallet.