ATs dont get called by Dispatcher

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ptelleria
Posts: 16
Joined: Wednesday 06 July, 2016 - 13:35

ATs dont get called by Dispatcher

Post by ptelleria »

Hi:
I am modelling a cross docking distribution center, to know how many AGVs would be needed.
I am using the standard Disptacher to call the Advanced Transporters.
However, when the queues are getting full, the Dispatcher is not serving the tasks to free/idle transporters.
When are events created in the dispatcher? I would suppose that:
1-when a product enters the queue
2-when a product leaves the queue (for the next one)
But as you can see (advance till hour 6 or more), the queues keep filling with ATs idle. The model is looking for the first free transporter (FFT), and, interestingly, the ones that are left idle are AGV12, 13, 14, 15 (connected to cannel 12, 13, 14, 15).
If I change the logic in the midel of the run to LFT, then those starte receiving tasks...but the ones left idle are connected to channels 1,2,3 !!!
Thanks
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Pedro
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HarryBunnik
Posts: 362
Joined: Monday 07 February, 2011 - 11:22

Re: ATs dont get called by Dispatcher

Post by HarryBunnik »

Hello Pedro,

Your problem is caused by the principle how tasks are divided over AGV's. What the dispatcher does, is distributing a task from (for instance) Zona3 to an AGV. Then he waits until that product is picked up at Zona3. Once it has left the queue, the dispatcher is informed that the task is finished and a new pick-up task is created and assigned to the next free AGV. This means that per pick-up zone, only one task is running at the same time, since there is only one pick-up point. And due to the travel time an AGV has, this limits the number of AGV';s that are needed. And as a result, the last or first 3 are never "needed".

I've made a small model change, where I've divided the 4 zones in an "a" and a "b", and here you'll see that all AGV's are being used.
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I hope this makes it a bit more clear.

Cheers,

Harry
ptelleria
Posts: 16
Joined: Wednesday 06 July, 2016 - 13:35

Re: ATs dont get called by Dispatcher

Post by ptelleria »

Hi Harry,
Many thanks for the response.
Now I understand how tasks are created/triggered. So the solution is to fraction the incoming queues. It works (perhaps I'll create one more per entry point).
Now I'll try to generate a custom dispatcher, to dispatch orders not to the first free transporter connected, but to the closest free transporter to the triggering queue.
cheers
Pedro
Pedro
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HarryBunnik
Posts: 362
Joined: Monday 07 February, 2011 - 11:22

Re: ATs dont get called by Dispatcher

Post by HarryBunnik »

Ha Pedro,

Good that it works for you :-)

That sounds like a good idea. Perhaps you already have a plan how to do it, but just in case I would like to point to the "Distance Table" that is available under the Network controller. If you check the node where the AGV is currently heading to (2nd out of the AGV) and the place where the pick up is to be made, you can create an easy and fast check.

Good luck!

Harry
ptelleria
Posts: 16
Joined: Wednesday 06 July, 2016 - 13:35

Re: ATs dont get called by Dispatcher

Post by ptelleria »

Thanks Harry for the tip!
Pedro
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