Decision Point on Power and Free Conveyor

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Chao Gao asked Jan 19 2017 at 12:47 AM Phil BoBo edited Jan 19 2017 at 2:09 AM

Decision Point on Power and Free Conveyor

In the attached model, there are two decision points, when an item comes to DP2, it will stop and wait until the first available dog pass over DP1 in the horizontal conveyor, then it will release the item to down stream conveyor, the ideal is to ensure when the item comes to the mainline conveyor, there won't be any wait time.

Is there a way to have the decision point sensor the dog passing it and check the content of the dog? Or some workaround that does the same function?

pf-updated.fsm

Thanks,

Chao

Software Version:

FlexSim 16.2.2

power and free conveyor

pf-conveyor.png (35.6 KiB)

pf-updated.fsm (24.0 KiB)

Answer 1 · 2017-01-19T01:05:49Z

Phil BoBo answered Jan 19 2017 at 1:05 AM Phil BoBo edited Jan 19 2017 at 2:09 AM

Attached is an example of how you could do this using a Photoeye with a Clear Time instead of a Decision Point, and adding a List to synchronize the items and the openings at the photoeye.

This is just a starting point. You may need to customize the example more to fit your exact situation.

4766-pf-updated-photoeye-and-list.fsm

photoeye-and-list.gif (1.0 MiB)

4766-pf-updated-photoeye-and-list.fsm (28.2 KiB)

· 2

Chao Gao commented · Jan 19 2017 at 1:32 AM

Thanks for the super helpful tip!

Is there a way to make the clear time a dynamic value based on the size of the item that just passed? reality is different size of packages will be traveling on the conveyor and depends on the size, the clear time also need to be different.

0 ·

Phil BoBo ♦♦ Chao Gao commented · Jan 19 2017 at 1:58 AM

The previous model didn't work correctly if you had multiple empty dogs in a row.

Attached is a new model with a slightly modified process flow to sort that out.

This one simply has a delay/decide loop that happens every second to simulate a trigger that matches up with the speed of the dogs passing. If you change your conveyor's speed or dog spacing, you'll need to adjust the delay time accordingly.

This one should work fine with objects of different sizes, as the clear time of the photoeye is no longer used (although it is still checking to see whether the photoeye's state is blocked).

This logic more closely matches what you asked originally than my previous example does.

2 ·

4766-pf-updated-photoeye-and-list2.fsm (30.2 KiB)

photoeye-and-list2.gif (1.8 MiB)

photoeye-and-list3.gif (1.8 MiB)

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