question

Adil M avatar image
0 Likes"
Adil M asked Jason Lightfoot edited

Building a conveyor with carriers

Hi,

I would like to build a conveyor with a carrier similar to the model I've attached which I found on one of the answers forum. But I don't see that type of conveyor available in the default conveyors library in Flexsim. I tried mimicking the conveyor settings in my model but could not get packages to be on a carrier as in the model I've attached. Would I need to download any additional library for this or would it be possible for me to get a similar result using the default options within the existing library. entryspacefix.fsm

FlexSim 24.0.2
conveyorcarrierscross belt sorter
entryspacefix.fsm (32.7 KiB)
· 1
5 |100000

Up to 12 attachments (including images) can be used with a maximum of 23.8 MiB each and 47.7 MiB total.

Joerg Vogel avatar image Joerg Vogel commented ·
Conveyor types are a deprecated feature. They aren’t existing anymore.

If you load an old model, they show up. That is all.
Carriers are by default container items. You populate a conveyor system with them and then you put and drag items from them while they move continuously on your conveyor.

0 Likes 0 ·

1 Answer

Felix Möhlmann avatar image
0 Likes"
Felix Möhlmann answered Jason Lightfoot edited

The model you attached uses the "Power and Free" mode which you can activate in the conveyor properties. The major difference (as far as I see it) between this system and carrier items, is that carrier items could individually stop and as such accumulate or separate along the length of the conveyor. Whereas, as the name of the option suggests, the power and free mode has fixed intervals.

capture1.pngAs Jörg said, you can use actual items as carriers, but you need to take the resulting warmup period into account, until the conveyor system is saturated.

A relatively easy way to load items onto such carriers is to push them to a list. A carrier arriving at a DP/Station/PE can then pull one or more items off the list.

In the attached model I demonstrate this in two modes. One where the carrier items are in constant motion and one where they wait until they can load an item.

conveyor-carriers-fm.fsm


capture1.png (3.6 KiB)
· 3
5 |100000

Up to 12 attachments (including images) can be used with a maximum of 23.8 MiB each and 47.7 MiB total.

Adil M avatar image Adil M commented ·

Hi Felix,

1. Is it possible for me to populate the carriers onto the conveyor at an instant at model start instead of waiting for the conveyor to be full of carriers one by one( For large conveyor systems it might take long time)? Also, I see we are using a a schedule arrival to place the carriers on the conveyor. However, in conventional MHE systems we generally have information around carrier size and pitch. Is there any functionality on Flexsim for me to use that as input directly instead of deriving what the gap in seconds should be between two carriers based on carrier size and speed of belt.

2. Say I have a package that is too large for one pallet, instead I want to utilize 2 pallets for a single package. How do I alter my model to achieve this?

0 Likes 0 ·
Felix Möhlmann avatar image Felix Möhlmann Adil M commented ·

1) In theory yes, but you'd need an entry transfer on every conveyor object that you move to the correct positions for insertion in code.

A simpler idea would be to start the conveyors at a very high speed, so they fill up quickly, then lower the speed to what it should actually be.

You can use the "Entry Space" setting to set how far items have to be apart when entering the conveyor. So you can create all carrier items at the start of the model and then let the entry transfer place them according to the this setting.

1720764857133.png

2) You'd need a way to block a second carrier from loading an item while the one in front is carrying an oversized item. For example, you could store all carriers in a global variable array and write their indexes in this array in a label. This way you can refer to the next carrier by reading the index of one, incrementing that by one and then reading the entry in the array at that position. Then have a second label that denotes whether the carrier is empty or full. So you can set a carrier to be unavailable by proxy.

0 Likes 0 ·
1720764857133.png (7.7 KiB)
Jason Lightfoot avatar image Jason Lightfoot ♦♦ Felix Möhlmann commented ·

You can use a 'whole length' side entry transfer for the initial carriers and set the location of each one before you move it onto the transfer:

ConveyorCarrierInit.fsm

0 Likes 0 ·