Problem with Adv. Transporter model

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SouthernForce
Posts: 7
Joined: Wednesday 23 November, 2016 - 17:24

Problem with Adv. Transporter model

Post by SouthernForce »

Dear Community,

For a school assignment I need to build the following case:

At the expedition departement of the factory, finished goods come off a conveyor, whereafter a forklift transports them to the storage area.
From the storage area an other forklift transports the products into trucks which are heading towards the customer.
The factory produces 2 products, Product A & Product B

Product A is made on assembly line 1 & 2, is already packed into boxes and ready to be transprted straight to the storage area. The arrival-time of Product A is NegExp(200). For the two lines together, a maximum of 4 product can be waiting until the lines get overflown. The forklift can transport 2 units of Product A at the same time. The pick and place with the forklift takes 10 seconds.

Product B is made on assembly line 3. At the end of this line, the products are placed into wooden crates (containers), which takes no additional time. One crate can fit One product B. The arrival time of Product B is NegExp(150). Same restriction as Product A, only 4 products can be waiting until the line overflows/shuts down. Next to that, there should always be enough crates in storage at the end of the line to pack the Products, but is restricted to a max of 10 crates. These crates come from the crate-storage. This storage holds more then enough crates. Each forklift can only transport 1 crate a time. Same as with Product A, the pick and the place with the forklift takes 10 seconds.

From the storage-area the products area loaded into trucks. This storage-area has unlimited space. Each truck can carry 50 boxes of Product A OR 30 crates of Product B, mixing the products is not allowed. On average 3 trucks arrive per 8 hours. The distance between the storage-area and the trucks is 10 meters en a forklift transports the products to the trucks.

Each forklift has a speed of 20km/h and an acceleration of 6m/s


There is a fixed path between the lines and the storage area, this path is already created in the model.

Now,I have the following problems:
-First, we use the student edition of ED, so I'm limited to a max of 30 atoms (thats why my upload doesn't contain a network controller)
-Second, my forklifts don't travel via the paths but randomly across the model....
-Third, my model so far contains everything untill the storage area. I still have to build the part where the trucks get loaded but I don't know how, because of the 30 atom limit.

Is there anyone here that can give me some advise on how to build this?
As far as I can see, the labels I've put on the models work as they should and the forklift transports them to the correct destination (Product A directly to storage-area, crates to assembler, assebled product B to storage-area).

Kind regards,

Mitch
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HarryBunnik
Posts: 362
Joined: Monday 07 February, 2011 - 11:22

Re: Problem with Adv. Transporter model

Post by HarryBunnik »

Hello Mitch,

I downloaded your model, added a network controller and optimized the network and it indeed seems to work well. The AT is then also following the network as intended.

As far as your problem goes with the limitations of the student version; I fear that it's not possible to work around that and when I see the description of the model, you will need indeed more then just 30 atoms.

What you could consider is:
  • Using the license that should be available at your university.
Or Kind regards,

Harry
SouthernForce
Posts: 7
Joined: Wednesday 23 November, 2016 - 17:24

Re: Problem with Adv. Transporter model

Post by SouthernForce »

Hello Harry,

Thank you for your quick response!
My university does indeed have the full license, but useally we are intended to do it from home.
It's a relief to know that the model so far is correct, so I can reproduce it at the uni computer.

Still one questions remains though, the fictional trucks behind the storage area..
Visually. the products have different colors, red and blue, so it's easy to track them.
If I set the trigger on exit for Source 1 & 2 to Label([Product A], i) := 1 and on source 3 to Label([Product B], i) := 1.
The atoms should be able to identify the difference in products by their name, but how do I make sure that the "trucks" only get loaded with one type of product?
I was thinking about adding a server with a batch rule, 50->1 and 30->1 but then I need two different servers with a send to statement on the storage area 6. By atom name: if the atom name matches AtomName then send to channel 1 else 2.. This could work but I only receive 3 trucks, per 8 hours and the frequency of the loadtypes is not given... So that would be randomly decided.
Any ideas on how to make sure only the given number of products of a product type is let through to the server and eventually to the sink?
Keep in mind that these products need to be transported with a transporter first :?
SouthernForce
Posts: 7
Joined: Wednesday 23 November, 2016 - 17:24

Re: Problem with Adv. Transporter model

Post by SouthernForce »

I couldn't find the "Edit" for my previous post :?
But I have an additional question, I'm trying to get the forklift, which is in the above stated problem, to pick 2 units if it is product A and 1 if it is Product B and then repeat it 25 times for Product A or 30 times for product B. But I cant seem to get the 4DS Script working... I've tried it with the Label{Product A] statement, even with the colors blue and red which belong to the items but also no luck
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HarryBunnik
Posts: 362
Joined: Monday 07 February, 2011 - 11:22

Re: Problem with Adv. Transporter model

Post by HarryBunnik »

Hello Mitch,

When you place labels on the products, you can use these labels to identify them, so I would not use "AtomName", but identify them by label (either direct or conditional). This is also the faster way (processor time related).

it can be indeed an option to use a server or an assembler to bundle the products. Then you'll need to ensure that this is first triggered when there
are enough products there, otherwise you might be waiting for a long time for the last product to arrive to finalize your truck load (have a look at OpenOutput and CloseOutput and sorting your queue in a smart way). You can use a fork lift truck to transport the products from the storage to the assembler

I remember that on the AT there is the option to specify that all products that will be of the same label value. That might be something to consider. the quantity to pick, you can then link to the label as well. Both can be found on the tab "load" of the AT.

I hope this helps you a bit further.

Cheers,

Harry
SouthernForce
Posts: 7
Joined: Wednesday 23 November, 2016 - 17:24

Re: Problem with Adv. Transporter model

Post by SouthernForce »

Hello Harry,

The AT indeed has the "Same container, same label etc." Function but in order for that to work I need a short 4DS to identify that there can fit 2 Products A or 1 product B on the forklift. I've browsed through this whole forum but I can't seem to find anything slightly the same and none of my fellow students does know it either haha. For the last part I could always use time availablity on both server and forklift i think.

If someone could give me the 4Ds for the forklift load quantity, I should be able te re-write it for the server and the rest
SouthernForce
Posts: 7
Joined: Wednesday 23 November, 2016 - 17:24

Re: Problem with Adv. Transporter model

Post by SouthernForce »

Sooo, I finally managed the AT part.
For the people who have the same problem in the future:
Triggers on Exit set to "Name (i) := [A] & Name (i) := " Then set the load quantity on the AT to "if(CompareText(Name(i), [A]), 2, 1)"
Now the AT picks 2 products A from the queue or 1 product B from the other queue.

Now I can look into the storage area. This can't be a queue atom since this will form a "queue", so I'm thining about a ground storage so the possibility to get 50 of A or 30 of B is created. At least I think thats the way it should be created.

If not, I'll be back here :lol:
SouthernForce
Posts: 7
Joined: Wednesday 23 November, 2016 - 17:24

Re: Problem with Adv. Transporter model

Post by SouthernForce »

So, the first part of the model runs smooth.
I put in a script to prevent the forklift from getting stuck waiting at Line 1/2 until there are 2 products A.
So now the forklift just exports crated-products B and crates until the output signal for Product A is released and 2 products are waiting, which is nice :D

So, regarding the case, I'm here:
From the storage-area the products area loaded into trucks. This storage-area has unlimited space. Each truck can carry 50 boxes of Product A OR 30 crates of Product B, mixing the products is not allowed. On average 3 trucks arrive per 8 hours. The distance between the storage-area and the trucks is 10 meters en a forklift transports the products to the trucks.
Everything before this is scripted and works fine.

Now I have to choose between Ground Storage and Queue for the Storage Area.
The case tells me that one truck can be loaded with 50 A or 30 B but not the frequency of the specific loads.
Every 8 hours, on average 3 trucks come along, so every 2h and 40 minutes a "truck" comes along.
I've tried some configurations with a server and time-control, ground storage and queue, but I keep ending up getting infinite mixed products.

I think that I need to add a script that does the following:
-Only activate the AT when a "truck" has arrived
-Let the AT determine what the first product is he loads, is it A then he needs to pick-up 2 units and do this 25 times, if B, pick-up 1 unit and repeat 30 times.
-When finished with the "batch" return to the idle-state until a new truck rolls in.

For the truck part I was thinking to let a source release a container every 2h40m to an assembler, but then I can't put in 4DS since the b.o.m. works with a tabel. Also I would need to fix the measurements of the products and the truck to fit everything. So a server with a double Batch rule would be easier, I guess, but then I have to put in Time-control, not specified by hour but just a infinite 2h40m loop. In theory that should work but I also have loading time, since the forklift needs to drive 10m, at 20m/s, between the storage area and the truck...

I really think that there is an easy solution for this, but I just can't seem to get it.
I would love to upload the model so far, but I only have it drawn on paper because of the 30 atom thingy. Maybe I should get the Pro version... :lol:
SouthernForce
Posts: 7
Joined: Wednesday 23 November, 2016 - 17:24

Re: Problem with Adv. Transporter model

Post by SouthernForce »

Hello there.
Sorry I'm posting so much, but I'm working on this model like 5-8h a day just to figure out how to make it work. So there's a constant flow of improvement.

I fixed the truck arrival with an arrival list which contains the trucks, specified what each truck wants to load and matched the assembler b.o.m. to it. Now, when I attach 2 queue's, one for each product to the assembler, everything works fine, however I need to get a forklift between that....

I'm also not supposed to use 2 queue's as a storage area but thats something for later, I'll come up with something. Maybe a ground storage where the products are seperated from eachother are something. If I could just manage to get the adv transporter to pick the right product, it will all be a lot easier. Reason why it works when queues are directly linked to assembler is because the assembler closes the inputs it doesn't want so only 1 queue let's products flow.
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